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Battery talk (A place to discuss any and all battery technologies where the discussion may not fit into other topic areas) => Lead Acid (Sealed and flooded) => Topic started by: Matrix on November 23, 2017, 10:57:25 PM

Title: Wondering why my charge current is so hi
Post by: Matrix on November 23, 2017, 10:57:25 PM
I have a hybrid Conext SW Inverter / Charger.  The charger is run off of an incoming AC line (Gen or Line power).    It is capable of charging at 90 amps.   The batteries are Trojan L16H-AC 435 ah batteries. 

Doing some calculating,  it is my understanding that you should not charge the batteries at a rate higher than C/8 .... or about 54 amps.  And yet,  when I set the SW to charge,  and set my battery type to custom using 29.8v Bulk / 29.6v Absorb / 27v float ... when I start a charge at about a 55-65% SOC on the battery, the charger goes to Bulk and the charge amps shot up to 85+ amps. 

There is no way to control amps,  only volts in the charger.  (in the Classic 150  I could set an Amp Output limit).    I thought C/8 (54 amps)  was about the max I wanted to charge this 435ah 24v battery bank at.   If I lower the charge volts,  the batteries never fully charge as test with hydrometer.   But even if I do lower the volts the amps are still very hi.  Like about C/5.

  Help me understand what i am missing here.

Title: Re: Wondering why my charge current is so hi
Post by: mike90045 on November 24, 2017, 12:01:31 AM
isn't there a setting for battery amp-hour size?
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 24, 2017, 08:37:55 PM
Quote from: mike90045 on November 24, 2017, 12:01:31 AM
isn't there a setting for battery amp-hour size?
Yes. I have it set to the battery size... 435ah.   I guess I could lower it and see what happens. If that lowers the amps
Title: Re: Wondering why my charge current is so hi
Post by: mike90045 on November 25, 2017, 12:30:01 AM
there may be interacting settings, breaker size. battery size, generator size.    Go through your manual and see if Schneider has hidden any tidbits regarding those settings.  They are pretty obtuse about them.
Title: Re: Wondering why my charge current is so hi
Post by: CDN-VT on November 26, 2017, 01:35:17 AM
@matrix
Do you have a Schneider Electric Conext XW+/SW System Control Panel (SCP) ?
under advance you will find limits on charge & steps of charging . Or Conext Combox for Network Monitoring and Remote Access with a laptop.
I have a 6848 stack that im about to commission in , but i'm needing a BTS that I might of left @ the Midnite plant .

The trick to see advance is hold 3 buttons on meters enter ,Up & Down  advance shows , that works under charge also & a few places .
Like 141 for Outback

VT
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 26, 2017, 01:32:41 PM
Quote from: mike90045 on November 25, 2017, 12:30:01 AM
there may be interacting settings, breaker size. battery size, generator size.    Go through your manual and see if Schneider has hidden any tidbits regarding those settings.  They are pretty obtuse about them.
Schneider is Obtuse about a lot of things.  Terrible Manual
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 26, 2017, 01:37:02 PM
Quote from: CDN-VT on November 26, 2017, 01:35:17 AM
@matrix
Do you have a Schneider Electric Conext XW+/SW System Control Panel (SCP) ?
under advance you will find limits on charge & steps of charging . Or Conext Combox for Network Monitoring and Remote Access with a laptop.
I have a 6848 stack that im about to commission in , but i'm needing a BTS that I might of left @ the Midnite plant .

The trick to see advance is hold 3 buttons on meters enter ,Up & Down  advance shows , that works under charge also & a few places .
Like 141 for Outback

VT
Hi VT,
Yes I use the Advanced settings and have the SCP and also have a battery monitor.  I am actually setting up and using the charger with Custom settings so that it is set up with the exact voltages thru the charge cycle that are called for my Trojan.  But when it starts charging the amps get really hi.  Like 90+ which is way over C/8 as recommended for the battery.   And it does this regardless if I use custom or the Flood battery type setting.

