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General Category => General Discussion => Topic started by: solar blue on December 11, 2016, 11:22:46 PM

Title: charging batteries
Post by: solar blue on December 11, 2016, 11:22:46 PM
     i have 16 230 watt panels and just got lead acid wired in series for 24v questions are should they bubble hard at charging and would it be safe to set batt voltage at 30 volts  using midnite 150 have owned it bout three weeks    info greatly needed  im new to solar

Title: Re: charging batteries
Post by: Westbranch on December 12, 2016, 12:27:10 AM
You need to add all the info on those batteries / panels that you have, , make model etc, etc, etc for a reasoned response, other wise we are just guessing.  ;)
Title: Re: charging batteries
Post by: sigp2101 on December 12, 2016, 11:43:32 AM
Quote from: solar blue on December 12, 2016, 12:43:49 AM
        panels are 230watts at 24volts  canadian  batteries are 2volt 20insx4x6 11plates or sells i guess i bought them at a coal mine battery distribitor his words was charge them at round 30volts  this all new to me hope to go off grid but looks tuff for it seems there is much for me to learn

Every batt manufacturer has its own propositions on how to charge their batteries properly. Please provide batteries specifications if you know them.
Title: Re: charging batteries
Post by: Westbranch on December 12, 2016, 12:23:38 PM
Did they give you any information as to what they use them for? I have never heard of a Coal Mine battery so I googled it and it looks like they are used in mining locomotives etc instead of diesels so no fumes...

Post some pictures...
Title: Re: charging batteries
Post by: Vic on December 12, 2016, 02:28:37 PM
solar blue,

Are these batteries sealed,  or,  do they have easily removable caps on the battery top cover?

You really should either Post the manufacturer and model number of these batteries here,  or contact the manufacturer to get precise charge,  EQ  and Float voltages,  the Temperature Compensation value for charge/EQ voltages.   Information on the Specific Gravity (SG) for a fully-charged battery,  if the batteries are Flooded Lead Acid (FLA) types.   FLAs have caps on each cell that are easily removable.  You should also try to get info on the maximum charge current that the batteries will accept.

If the manufacturer has charge information for charging  the batteries from PV and a solar Charge Controller (CC),  this would be best,  as charging batteries from Grid power,  can be quite a lot different than is charging from Solar.

If you plan to use all of your PV modules to charge these batteries,   the charge current (charge rate) may be excessive for the batteries,  depending on the battery type,  and specs.   And,  you would probably need more than one CC to use all of those PVs on a 24 V battery.

FWIW,   Vic
Title: Re: charging batteries
Post by: Vic on December 12, 2016, 07:00:37 PM
Hi solar blue,

GNB Exide Titan batteries appear to be in the class of Flooded Forklift batteries.

Were the batteries that you have previously used?

Will continue to poke around on the internet.  looking for data.

The people that sold the batteries to you sure will be a good start in getting the important information on those charging details.

EDIT:  This battery may be similar to yours,  although,  it is in the GNB "Classic" line:

12-85C-11   24   425   9.84   31.5   12.94   23.25    930      M1601208511AFPC
Basic #      volts   Ah   kWh    ... dimensions ......    weight     product model number

FWIW,   Thanks,   Vic
Title: Re: charging batteries
Post by: Westbranch on December 12, 2016, 08:59:23 PM
Since you are making up a 24 volt battery you have to multiply those numbers 2.21 , and 2.6 by 12 as those are the values per 2v cell...

so 26.52V for Absorb and Float and 31.2V for an EQ,
you want to achieve a Specific Gravity of 1.285 and the reference temperature is 70* F

BUT he needs to tell you the Temperature Co- efficient , how much to adjust the charge voltage per degree change from 70*F
Title: Re: charging batteriesk
Post by: dgd on December 13, 2016, 12:05:12 AM
If these are FLA batteries then the float and eq voltages 26.5 and 31.2 look fairly normal but the absorb would/should probably be 29.2v for the 3 hours charge time mentioned or perhaps even closer to the 30v initially mentioned by the coal mining battery seller.
Just IMHO unless these are really designed to absorb at a low 26.5volts
Set the absorb timer for 3 hours and wire those PVs in serial connected pairs (nominal 48v) with 5 parallel strings into the Classic 150 via an MNPV6 with five  15amp breakers, one for each string.
My 2 cents worth  :)

Dgd
Title: Re: charging batteries
Post by: Westbranch on December 13, 2016, 01:30:28 PM
I hope you  are using the Local app that MidNite has available, it will make the settings update task very easy!

The TCV you now have is set in the Local App or MNGP and it is the amount of change that the Classic will make to the voltage it sends to the battery, if temp goes down more voltage is needed, if the temp goes up less voltage is needed.  Once set the Classic automatically adjusts based on the temp received from the BTS (Battery Temperature Sensor).

I believe he is telling you that the Specific Gravity should read 1.300 when you do an EQ but I don't understand why he gave you 2 different values. ??  ???

The MNPV 6 is because you will have 5 STRINGs of panels to combine into one wire to the Classic. example
http://www.midnitesolar.com/pdfs/MNPV12%20BREAKERS%20wiring.pdf

It looks like DGD has chosen the most efficient arrangement for you based on wire costs and simplicity of pulling it all together and most importantly having a high enough Voltage to charge those batteries.
Title: Re: charging batteries
Post by: Vic on December 13, 2016, 02:14:39 PM
Quote from: solar blue on December 13, 2016, 12:52:52 PM
  dgd         i spoke to bat place tcv is like .2 i dont understnd and he says hydro should read 1.300 still dont understand what is the tcv used for  and whymnpv6 and why      and why wire pv to 48v

solar blue,

TCV is Temperature Coefficient Value.  For many Flooded batteries,  like yours,  this setting in the Classic would be in the Charge menu,  under " Temperature Compensation ".  You would want to enter -- 5 mV/C.

The target SG on your Hydrometer is 1,285.   In your phone conversation with the battery person,  you may have mentioned that your batteries were cool or cold,  right now.  In this case  Hydrometer readings would need to be compensated.   For battery temperatures below about 25 C,  the Hydrometer readings are a bit higher than the actual SG of the electrolyte.   This compensation value for SG readings is fairly small,  but,  for cold batteries,  it should be done.

Here is a good article on measuring SGs using a Hydrometer:
http://support.rollsbattery.com/support/solutions/articles/4347-measuring-specific-gravity

The above article gives approximate State Of Charge (SOC),  for batteries that have SGs that are 1.265 when fully-charged,  so your battery will need a slightly different table for that.

The compensation for Hydrometer readings is to subtract from the Hydrometer 3 SG points for every 10 degree F (about 5.5 points per degree C)  for battery temperatures below about 25 C,   and add to the SG readings that amount for temperatures above 25 C (77 F).

This is probably where that 1.300 SG value came from ...   but just guessing.

EDIT:  An Absorb voltage of about 30 V  is probably a fine place to start.  Most Charge Controllers do not have a Bulk voltage setting,  so just set Absorb voltage,  Float voltage,  and EQ voltage.   That stated Float voltage is quite high,  and if your system spends very much time in Float,  the battery will consume quite a lot of water.  You might want to start with a Float voltage  of about 27 volts.

