Where are the Watts? Classic Lite 150

[BlueSolar]

Hello all;

New to Solar and this is my first post so the noob in me will surely shine through!

OK I have a Classic Lite 150 installed, the Local App software up and communicating with my PC. 2 Flooded Trojan 6v batteries wired in series for a 12v set.
I am working with 6 small solar panels, wired in series as a test bed before I go big. The panels are Power Film PT15-300 that each are rated at 15.4v, 3.08 watts, VOC 19v and ISC 250ma.

They are wired in series and I do see the +/- 100 volts on the Local App going into the Classic Lite.

Screen shot attached of the graph of a recent cloudy day.

So where are the watts? I have set the Live Data to track and graph the input volts and the watts and only see the volts.

Is there config settings I need to change? The Manuals have not helped me in this area. 

Looking forward to your input...

[Westbranch]

you are getting voltage and NO Amps, so Volts x Amps  =  Watts, on cloudy , overcast days you will not see much input at all. 
Just check you connections for a loose one in case that is causing an issue, otherwise things look about average...

hth

battery is 11.7  that is close to a DEAD battery voltage

[BlueSolar]

Thank you West,

Can I get the volts into the system and no amps if I have a bad connection in one of the panel wiring?

[Westbranch]

No amps  means NO WATTS.. so there is nothing to go in based on what your Local App is showing.   A poor connection 'may' exist and it might have an effect on what your system is seeing, but on an overcast day at this time of the year unless you are nearer the equator than I there is very little coming in in the first place.  Also since you are not getting up to Vmp that is another indication that there are no amps being made.

First comes the voltage, once above Vmp the amps , generally, start to show when the sun is weak. Bright sun is a bit better as the voltage will climb very fast and you probably will miss the rise.

BTW you need to put a charger on that battery or it is going to be a yard ornament.  How long has it been since it was charged?
Where are you located? Recent temps?

ADD:  I just relooked at the specs, and the Isc is so low you might never see it show on the LA, but you would see the watts.  What is the Imp?
ps as you know you add V in series but you only get  the Imp of 250mA

[BlueSolar]

Yes I caught that about the battery bank, thank you, and yes there was a charger on it 5 mins after I saw your post. 

I am on Vancouver Island, BC, Canada. Temperatures on the date of the screen shot were +2c to +10c.

Yes, I am aware that in series I get the stacking of the volts and not the amps. Is it worth it to try a parallel set up to drop the volts but boost the amps on these small panels?

My limited understanding of the MPPT controller is that it favours the higher voltage rather than the (slightly) higher amps of this series connection rather than the parallel set up.

"ADD:  I just relooked at the specs, and the Isc is so low you might never see it show on the LA, but you would see the watts.  What is the Imp?
ps as you know you add V in series but you only get  the Imp of 250mA"

Where do I find or measure the Imp as I do not see it on the spec sheet of the panel?

[Resthome]

If you had only 25% sun the I curve for these panels you would only get 50ma that is  0.050Amps. Even at max sun you are only going to see 200ma or 0.20 Amps in with these panels all in series. Try 3 parallel strings of two in series that might give you 600ma or 0.60A  I think these panels are way to small for the Classic. The scale you see on the LA is too large to show any of the low watts out. Graph watts only and see what it shows. I'm not sure what Andrew has for the lowest scale.

[Westbranch]

lost a long post , too long to redo...

go to  http://www.wegosolar.com/pages.php?pageid=5
you need a combiner box to run 6 in parallel

Mppt good for sending high V a long distance and then down converting to battery voltage. Keep PV battery and CC as close as poss = best setup.

You are on the 'wet coast' I am in the interior about 6 hr drive North.

RH has said some of the rest

hth

[Vic]

Hi Blue ..,

For a large MPPT Charge Controller (CC) like the Classic,   you do not have nearly enough PV power to even begin to charge a battery.    To make any large MPPT CC work,  you will need about 10 - 15 watts to run the internal Converter of the CC.

Your six 3 W PVs might produce about 12 -14 watts under ideal conditions ...

As a general rule,  MPPT CCs begin to make sense at about 400,  or so watts of PV power.

For a better test,  you would probably want at least one 200-ish watt PV (with about a 36 Vmp rating),  and,  better yet,  two or so.   A good goal for PV array size is to shoot for at least 5% of your battery's 20-Hour Capacity,  and better yet,  10% of C.