So I am going to try and lower the Amp Hour of the Battery setting to a value lower than my actual Amp Hours of 435 and see if that causes the charger to pump less amps.   
Title: Re: Wondering why my charge current is so hi
Post by: Westbranch on November 26, 2017, 01:47:40 PM
Matrix, how long does the unit deliver the >90Amps? Does it not decrease over time?
Title: Re: Wondering why my charge current is so hi
Post by: russ_drinkwater on November 26, 2017, 02:51:35 PM
I have not read my trojan info for a while, but isn't the charge rate of 20-40% of
rated amps the go?
If so what your charger is delivering is just a tad over recommended minimum.
If wrong I stand corrected.
The L16 trojans we have here are apparently the newer AC ones (with the carbon).
Same question as well, does the charge rate taper off after a while?
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 26, 2017, 08:39:46 PM
Quote from: Westbranch on November 26, 2017, 01:47:40 PM
Matrix, how long does the unit deliver the >90Amps? Does it not decrease over time?
It does 90 + in the bulk stage for about 1.5 hrs.  Then yes, it tappers in absorb down from 90+ to 7.5 amps over 2.5 hrs. 
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 26, 2017, 08:41:33 PM
Quote from: russ_drinkwater on November 26, 2017, 02:51:35 PM
I have not read my trojan info for a while, but isn't the charge rate of 20-40% of
rated amps the go?


I have not ever seen a charge rate spec of 20-40% ... but it could be?
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 26, 2017, 08:45:25 PM
Here is my charge cycle over the course of about 4 hours. 
Title: Re: Wondering why my charge current is so hi
Post by: mike90045 on November 26, 2017, 09:13:29 PM
Quote from: Matrix on November 26, 2017, 08:39:46 PM
Quote from: Westbranch on November 26, 2017, 01:47:40 PM
Matrix, how long does the unit deliver the >90Amps? Does it not decrease over time?
It does 90 + in the bulk stage for about 1.5 hrs.  Then yes, it tappers in absorb down from 90+ to 7.5 amps over 2.5 hrs.

Man, you are running your batteries down way too low, for them to be charging that hard.  If they are not getting warm, you are likely OK, but if they are getting hot, you are killing them.

Quickly running the math backwards, you are putting in about 150Ah, so if you are only discharging 20% daily, your battery bank is about 650ah ?? 

At least the charge tapers way down, and that means the batteries are still healthy.
Title: Re: Wondering why my charge current is so hi
Post by: CDN-VT on November 26, 2017, 09:15:48 PM
Same screen as type of charge with the System Control Panel (SCP) under advance
Scroll down to rate & amount of charge  .

It's worded wrong !
Cnglish  manual , hence why the tech support is bad.

VT
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 27, 2017, 11:13:34 AM
Quote from: mike90045 on November 26, 2017, 09:13:29 PM
Man, you are running your batteries down way too low, for them to be charging that hard.  If they are not getting warm, you are likely OK, but if they are getting hot, you are killing them.

Quickly running the math backwards, you are putting in about 150Ah, so if you are only discharging 20% daily, your battery bank is about 650ah ?? 

At least the charge tapers way down, and that means the batteries are still healthy.
I have 4 Trojan L16H-ACs that are in series and have 435ah.  When charging I have never seen the temp get higher than 90*F.  For the graph above the highest the temp ever got was 88*F

Here is what we have today (and this is my typical amount of daily depth of discharge):
- SOC measured by both the Whiz Bang Jr and SW Battery monitor: 68% SOC
- SOC measured by SG average all 12 cells: 1.221 which according to Trojan is just about 72% SOC (1.217 = 70%)
- Battery Temp: 76F using SW sensor on post / 67F using CC sensor on side in between batteries (out side air temp is 51F)
- Amp Hours used 139ah (according to SW battery monitor)

I only use the SW for charging every so often (like when there has been no sun).  So over 40 days of use since I started new with these batteries,  I have only every used the SW at its 90+ charge amps about 8 times at most. Most of the time I charge via the solar CC which never goes above 60 amps.

But I did figure out why the charge amps was running so hi when charging from the Conext SW 4024.  (see next post)


Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 27, 2017, 11:21:27 AM
Quote from: CDN-VT on November 26, 2017, 01:35:17 AM
@matrix
Do you have a Schneider Electric Conext XW+/SW System Control Panel (SCP) ?
under advance you will find limits on charge & steps of charging . Or Conext Combox for Network Monitoring and Remote Access with a laptop.
I have a 6848 stack that im about to commission in , but i'm needing a BTS that I might of left @ the Midnite plant .

The trick to see advance is hold 3 buttons on meters enter ,Up & Down  advance shows , that works under charge also & a few places .
Like 141 for Outback

VT

Quote from: CDN-VT on November 26, 2017, 09:15:48 PM
Same screen as type of charge with the System Control Panel (SCP) under advance
Scroll down to rate & amount of charge  .

It's worded wrong !
Cnglish  manual , hence why the tech support is bad.

VT
Ding Ding Ding Ding ....