If you do not have your Solar panels set up,  and ready to charge your batteries,  you may want a separate charger that could run from Grid power,  or from a generator.   Batteries with fairly  high SGs like yours,   will discharge themselves when sitting with no loads.

Back to work,   FWIW,   Vic
Title: Re: charging batteries
Post by: Vic on December 15, 2016, 12:56:35 AM
Hi solar blue,

Sorry for the reply delay ...   been traveling.

Regarding battery temperature.   The battery is a large,  heavy item,  and changes temperature fairly slowly.  It will really average the temperature variations that it is exposed to.

AND,  that Battery Temperature Sensor (BTS)  that came with the Classic  will do a good job of automatically changing the charge voltages,  based on the battery temperature that is measures.

For now,  just place that BTS on the top of one cell near the middle of the battery.  Later,  there may be a better place for the BTS.

When a battery is cold,  the charge voltages need to be increased somewhat to make sure that the battery is getting a good charge,  when a battery is warm,  the charge voltages need to be decreased a bit for a good charge.

More later ...  see that you are on-line now,  so will post this.

Thanks,   Vic
Title: Re: charging batteries
Post by: Vic on December 15, 2016, 04:40:38 PM
Hi solar blue,

A new Classic should have a Battery Temperature Sensor included.  This is from the description on the MidNite Solar site:

"FEATURES: •150 operating voltage   ...

   ...   Ships with MidNite Battery Temperature Sensor (MNBTS) and printed Manual".

If the Classic 150 was previously used,  then,  it is not uncommon for the BTS to not be included,  sometimes because the BTS has been installed on a battery,  and perhaps the cable pulled through conduit.

The jack for the BTS is a four conductor telephone type jack,  that is just to the right of the blue terminal block (that is used for the PV and battery cable connections).

The BTS usually has a blue,  flat cable with a blue flat plastic end for the battery,  and a four pin telephone type plug on the other.   The cable is about  4 Meters (approximately 12 - 13 feet) in length.

Here is a link to a photo of the MidNite BTS:
https://www.solar-electric.com/catalogsearch/result/?q=mnbts

More later,   Good Luck.   Vic
Title: Re: charging batteries
Post by: Westbranch on December 15, 2016, 08:20:11 PM
Solar Blue, here is a reference document from C&D that may help you to understand AGM VRLA battery charging.   http://www.cdtechno.com/pdf/ref/41_2128_0212.pdf

and terminology http://www.cdtechno.com/pdf/ref/41_7745_0112.pdf

hth
Title: Re: charging batteries
Post by: Westbranch on December 16, 2016, 02:26:20 PM
If they are so low they started to freeze, inside would be much better.

How low were the SG readings on each cell?

Are both the 12 v chargers the same make /brand?
Title: Re: charging batteries
Post by: Vic on December 16, 2016, 03:16:25 PM
solar blue,

An SG of 1.110  is a DEAD battery.

Freezing of a battery will usually cause so much physical damage that the battery is often ruined,  and not recoverable.

It can be dangerous to try to charge frozen batteries ...   although,  I have no experience doing so.

Keeping batteries in a warmer environment,   for cold climates would be better than having them outside,  even in an insulated cabinet,  box,  or shed.

Yes,  having several PVs in series would probably be fine on a 24 V battery system,  with a Classic 150.

What brand and model number are your solar panels?   This will help us give the best advice.

If you are seeing frozen batteries,   gentle charging would probably be better than charging at a high amp rate.

It may be very difficult to move your battery,   assuming that it is one battery in a metal case,  with batteries connected together with lead bars ...   your battery might have be different,  though.

More later,  Good Luck,   Vic
Title: Re: charging batteries
Post by: solar blue on December 16, 2016, 06:09:20 PM
vic panels are csp 220 canadan batteries werent frozen just bout a 1/8in or just a little better
Title: Re: charging batteries
Post by: Vic on December 16, 2016, 06:56:53 PM
solar blue,  thanks for the added info.

Those PVs  --  CS6P 220,  have a Rated voltage (Vmp) of about 29.3 V,  and a current  (Imp) of about 7.5 A.   SO,  two of these PVs in series for each string would be fine,  connected to the input of the Classic,   strings of three in series would probably be OK.   But,  one would need to know the lowest temperature recorded for your area,  in order to run these numbers to make certain.

The batteries will freeze from the outside,  in.   So,  even a layer on top,  and around the outside,  probably on the upper part of the sides of the case could still damage the plates,  but  go for it in getting these batteries recharged,  assuming that there has been no real damage to the batteries.

Questions;

Are there ANY loads on the batteries?

Are these batteries new,  or previously used?

Have the batteries been sitting,  without being charged for a while?

Were the batteries fully-charged,  when you got them   ... when did you get them?

Do you have Grid power,  or are you using a generator to run the AC chargers?   If you had a way to heat the batteries,  it would help,  as the early charge stages  will not create much battery heating.

Later,   Vic
Title: Re: charging batteries
Post by: solar blue on December 16, 2016, 07:27:39 PM
   hi vic   ive moved battery in took awhile   the batteries arent under load    yes bought in mid nov   they were new at battery place and dont knw if it had been a great while sense charge   ask seller if they fully charged said yes   i do have grid power   building where batteries is being heated as we speak  so out of 16 panels 24 can i paraell to 48 and run safely with out damage to 150
Title: Re: charging batteries
Post by: Westbranch on December 16, 2016, 08:50:56 PM
solar blue you should use the Classic sizing tool at 

http://www.midnitesolar.com/sizingTool/displaySizing.php

I just ran your PV's numbers and you can safely use 3 panels ( in series ) and 4 strings giving 2640W....  using a - 40*C as the lowest temp expected. 

Please do the calculation  again for your own edification and to see the maximum # of panels you can use.

I hope you got as many panels as you need , it appears that they are now discontinued.
Title: Re: charging batteries
Post by: solar blue on December 16, 2016, 10:58:33 PM
   hi westbranch      yea  they are off line trying to recover batteries      why 48v or 72 will that make batteries charge faster be easy to wire the panels either way     would i have to go to 48 or 72 battery or can i still run 24v battery with it      im willing to try anythang
Title: Re: charging batteries
Post by: Vic on December 16, 2016, 11:34:31 PM
solar blue,

The wiring of the PVs into strings of three will have no benefit verses PVs in strings of two.  The Classic will convert the PV input voltage into a voltage that the battery needs,  regardless.

Strings of three of our PVs will be slightly less efficient verses strings of two,  but this is a small difference.

Having MORE PVs weird will help,  by increasing charge current,  within the limits of the Classic output current limits for a 24 V battery.

Do you have that Battery Temp Sensor (BTS)??

If not,  with a cold battery,  once that most of the charge for the battery is done  --  when the  Bulk stage is done,  you may want to manually increase the Absorb voltage.  This is what the BTS would be doing automatically,  if is were connected to your system.

The Bulk stage does about 80 - 85% of the battery charge,  and Absorb does the final charge.