FWIW.  You DO have the best CC made,  so hope that you can add some PV power.   Good Luck,   Vic

[vtmaps]

Where do I find or measure the Imp as I do not see it on the spec sheet of the panel?

The wattage rating of the panel divided by the Vmp equals the Imp

3.08 watts ÷ 15.4 volts = 0.2 amps = 200 milliamps.  That is about 80% of the Isc.

As Resthome and Vic have mentioned, you don't have enough panel to run the classic, let alone charge the battery. 

--vtMaps

[boB]

You do have a very very small PV array there but try this....

Parallel connect the 6 total PVs in 3 strings of 2 panels in series.

That should be around 36 volts open circuit.

Then, change the MODE from Solar to Legacy P&O.  I'm not sure if
SOLAR mode will track that small of an array well.

So, with say, 31 Voc, your Max power point voltage should be around 76% of that, or,
about 23 volts.

Or, you might try Hydro mode but use the Manual MPP V and set it to 23 or 24 volts.

OR, Percent Voc and set that to 76 or 80% and see if you get something out of it.

It's real close to not getting anything but a lower input voltage should help, and 2 in series
is way better than just running them all in parallel or all 6 in series for a 12V battery.

If it's sunny, you might see "something" out of that PV.

boB

[BlueSolar]

Thank you all for the good and experienced input. 

I will be on my mini array today, in particular I will arrange boB's setup recommendation. I will post some results if I get a better 'picture'.

In addition, as a few have suggested, these are not the right panels in fact for this test so I will be looking at purchasing a better set later this week.

cheers 

Blue

[Westbranch]

So I will be looking at purchasing a better set later this week.
cheers 
Blue

OK So what are you going to do with your System?  THIS NEEDS TO BE THOUGHT OUT SO THAT WHAT YOU GET WILL MEET FUTURE NEEDS! so you do not make a snap decision...based solely on price or whatever.

[BlueSolar]

Update.

Some progress today with the input received. As an intermediate step I did rewire for a full parallel set up and the with the sun poking through for a few minutes here in the Pacific North West the Classic Lite 150 did manage to record .1 and .2 amps for a total of 2 watts stored.    See the attached screen shot.

I know it is not much but this is a test bed for me. 

I then made the change in the config tab of the Local App to  Legacy P&O, saw no change and changed back to Solar. This rapid change was not the best idea as the Classic Lite changed to RESTING ABRUPT MODBUS CHANGE and stayed there until I powered it down for the next array rewire. I surmise that I should have waited in Legacy a bit longer.

Powered down and disconnected from the battery bank and made the second change. I am now at 3 sets in parallel of 2 panels each set in series.

On powering up the Classic Lite is in RESTING (111:UNKNOWN). I will assume that this is due to light conditions are not enough for it to resume operation?

Light conditions are now to low for any valuable input so we shall see what tomorrow brings.

To your question and suggestion Westbranch, yes I concur, I will take a go slow approach and if I can get enough watts in the small panels for my testing then I will not need to jump up to higher watt panels right away.

I spoke with Midnite Technical today as well as they were responding to a previous question and they agreed with the recommendations boB had made. So all good so far.

Time to celebrate my 1 watt!

Input comments and suggestions always are appreciated.

Blue 

[boB]

As for Reasons for Resting,  "RESTING ABRUPT MODBUS CHANGE" typically means that the battery charging voltage
set point has changed a large amount in one step (10+ volts in one swoop) while it is running...
  Incrementing the charge voltage amounts in less than 10 volt amounts doesn't cause that.
That reason to go to resting is so that if someone changes the nominal battery voltage while it is running,
it will not be quite as easy.  But if you were just using the Classic normally, I do not understand
why it would do that.

As for Resting 111:unknown, 111 is what comes up every time the Classic powers up.  I guess that the
Local App doesn't know that quite yet.  Too bad the graph doesn't show the input voltage along with the watts.

boB

[Robin]

I'm sorry, but you need to put a real solar panel on your test system. You cannot test it without a real solar panel. We cannot devote anymore of Bob's time to this unless a real solar panel is connected. Bob is trying to work on an inverter design and this is not helping much.
Sorry for sounding grumpy, but we need Bob to be working on the inverter.