That was it!   And it was not worded wrong.  I mis-read it.  How in the heck did I do that??  I had it set to 100% Rate of Charge.  Some how I read that to mean "do you want the charger to charge the battery back to X%" so I set it to 100% thinking I want it to charge back to 100% SOC. 

As you noted,  it is a % of the chargers total Charging amp capacity.  The SW 4024 has a charge capacity of 90 amps,  so setting it a 100% (as I had) was saying to the SW "charge at 90+ amps" ... Doh !!   ::)

I set it to 60% this morning  ... and "Magically" it began the bulk charger at a Max  of 54 amps.   (90 amps x .60 = 54 amps).  Thanks for pointing that out. 

So now my next question,  do I want the Charge Rate set at 60% which would be a max charge amps of 54 ... or do I want it set a bit higher than 54 amps (60%) since it will only hit that max during bulk and then start to taper down from there once it goes into Absorb?
Title: Re: Wondering why my charge current is so hi
Post by: CDN-VT on November 27, 2017, 10:10:35 PM
Im use to Outback wording & Midnite , Trace is different also .Conext manual is a hard read , but I find the updates of PDF have fixed many typos or things. I'll edit this after I read your cell construction

VT

Quote from: Matrix on November 26, 2017, 08:39:46 PM

It does 90 + in the bulk stage for about 1.5 hrs.  Then yes, it tappers in absorb down from 90+ to 7.5 amps over 2.5 hrs.

Here I would keep it set where you have changed it to (54amps) and now monitor the water usage. Im sure @ 90 amps for 1.5 hrs , water has been added .
You need to stir , but not boil the H2so4 out.
Age of cells will change the  water usage , so the recharge is adjust also (in my world).

No Solar panels ? just using grid ? WHY ?

VT
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on November 28, 2017, 11:22:16 AM
Quote from: CDN-VT on November 27, 2017, 10:10:35 PM
Im use to Outback wording & Midnite , Trace is different also .Conext manual is a hard read , but I find the updates of PDF have fixed many typos or things. I'll edit this after I read your cell construction

VT

Quote from: Matrix on November 26, 2017, 08:39:46 PM

It does 90 + in the bulk stage for about 1.5 hrs.  Then yes, it tappers in absorb down from 90+ to 7.5 amps over 2.5 hrs.

Here I would keep it set where you have changed it to (54amps) and now monitor the water usage. Im sure @ 90 amps for 1.5 hrs , water has been added .
You need to stir , but not boil the H2so4 out.
Age of cells will change the  water usage , so the recharge is adjust also (in my world).

No Solar panels ? just using grid ? WHY ?

VT

Oddly ... I have never had to add water in 40 days since I started using these batteries New,  even occasionally charging at 90 amps.  The water level in the cells can new from the Trojan factory full to the bottom of the fill tubes,  and they are just now after 40 days at 3/16" (less than .5 cm) from the bottom of the fill ring.  Trojan says "Full" is 1/4" from the bottom. 

So 54 amps (60% of the SW 4024's  charge capacity) should be the best place to keep the SW setting? 

And Yes I have solar panels.  I am just using this charger for EQ charging and for when there is no Sun on cloudy days.  My entire set up is found in summary in my signature below, and can be seen in its entirety with pictures here (http://midniteftp.com/forum/index.php?topic=3907.msg37991#msg37991)
Title: Re: Wondering why my charge current is so hi
Post by: CDN-VT on November 29, 2017, 05:20:03 PM
I followed the link & liked the system .
So why are you asking the conext to charge the battery rather than let the solar do it & then grid feed back & turn the meter backwards ?
Whats your reasoning / here were in the PNW (Please Now Wet) and I see grey all day & then at night I get full moons & stars !!
Im now thinking I should of got those night solar panels .
VT
Title: Re: Wondering why my charge current is so hi
Post by: Matrix on December 07, 2017, 10:32:26 AM
Quote from: CDN-VT on November 29, 2017, 05:20:03 PM
I followed the link & liked the system .
So why are you asking the conext to charge the battery rather than let the solar do it & then grid feed back & turn the meter backwards ?
Whats your reasoning / here were in the PNW (Please Now Wet) and I see grey all day & then at night I get full moons & stars !!
Im now thinking I should of got those night solar panels .
VT
Because I do not have a grid tied system.  So I cannot back feed to the main power grid.
Title: Re: Wondering why my charge current is so hi
Post by: CDN-VT on December 07, 2017, 11:40:43 AM
Ahhhhhhhhh
Thanks
VT