Vic
Title: Re: charging batteries
Post by: Westbranch on December 17, 2016, 12:10:11 AM
Solar  Blue I was not trying to tell you to use strings of 3, and 4 strings.  I just used that as a maximum that appears to be safe... IFF you are going to use a 48Volt battery...

Sorry I left the voltage out in the previous post...

You said

so out of 16 panels 24 can i paraell to 48 and run safely with out damage to 150

I had a hard time trying to decipher what it was that you were really saying..  but you were clear that you did NOT want to damage your classic..  that I tried to answer and gave the link to the Classic Sizing tool..

Please clarify the above quote for us all...

thanks.  :)
Title: Re: charging batteries
Post by: solar blue on December 17, 2016, 12:25:47 AM
  yea westbranch i know   im going to parell to 48with 5 strings going into charger do i have to go to  a 48v battery an inverter i would like to keep 24v battery   im going to parell em gota do something ill listen  and be happy i did im just learning and am so grateful for all the help all yal give guess im brain dead lol  down here in kentucky guess we sometimes are hard to understand we type like we talk im the only one in the south according to insureance man that is doing this thanks again for your help
Title: Re: charging batteries
Post by: Vic on December 17, 2016, 01:00:57 AM
solar blue,

The Classic is an MPPT Charge Controller.  It has the ability to convert a higher panel voltage into the voltage that the battery requires.

So a 60 volt string voltage from two PVs in series will be converted to proper voltage for your 24 V battery.  All that you will need to do is to set voltages into the Classic that match what your battery needs,  based on what the battery manufacturer says are the proper voltages for your battery.

Other types of Charge Controllers  --  PWMs  --  need a PV string voltage  that is much closer to the battery voltage.

CCs like the Classic work magic.   Does this make sense?

Vic
Title: Re: charging batteries
Post by: solar blue on December 17, 2016, 01:18:35 AM
   vic yes that makes good sense  thats what i want a do is make 5 or 6 strings at 48v  now if i can do that and still run 24v battey do i have to put the controler back to  factory settings and  let it quick set or just leave as is hook everythang to it and just put in battery settings  ;D
Title: Re: charging batteries
Post by: Vic on December 17, 2016, 01:22:01 PM
solar blue,

NO,   if you have set the Classic for your 24 V battery,  you will not need to make any change in the settings for any change in string voltage.

AND,  if you were running single PVs previously,    you should find that running two in series will do a better job of charging the batteries.

Again,  if you are not able to use the BTS to adjust the Absorb,  Float and EQ voltages,  then you should do this manually.,   assuming that the batteries are still cool,  or cold.

The Temperature Compensation value for your batteries should be --5 mV,  per 2v Cell,  for every degree C change from about 25 C.    So,  for cool/cold batteries,  the Absorb  (and Float/EQ)  voltages will need to be increased  by 0.06 volts for every degree C that the BATTERY is below 25 degrees C.  The compensation can be a large value for cold batteries.

Later,   Vic
Title: Re: charging batteries
Post by: solar blue on December 17, 2016, 08:19:54 PM
   hi vic     first i thank you and westbranch for your patient  and all the help it took long enough to drill it in my head. let me see if i got  it  take ten panels 24v. series them   to make five strings 48v  to controler. then that should be enough to charge batteries.  i think i spoke with you about frozen battiers. well have warmed them and charging for 24hrs  are now at 1.275  a couple are at 1.300. i am both lucky to say the least and beside myself happy with the out come again many many thanks for helping
Title: Re: charging batteries
Post by: Vic on December 17, 2016, 09:22:46 PM
Hi solar blue,  thanks for the new info.

Very good that you have warmed the batteries,  and that it appears that the SGs have risen to nearly a full-charge.

Do you have the BTS for the Classic ??

Yes,  10 of your 220 PVs arranged as five strings of two PVs should do fine with your 24 V battery,  and the total power from those ten PVs should not exceed about 1600 - 1750 watts ( depending on the outdoor temperature and available sun).   This would yield,  about 50 - 65 amps of charge current into the batteries,   which is a good place for a Classic 150 to be running.

As dgd mentioned previously,   you really should use a Combiner,  with a circuit breaker for each string of PVs,  primarily as a fire safety measure.

If you do not have a MidNite BTS,  you really should try to get one soon,   as this will help your batteries receive a full-charge,  without overcharging them.

What type of Hydrometer are you using?   It is important to have a good quality Hydro,  as you will be basing many decisions,   based upon the readings that the Hydro gives you.

It is a good idea to have a battery Logbook,  where you can log  SG readings,  settings in the Classic for Absorb,  Float and EQ voltages,  absorb time,   EQ duration,   and date,  as well as amount of Distilled Water that was added to the battery bank,  and the date of this topping-up,  etc.

Hope that you will let us know how you are doing.   Good Luck,
Vic
Title: Re: charging batteries
Post by: solar blue on December 17, 2016, 10:00:03 PM
     vic going to order the bts monday   will get the combiner the hyd was given me by battery dealer guess its cheap send type later  we will begin  a log  and yes will give update when done again many thanks to all
Title: Re: charging batteries
Post by: Vic on December 17, 2016, 10:11:25 PM
Hi solar blue,

Looks like you have done quite well in recovering from the situation,  by making some good decisions.

It is nice that the battery dealer gave you the Hydrometer,  many battery dealers do not do this.

The BTS should help your general battery health.

Good Luck,   and please do let us all know how things are going. Thanks,   Vic
Title: Re: charging batteries
Post by: solar blue on December 21, 2016, 01:48:56 PM
    hi vic  well wired panels to 48v  input went from 34v  to 69  best i rember under that watts went to 54 below that is kwh   rite side says 32v i set it at that under that says 1,7v below that says absorb  eq is set 32v  now two questions does charge controler show the amount of charge in battery  the controler is in pv mode  how might L&Q mode help if any  what does it do to help i have bts coming  could i possibly have eq and absorb to hi and does the controler absorb power at nite when resting
Title: Re: charging batteries
Post by: Vic on December 21, 2016, 02:21:38 PM
Hi solar blue,

Are there any loads on this system,  are you using an inverter to power loads,  etc?

Could you post a photo of the main status screen,  when the Classic is in Absorb?

Do you know the approximate battery temperature?

EDIT:  So you have wired the PVs as two in series,  right?   What is the total number of PVs that are weird into the system?

If there are no loads on the system,  then the Current display on the right side of the display is close to the amount of current going into the batteries.  There is an optional accessory for the Classic  --  the WhizBang Jr (WBjr),  this plus a 500 A  50 mV Shunt will show a very accurate measurement of the current going into the battery.

Generally,  the Solar Mode for the Classic will be the best for PV charging of a battery.  Sometimes,  with passing clouds,  Legacy P&O  can be better.

What version of Classic Firmware is the Classic running?   This can be seen by pressing the small round Status button on the display about 7 or 8 times.  It will show the Classic,  MNGP,  and Network Firmware Version numbers ...
Be back in an hour or two.   Thanks,   Vic
Title: Re: charging batteries
Post by: solar blue on December 21, 2016, 05:08:04 PM
   vic   no loads on system   cant do a pic no camera  batteries probly bout 36f  yea rewired panels have five strings 48v  making 69.4 v in  for every degree f   how much do i need to add to Mv
   2054 mngp
   2096   03/26/16 classic
   rev sl4294967295
   if i found the right thing   hope this is right
Title: Re: charging batteries
Post by: Vic on December 21, 2016, 05:51:59 PM
Hi solar blue,

No problem on no photo.

Regarding manually setting the Absorb voltage,  to compensate for the battery temperature,   for every degree C that the battery is below 25 C,  you should add 0.06 volts to the recommended Absorb and Float  (and EQ) voltages.

You should probably take SG readings on each cell of the battery,  and write those down.   This is probably a good time to start a new Battery Logbook.   You would record the date,  SG readings for each cell  --  number each battery and letter each cell of the battery,  unless your battery is like most forklift batteries and all of the cells are in one metal container,  then just number each cell.

You would also want to record the amount of water added,  EQs  and their length,  etc.   All of this info will help  you monitor trends in battery behavior,  note any action that has been taken to try to correct anything that appears to be going amiss.

Since your system has no loads,   you can use the Classic output current  on the lower right of the display,  as a very close reading for the current that is going into the battery.   When this current reaches a value (around 9 Amps  -  about 2% of the 450 Ah battery Capacity IIRC),  begin watching this current closely.  When this current no longer is going down,  this is about the proper Absorb time,  and you could also use it as a good start for setting the Classic's End Amps,  in the Charge>Advanced menu.

EDIT:  Previously  it was suggested that you should probably set your Absorb time to 3 hours.  But  with no loads on the system,  you could reduce this time setting.  You should be able to shorten the Absorb Time,  to about 30 minutes,  or so.

If your system continues with no loads,  then you would probably to not recharge the battery every day.   But,  let's not talk about this now,  and wait until you measure the SG of each cell,   and get more comfortable with your system.


Vic


Title: Re: charging batteries
Post by: solar blue on December 21, 2016, 09:45:50 PM

  Vic

       i have put system back on line 9:35 tonight. Ihave made a log to keep records on batteries
  I have put in it all the things to check and keep up with with.
  you spoke of end amps what might this be and its use?  Thanks for all your help.
 


Title: Re: charging batteries
Post by: Vic on December 21, 2016, 11:51:14 PM
Hello solar blue,

Think that I forgot to mention that your Classic Firmware is up to date,  thanks for checking.

End (or Ending)  Amps is a setting in the Charge menu,  that will allow the Classic to end the Absorb stage,  when the current from the Classic (or the current measured by the WhizBang Jr)  comes down the value that is set for this menu item.

With no loads on the system at all,  the current that the Classic is supplying on its output will only be the current that is going into the battery.

When the current going into the battery (the battery charge current) reaches a fairly low amount,  and this current does not change for a number of minutes,  then the battery can be considered,  fully charged.   The Absorb voltage setting must be in the range of voltages that are suggested by the battery manufacturer,   and must be correctly Temperature Compensated,  for this Ending Amps value to indicate that the battery IS fully charged.

Usually,  this Ending Amps value is in the range of 1 to 2 percent of the 20-hour Capacity of the battery bank.   In the case of your battery,  believe that this Capacity value is 425 Ah.   So 2% of this is about 8.5Amps,  and 1% is about 4.2 Amps.

There is a setting for "  Ending Amps  ",  in the Charge menu  --  go to Charge,  and then scroll over once,  and down once,  to the Advanced menu.   At the left of the Advanced menu,  there is the  Ending Amps selection.  If you press  Enter then the Ending Amps selection is highlighted,  you will be able to enter a value for this.

The benefit of using Ending Amps,  is that  with a battery bank that is discharged by different amounts on every discharge,   the proper amount of Absorb Time need for a full-charge will differ,  compared to  a battery discharged by a different amount.

Finding the proper setting for Ending Amps can require quite a bit of time,   as  SG readings must be monitored to verify that the Ending Amps setting is correct.

With no loads of any kind on your system (not even an Inverter without any loads),  you  could probably only fully charge your battery once per week.   And,  then,  if your batteries are new,  and in good condition,  only for a fairly short time.   You could possibly begin using Ending Amps at a time when your system has a reasonable amount of loads on it.

You appear to have Grid power,  so this system may be intended as a backup power system,  for when the Grid power fails?

More later,   Vic
Title: Re: charging batteries
Post by: solar blue on December 22, 2016, 05:07:46 PM
    Hi Vic
thanks for end amps info I understand that pretty well . The bts should be here friday or tuesday when I plug it in all i need to do is set Mv back to Mv5 then that will adjust chage for temp of battery so after that I need to set end amps correct?
battery sg is staying at 1.275 a little above maybe



                                                                          Many Thanks
                                                                          Solar Blue
Title: Re: charging batteries
Post by: Vic on December 22, 2016, 06:47:59 PM
Hi solar blue,

Yes,  your battery needs a compensation of -- 5 mV/cell/C,  so make sure that this is set.   The Classic will know that there is a BTS installed,  when you plug it in.

Think that you have been manually Compensating for low battery temperatures,  so you may need to adjust the Absorb and Float voltages,  if this has been the case.

YES,  you can set the Ending Amps in the Charge > Advanced menu.  You could start with about 8.5 Amps,  and watch the SGs,  to make sure that you are maintaining good SGs.

Also,  check the Absorb time setting.  The way that Ending Amps works is  that either the End Amp setting,   OR,  the Absorb time setting is what will end Absorb,  so make sure that the Absorb time is set to a fairly long time,  like several hours,  until your system has some loads to discharge the battery.

Your 1.275 SGs are probably fine ...   forgot what the battery dealer or manufacturer says is the SG for a fully-charged battery.

Also,  SG measurements need to be temperature compensated  by a fairly small amount.   SO if your batteries are still fairly cold,  the SG readings will be a bit on the high side,  and could have about 3.5 points subtracted from the readings for every 10 degrees F change from about 77 - 80 degrees F.

There is a Hydrometer  --  the Hudrovolt  --  which compensates for the temperature of the electrolyte of the sample.

Also,  am sure that you know,  that batteries will emit Hydrogen,  an explosive gas,  and some acid vapor when being charged,  and EQed,  so please keep that in mind when you find a permanent place for your battery bank.  Some ventilation with a vent at or near the ceiling of the room where your batteries are located.

With the BTS installed,  the " Temps "  menu will show Battery temperature on the lower left of the display.

There are a few things that should be mentioned,  to help keep your system as safe as it can be,  but later for those,   Vic
Title: Re: charging batteries
Post by: Vic on December 23, 2016, 05:46:27 PM
Hi solar blue,

A couple of comments regarding circuit protection for your system;

You probably know this,  but,  since you have five strings of two 220 watt PVs,  you will need a Combiner,  which has  one DC  circuit breaker for each string of PVs.

Also,  you will need a DC circuit breaker for the input of the Classic,  and,  the most important DC breaker,  is the one on the output of the Classic to protect the cable that connects to the battery.

You may have already done this.  The PV breakers in the Combiner are often sized at the Maximum Fuse rating that is on the label on the back of the PVs,  and in the specification that can be found online.

The Classic's input and output breakers are sized to protect the cable that it is connected to.

FWIW,   Vic
Title: Re: charging batteries
Post by: solar blue on December 24, 2016, 01:30:50 PM
   Hi Vic
           Christmas greeting to You and Family
    Got the combiner bx coming what size breaker should I use for each circuit
     Im using number8awg is that large enough

   
Title: Re: charging batteries
Post by: Westbranch on December 24, 2016, 04:14:58 PM
Thee CB size should be on the back label on the panel,  this link says 15A CB is needed...http://www.solardesigntool.com/components/module-panel-solar/Canadian-Solar-Inc./382/CS6P-220P/specification-data-sheet.html

You will need one per string feeding the combiner.  ;) ;)
Title: Re: charging batteries
Post by: solar blue on December 24, 2016, 07:37:54 PM
  hi westbranch 
thanks for info   hope this is a great holiday season for all thnks again.
If i use 15a for each string of 5  what would be the rite amp size for input to cc and output to batteries and can i place in same bx if possible what is the rite bx for them
Title: Re: charging batteries
Post by: Westbranch on December 25, 2016, 01:41:41 PM
It is possible to put the other CB in the same box but will require you to make some modifications to the combiner that comes with the MNPV6.

As to the CB to the controller what voltage are you settled on?
Title: Re: charging batteries
Post by: Vic on December 25, 2016, 05:20:10 PM
solar blue,   Thanks for the Christmas wishes.   Hope that you are enjoying Christmas,   best wishes to you,  and your family.

It might be time for all of us to slow down a bit.

Previously,  most of the details of your system did not matter so much,  compared with the situation you were in,  in trying to get your batteries recharged,  ASAP.

Now  that this situation appears to have been resolved,  most of us trying to help you will need some more details about what you want your system to do.

For example;
1.  What is the purpose of this system?   Since you have Grid power,  is this a system to back up your grid power?

2.  Is this really for an off-grid cabin,  but you have the grid power elsewhere?

3.  What will be the daily loads on the system,  and when will these loads occur?   You may need to measure the loads with a device,  like the Kill-A-Watt,  for 120 VAC loads.

4.  Do you have plans to add onto this system?

It is the usual approach to design a system,  first,  based upon load on it,  when these occur,  and also what is the maximum load (like a deep well pump,  etc).

Knowing all the info about loads on the system,  the size of the battery,  its voltage,  the size of the PV array,   the size of the inverter,  cable sizes,  etc,   will become much more clear.

Also,  the way the system is laid out could depend upon any upgrade plans.   These things include where the Combiner (for the PVs) is located,  cable sizes,  and the type of box/es that could be chosen now,  instead of needing to tear out things if an upgrade is to be done.

You could do a quick but safe system,  very quickly,  as a temporary setup,  and do a more permanent system later,  but,  things like good quality inverters are fairly expensive,  so,  knowing the system size requirements is important.

Here are a few Links to examples of some of the boxes, breakers,  etc;

Six string Combiner:
https://www.solar-electric.com/mnpv6.html

Small breaker boxes-
Big Baby Box that uses DIN Rail DC breakers:
https://www.solar-electric.com/misobigbabox.html

Four breaker box that uses Panel Mount breakers:
https://www.solar-electric.com/misobigbabox.html

MidNite DC breakers-
Din Rail for the Combiner,  and the Big Baby box:
https://www.solar-electric.com/catalogsearch/result/?q=mnepv&_antispam=antispam_694

Panel mount DC breakers:
https://www.solar-electric.com/catalogsearch/result/?q=mnedc

There are several larger metal boxes that will collect more breakers than the above two boxes,  have space for the large inverter breaker etc.  The largest of these are in a group called e-panels,  which will usually allow the Charge Controller and inverter to be mounted to this panel,  and contain all,  or almost all of the wiring ...  will post those later.

Vic
Title: Re: charging batteries
Post by: Vic on December 25, 2016, 10:27:04 PM
solar blue,

Here are a few of the larger metal boxes that can collect many of the needed breakers and associated wiring in one place,  for convenience and safety.

The MidNite MiniDC is the smallest,  and least expensive of these boxes that are larger than the Big Baby Box,  and the DC Quad box:
https://www.solar-electric.com/midcdipocepl.html

Then,  there are the larger boxes that  have more room for breakers,  and for mounting the CC,  inverter,  etc:
https://www.solar-electric.com/catalogsearch/result/?q=e-panels

I do realize that choosing from this wide array of alternatives may well difficult for you,  as it is difficult to know what is really necessary for your system,  and which capabilities  might never be needed.

However,  for those of us who are trying to help you with your system,  it is also difficult to know just what you want and expect from your battery-based system.   So,  the above is some information on some products that will help collect most of the pieces in one place,  use breakers and other hardware that is designed to work safely and well while working reliably for many years.

The first series in this Post,  the Mini DC boxes are for small systems,  that need few breakers,  and not much space for mounting the power producing hardware.   The e-panels are for larger systems.

But,  these boxes are designed to do the job,  meet Codes,  and be safe,  when used appropriately.

All of the Links are to the Northern Arizona Wind & Sun store.  I have no affiliation with them,  but they are honest,  knowledgeable,  have very good pricing,  will deal with individuals,  ship quickly - usually from stock.   Have used them a number of times,  and  will do again ...   FWIW.

Am not in the business of trying to sell anything to anyone,  but just my quick attempt of a summary of some parts that will help construct a system that uses quality components,  has good documentation,  and is reasonably priced.

Vic
Title: Re: charging batteries
Post by: solar blue on December 26, 2016, 02:01:08 PM
       Hi Vic
   In answer to last want to run the 120v system in house
I do have grid trying to supplement home or even make it off grid
dont knw amount of daily load yet gotta get kw meter used 635kwh from grid lastmonth
I do have plans to add to system have the 10panels 24v wired to 48v
5strings up running to combiner
will be adding 6 more panels latter
greatest load is refridg
batteries are 2vx12 425amp hrs inverter is 2000watt aims modifed
panels wired with 8awg batteries wired with stranded wire two times larger
from batteries to converter using two mc truck battery cables
hope to be off grid thrught the nine months nice days tht are longer and maybe
even winter  thats our goal
Title: Re: charging batteries
Post by: Vic on December 26, 2016, 02:38:43 PM
Hi solar blue,  thanks for the important info.

First,  the Aims MSW inverter,  being MSW,  will generally not be good for most motors,  especially the one in the refer.   Most other loads would be OK.   Any Well pump would not like MSW,  either ...  think about changing that inverter.   And please,  ask here for opinions on specific inverters.  Many inexpensive inverters consume a lot of energy over a 24 hour period,  without any loads on them at all.   This load really adds up.

The wiring on your PVs,  at #8 AWG Copper should be fine,  unless this run is fairly long.   The wiring from the Combiner to the input of the Classic should be a minimum of #8 AWG Copper.   Normally we use standard,  stranded copper building wire  --  THHN.

For five strings of two of the CS 220s,  the DC breaker for the PV input the Classic would be 50A,  and the cable for the output of the Classic to the battery,  really should be #4 AWG Copper minimum,  with an 80 Amp DC breaker.   THHN #4 AWG (19 strand)  is the largest cable that will fit the blue Classic terminal block.

Your Grid AC loads for last month averaged,  about 21 kWh per day.  To try to use ALL of that power from Solar,  and probably much of it needing to come from a battery,  you would need a 48 V battery system,  and a huge battery.

Generally,  Grid power is cheap,  and  power generated from PV and batteries is very expensive.   So planning on using your existing battery to supplement Grid power is probably the best plan.

You could run an MNPV6 Combiner for now,  and add another later,  for the next 6 PVs,   BUT,  you would need an additional CC,  because 16 PVs  would overload one Classic 150,  on a 24 V battery system.

More later,  and the above are just my opinions ...   Vic
Title: Re: charging batteries
Post by: solar blue on December 26, 2016, 03:53:06 PM
       Vic
    Your opinion is good by me and greatly valued by me  I know little of inverters give me a thought on good ones having said that its off to the internet mall to hunt 

them the breakers i mean the 50 and 80amp breaker what type bx should i get to mount them in   if im rite i need a mnpv6 six 150bkers for it  two bx to place the 50 and the 80amp in rite
will replace inverter too
Title: Re: charging batteries
Post by: Vic on December 26, 2016, 04:48:48 PM
solar blue,

The MNPV6 Combiner will have one MNEPV type (DIN Rail) breaker for each string,  so five breakers in that Combiner box.  The MNPV6 has room for only six breakers,  so there would be only one breaker position that might be open (and that remaining slot could be taken up if you added a Surge Protection Device (SPD).

So for just this part of the installation,  you could use the Big Baby Box,  which can accept four DIN Rail breakers,  or the MN DCQuad box,  which uses a different type breaker  --  Panel Mount MNEPV breakers.  The DCQuad might seem preferable,  but it requires crimped lugs on the cables,  as those MNEPV breakers use studs for connections.   The MNEPV breakers use a screw terminal,  so no lug crimping is required.

AND,  if you use the Big Baby box,  there is an 80 Amp DIN breaker,  but it occupies two positions (it is twice the width of the 1 amp through 63 amp breakers).   With the Big Baby box there would be three breaker positions used.   Just thinking about this,  believe that the Big Baby box is rated for #6 AWG cable,  maximum.   These smallish boxes are fairly tight,  and trying to route #4 AWG cable could be a problem.  Believe that you could still route #4 AWG,  if you choose just the right spot for the 80 A output breaker ...   will look at the specs,  this evening.

There are a number of little details ...

More later,   Vic
Title: Re: charging batteries
Post by: Vic on December 26, 2016, 07:13:50 PM
Hi solar blue,

The Big Baby box is specified for a maximum breaker size of 63 A.  Using an 80 Amp breaker means that #4 AWG cable into and out of that breaker would be required,  and there is not a lot of room to spare to route cable that large.  With an 80 A breaker and #4,  an Inspector might not like that.   Your system will probably not be inspected ...
Here is a Link to the Manual:
http://www.midnitesolar.com/pdfs/big_baby_quad_manual.pdf

The MNEDC Quad box has a bit more room,  and if only two breakers are installed,  it should be fine,  as the MNEDC breakers,  in 80 A and 100 A ratings are the same size as those breakers with lower current ratings.

But,  with breakers that have stud-terminals, you would need to do good crimps on the terminal lugs that connect the cables to the studs.

Later,   Vic
Title: Re: charging batteries
Post by: solar blue on December 26, 2016, 11:34:07 PM
      Hi Vic
    Ok the quad it will be with an 80 and 50 amp breakers and the combiner box 15 amp breakers ok for that
what size power surge protector should  I get  Ill call solar electric and get this stuff on the Grey Hound  :D
Title: Re: charging batteries
Post by: Vic on December 27, 2016, 04:19:53 PM
Hi solar blue,

OK,  the SPD that could mount in the MNPV6,  will usually need one additional breaker.

Your maximum PV string  voltage with 2 PVs in series is about 85 - 90 V,  Voc,  depending on your temperatures.

Am in the middle of a project,  will check back later,   Vic
Title: Re: charging batteries
Post by: solar blue on December 27, 2016, 05:38:40 PM
  Hey Vic
       Got it all coming now. Get back at you when it all arrives thanks for helping
hope your project does well
talk with you when it all gets here


                                                                                        again much thanks
                                                                                              solar blue
Title: Re: charging batteries
Post by: Vic on December 27, 2016, 09:10:05 PM
Hi solar blue,

Thanks for the update.

All the Best for the New Year.

Vic
Title: Re: charging batteries
Post by: solar blue on December 28, 2016, 04:30:27 PM
     Hey Vic 
   battery bts arrived today plugged it in think its working .  didnt show  temp where would i find it?
I hooked up a shunt meter from another charge controler and checked it with a ge volt meter they agree the midnite is 2.5 greater can i calabrate the charger to that?
At night dark  the controler shows voltage coming in on input side with panels on   turn them off its goes down well almost away. what you think.
Title: Re: charging batteries
Post by: Vic on December 28, 2016, 07:58:00 PM
Hi solar blue,

Good that  you got the BTS.

On the Classic display (called the MNGP),  there  is a Temps menu.  If you are on the main status page,  press the Right soft button (the rectangular one,  above the other buttons.   "Network"  should show on the display.  Press the Left arrow button once.   The display should say Temps (or something similar).  Press Enter,  and on the lower right there should be an indication of the battery temperature.   If there is NO BTS,  this display should say "NO BTS",  or similar.

Am not certain just what you are saying regarding Calibrating the Classic.   Were you measuring current with that "shunt meter".   Did you add an external Shunt?   Or were you measuring a voltage?  Which voltage or current is it that you feel that needs a calibration?

It  is normal after Sunset for the Vin to show some voltage.   With a small - medium size PV array,  this voltage reading is about two thirds of the battery voltage.   Some PV arrays,  particularly larger arrays (IMO),  will show a lower voltage.   This is normal,  and should be of no concern.

Vic
Title: Re: charging batteries
Post by: solar blue on December 28, 2016, 08:53:47 PM
       Hi Vic
  Got ya on bts   and input  load after dark 
  hooked up a volt meter from another charge controler to batteries it shows 25.4 next i checked voltage with GE volt meter these two agree 25,4 now looking at batt voltage at same time on midnite classic it shows 1,5volt higher thats the best way i can explain it   do they sometimes require a calabration   
Title: Re: charging batteries
Post by: Vic on December 28, 2016, 10:30:52 PM
Hi solar blue,

Thanks for the added info.

While it is not unheard of,   it seems really uncommon,  that a Classic's battery voltage reading needs recalibration.

I have never seen a Classic that required recalibration.

Normally one would want to use a known-accurate Digital Multi Meter (DMM).  I would trust my Classic's battery voltage reading,   compared to a $30.00  DMM.

We do have a Lab Grade DC Voltmeter that is used as a Standard,  that other DMMs are compared against.

Think that this was asked before;

Did you purchase this Classic as a previously used one,  or was it new?   It could be,   that if it was used,  that the  previous owner had adjusted the Calibration.

Also,  check the Tweaks menu,  to see if any of the Offsets have been changed.   The Classic ships with voltage Offsets set to 0.0V.

Vic
Title: Re: charging batteries
Post by: solar blue on December 28, 2016, 11:08:22 PM
        Hi Vic

    Bought it new from missiouri wind and solar this nov
If offsets arent 0.0v should i set it there?
just set to 0.0 yep that did it ;D beside offset  what is vpv what should it be it is set at .05 i think



                                                                                                 Thanks Vic
Title: Re: charging batteries
Post by: Vic on December 28, 2016, 11:16:49 PM
Hi solar blue,

OK on the Classic being new in November.   But,  seems to me,  that the BTS should have been included,  as the info on the MidNite Solar site states that it is still included ...   hope that  you did not have to pay for the BTS.

Normally the Offsets are used to allow adjustments in how well multiple CCs work together.   These adjustments can help fine-tune when each CC (when there are multiple CCs) go to Float,   etc.

At least you should check the Offest values.   You should find them to be set to 00.0 V (IMO).

Thanks,   Vic
Title: Re: charging batteries
Post by: solar blue on December 29, 2016, 12:05:24 AM
       well called em they said no so i orded it from midnite solar  i set it at 0.0  beside that is Vpv
  .05 is that rite i may have done this dabbing round by accident
Title: Re: charging batteries
Post by: Vic on December 29, 2016, 12:29:07 AM
Hi solar blue,

OK on the BTS,  did look at the specs on the Classics,  last week.  It DID say on the MidNite Solar site,  that the BTS is still included ...   but glad that you have it on the system now.

You mentioned   .05.   There is the --5 mV Temperature Compensation value for your batteries.
This setting is in the Charge menu,  under " T-Comp '.   You will probably want to check that.

Vic
Title: Re: charging batteries
Post by: solar blue on January 05, 2017, 05:23:34 PM
      Hi Vic
 
  Got the breakers and mnpvbx got it up. Now got baby bx and 50 and 80amp lug breaker for it question is coming out of the combiner bx do I connect to load or line side of breaker before going into charge controler and which breaker is best for that purpose? The BTS has really helped
well it really made all the difference in my batteries

                                                                                            SB
                                                                                                       


Title: Re: charging batteries
Post by: Vic on January 06, 2017, 12:34:00 AM
Quote from: solar blue on January 05, 2017, 05:23:34 PM
      Hi Vic
 
  Got the breakers and mnpvbx got it up. Now got baby bx and 50 and 80amp lug breaker for it question is coming out of the combiner bx do I connect to load or line side of breaker before going into charge controler and which breaker is best for that purpose? The BTS has really helped
well it really made all the difference in my batteries

                                                                                            SB

Hi solar blue,

The MNEPV breakers  --  the DIN Rail breakers that have screw terminals for cable connections  --  are polarity sensitive,  so correct connection is important.   These are the type of breaker that is used in the Baby and BigBaby box.

In a PV combiner the + sign marked on the breaker connects to the PV positive output.

For the breaker at the input to the Classic,   the cable from the Combiner connects to the + sign of the breaker and the other terminal connects to the Classic PV in positive terminal.

The same breaker when hooked up to the battery circuit (not in a PV combiner) hooks up a little different. The + sign is connected to the battery plus.

The Panel Mount breakers (which mount to a panel with screws, are NOT polarity sensitive.

Does this answer your questions?   Vic
Title: Re: charging batteries
Post by: solar blue on January 06, 2017, 03:43:33 PM
       Hey Vic
   Ive wired the mnepv6 panels to the +side    So the switchs for the baby it doesnt matter which way the elec flows in and out a the breaker these face mount to box and have two studs one  marked LINE and the other marked  LOAD should LINE go out to battey or Load?  should the 80amp go between combiner and cc  and the fifty between the cc and batteries ? Those two breakers are all I like haveing it wired. Its been an experience for me thanks for your advice
and seeing me through it.  ;D

                                                                                                   Thanks for all your help Vic
                                                                                                                       
                                                                                                         
Title: Re: charging batteries
Post by: Resthome on January 07, 2017, 01:42:25 AM
Line is the positive.  As Vic said the MidNite panel mount breakers are not polarity sensitive like the DIN rail breakers are. Wire the panel mount breakers with the polarity as Vic mentioned above and you should be good.  Just remember that the Battery breaker positive (Line) goes to the Battery positive and the Load terminal of the breaker goes to the Battery positive block on the Classic. For the PV breaker the positive (Line) is connected to the positive cable coming from the combiner box. And the load terminal of PV breaker goes to the PV positive block on the Classic.

Edited: 

Assumed you have the Quad box with the screw mounts holes and the breakers mounts with screws.

Title: Re: charging batteries
Post by: solar blue on January 07, 2017, 08:13:15 PM
         Helo resthome

            Thanks thats the last two  breakers i gota wire then done, Yep screw for pv
         Quad bx. In the summer im going to 48v system so gota get new inverter just kinda wondering which one would be most economical when nothing is calling for
power is there something like that?  Think its best to find out whats is working best thats the best comparison I know how to do.
                                                                              Thanks again
                                                                                   Solar Blue
Title: Re: charging batteries
Post by: Vic on January 08, 2017, 06:41:46 PM
Quote from: Resthome on January 07, 2017, 01:42:25 AM
Line is the positive.  As Vic said the MidNite panel mount breakers are not polarity sensitive like the DIN rail breakers are. Wire the panel mount breakers with the polarity as Vic mentioned above and you should be good.  Just remember that the Battery breaker positive (Line) goes to the Battery positive and the Load terminal of the breaker goes to the Battery positive block on the Classic. For the PV breaker the positive (Line) is connected to the positive cable coming from the combiner box. And the load terminal of PV breaker goes to the PV positive block on the Classic.

Edited: 
Assumed you have the Quad box with the screw mounts holes and the breakers mounts with screws.

Hi John,

Thanks for correctly answering solar blue's question ...   I had read solar blue's,  "Now got baby bx",   as saying that a MN Baby or Big Baby box was going to be used for mounting breakers.   Had read the 80 A lug breaker,    as being the 80 A DIN double-wide breaker that has the copper screw terminals.

Sorry for my error.   
Thanks,   Vic
Title: Re: charging batteries
Post by: Resthome on January 08, 2017, 06:49:45 PM
No problem Vic. The confusion comes from the manual being one manual for both so both names are on the manual.

Title: Re: charging batteries
Post by: solar blue on January 09, 2017, 03:24:39 PM
       Hi John&Vic
     Its done and works great and done away with a bunch a wires and looks neater and through all this think im learning to type a little thanks much for hanging in with me to completion a this system. I would like to come to a point where i can use grid to supplement my system so questions are
1  will i have to go to 48v system to do this or stay with 24v?
2  can i take the 6 panels i have stored 24v wire to 28v and dedicate these to the fridg and a second battery bank?
3  elec water heater want be on it as i have made a thermo siv water heater that works from a wood stove and cloths dryer is coverted to 110v and gets heat from wood stove works very well.
4 which brings this question which inverter would be best for this and use less elec when there is no call for elec at night more input is better

                                                                                       Wayne




Title: Re: charging batteries
Post by: Vic on January 09, 2017, 06:14:02 PM
Hello Wayne,

Thanks for the update on your system.   Congratulations on getting it up and running!

Regarding questions 1 & 2,   There should be no need to go to a 48 V system,  to supplement some of your grid loads.   However,  a system can become a bit complex when trying to run from either Grid of some PV power.   Adding a second battery bank can be expensive,   and be another item that will need attending.

Most refers will require about a 1500 watt,  minimum Inverter rating,  to handle the fridge's compressor starting current surge.   There can be issues when trying to switch between  sources of AC power for a fridge,   unless this switch operates very,  very fast.   It is possible that using an inverter that has a fast,  internal transfer switch could help with this,   but these inverters are a bit expensive.

Just one point about PV panels.   Forget,  but are your PVs 220 watts?
The most common PVs are 60 cells,   and designed primarily for use on Grid tied systems.  Often these PVs have a maximum power voltage (Vmp)  around 29 - about 31 V.   These will usually require an MPPT Charge Controller(CC).   And,  one of these PVs (if this is the type that you have),   will not do a good job of fully-charging a 24 V battery,   so strings of two  would be required for 24 V,  and strings of  three PVs  would be needed for a 48 V system,   with an MPPT CC,  just FYI.

On Q3,   heating water takes a lot of energy.   Using an electric water heater for times when there is excess PV power available is often a good use of PVs,   but usually would need a medium or large sized system,  unless one is trying to heat only a small amount of water.

When it comes time for you to look at a new inverter,  or inverter/charger,   it would be a very good idea to know all of the details on what loads this system will need to supply,   when these loads occur (only when the sun is up,  or mostly from battery- etc),  and the peak loads, like starting a deep well pump,  Air Conditioning (A/C),  etc.

This design process is a bit detailed,  but very,   very important.   A good design,  based on your needs,   will help keep you from buying solar hardware that will not work,   or will work poorly for your intended purpose,   and might need to be replaced to accomplish your goals ...   and so on.

FWIW,   Vic
Title: Re: charging batteries
Post by: solar blue on January 09, 2017, 08:11:45 PM
        Hi Vic
       
    What would be the best device to use to aquire the load info on all appliances for this system and how long should i leave each appliance plugged to it for that purpose and would i
divide that by the amount a time to do it to get a daily avg? The fridg will be the only thing on
the six panels i have stored they will be wired to 48v totaling three strings will add two more
strings latter.
                                                       
                                                                                                           Wayne

Title: Re: charging batteries
Post by: Vic on January 10, 2017, 05:26:39 PM
Hi Wayne,   sorry for the reply delay.

For 120 VAC,   the Kill-A-Watt (KAW) meter is inexpensive,  and a good tool:
http://www.homedepot.com/p/P3-International-Kill-A-Watt-EZ-Meter-P4460/202196388?cm_mmc=Shopping%7cTHD%7cG%7c0%7cG-VF-PLA-D27E-Electrical%7c&gclid=CPCgqe7NuNECFQt_fgodiNQF8Q&gclsrc=aw.ds

The only inexpensive device like that I have used is the one above.   HomeDepot  markets at least one other,   which I have no experience using,   so,  would suggest finding a Kill-A-Watt.

The longer that it is connected to the load,  the more accurate it will generally be.  It has NO memory backup,   so if you have a power failure,  or it becomes unplugged during your measurements,  you would need to start over.

Some things,  like a refer,   will generally use a bit more power in Summer months,   but this depends upon the environment that the refer is in.

The KAW meter measures the current being drawn by the device being measured at the moment,   and measures and will show the kWh consumed over the period that the device has been connected,  until the KAW is unplugged,  so just write down the kWh number before the KAW is unplugged.

My opinion,   Vic
Title: Re: charging batteries
Post by: russ_drinkwater on January 13, 2017, 04:13:44 PM
I have a few similar devices which I purchased off evil bay.
These have been found to be extremely accurate in function when compared to the results of electrical testing
using data loggers from the power company here Ergon!
They will give you the amps draw of devices and as well keep a log of what the device has used.
A handy inexpensive tool! :o ;D
Title: Re: charging batteries
Post by: solar blue on January 18, 2017, 12:57:13 PM

        Hi Russ
       Thanks for info starting to get my kw usage down now that Vic got this thing chargeing like it should many many thanks to him for his help and everyone else too dont want to leave them out. Now got to buy a good inverter psw no charger needed in it. Im using a aims mod 5000 used it for 4 years it has been really good no trouble with it but fridg and washer doesnt like it at all some input on that would really good. Like to find one that would take a NAP when its not slaving.

                                                                                                       Wayne
Title: Re: HI BATT
Post by: solar blue on January 20, 2017, 09:27:38 PM
           I went out to check the batteries they have recovered well sg1300 now  then looking into charge menu I went into limits all was well.  The numbers were right  under that it said more
Well then i press right soft key  the words HI BATT then a value  of170 appeared MY HAIR STOOD
up I though it was temp a my batteries but not so I think
underthat says temp just under that shift that value can be adjusted but i dont i dont know what its for can someone help? I have watched all the instr videos on midnite site cant find it there read manul not there serched web cant find it any place
  its a classic 150sl solar only
                                                                                                       solar blue
Title: Re: charging batteries
Post by: Vic on January 20, 2017, 10:20:12 PM
Hi solar blue,

Believe that that setting is the temperature at which the Classic will stop charging the battery.   This would be used to keep the Classic's charging from heating the battery above that set temperature.

That very high setting is meant to disable this function,  unless the user sets it to a value of choice.

To see the temperature of the battery,   as measured by the BTS,  go to the " Temps " menu.   At the lower left of the MNGP display on the Classic,  you will see battery temp,   or similar.   This reading is in degrees C.

Good that your SGs are looking good.    Vic
Title: Re: charging batteries
Post by: solar blue on January 21, 2017, 12:00:23 PM
  Hi Vic
You think a value a 170is ok for that? Just want to tell you that system is charging beyond my expections even on completely over cast days it does its thing. Yesterday the sun shined a little while saw 1500watts out of it. This is going to work. I would like to say that i dont have my head warped round it yet but sure getting a head full  thanks for all the help and a thanks to west branch and rest home all yal are  great foke,Owe yal a cup a coffee if ever we should meet
thanks again guys
                                                                                                      Wayne


Title: Re: charging batteries
Post by: Vic on January 21, 2017, 02:07:54 PM
Hi Wayne,

170 should be fine ...  believe that setting is also in degrees C.   So it is the Default setting,  to make sure that it will never become active unless the battery is on fire.   Should be fine as it is,   unless you have a concern about your battery getting overcharged and becoming very hot.

Great news that your system is working so well for you  --  good work!

We are all learning,   and getting help from others here,   and elsewhere.
Have Fun,   Vic