2000k system only puts out 500 watt why?

[LETitROLL]

I still have a gut feeling though the voltage drop has something to do with the solder strip peeling up off the cell inside the panel or poor quality silicon if that is possible. I say poor quality silicon only because the cells themselves changed color from a really nice dark dark blue to a white blue almost white in three months of exposure to the sun. some of the panels changed color not all of them.

Those issues don't sound all that good, you need to compare the Voc on the panels and see if the ones that changed color the most have the lowest Voc? The panel I tested the other day was a 72 cell Mono (new), and I could not quite hit Voc, but because of the time of year I didn't think too much of it, I am at 46.25 lat. and even midday the sun is not all that high.

[charles2,david000k]

Just to let you guys know I did not forget about you I got the first meter in the mail yesterday night and have set it up to track the power output all day today since we are having a perfect day with absolutely no clouds and a cool temp of 69 to 68 today but am very unhappy with the amps it has been tracking for the day of 1.5 at my last check I am trying to check in and write down readings every hour but life is a busy thing.

[charles2,david000k]

Those issues don't sound all that good, you need to compare the Voc on the panels and see if the ones that changed color the most have the lowest Voc? The panel I tested the other day was a 72 cell Mono (new), and I could not quite hit Voc, but because of the time of year I didn't think too much of it, I am at 46.25 lat. and even midday the sun is not all that high.

Don't feel bad I was going to buy another panel of the same make and model but the manufacture pulled them all off ebay and the distributors have jacked their prices up sky high. An I refuse to buy another one of these panels unless it is directly from the manufacturer to avoid the warranty issue. If you don't buy direct they are not really warranted.

[charles2,david000k]

update 11/11/2015

Ok so I tested panels number one all day and these are my findings

10:15 am 35.43V 0.45A 15.9W at 69F

11am 34.70V 1.11A 38.5W at 69F

1:45pm 34.84V 1.24A 42.6W at 68F

2:40pm 35.09V 1.16A 40.06W at 68F

3:26pm 35.02V 0.96A 33.02W at 69F

4pm 35.02V 0.83A 29.02W at 67F

These reading below I am not quite sure of what they are I just wrote them down at the end of the day I will have to consult the operation manual. sorry for the edit. Wh=watt hours, Vm=minimum volts, Ah= Amp hours, Ap= Amp peak, Wp= Watt peak
Wh 239.
Vm 29.81
Ah 6.899
Ap 5.32
Wp 180.02
panels specs below

Nominal peak power(Pmax) 240Wp 245Wp 250Wp
Maximum power voltage(Vmp) 30.65V 30.8V 30.91V
Maximum power current(Imp) 7.83A 7.96A 8.09A
Short-circuit current(Isc) 8.36A 8.49A 8.62A
Open circuit voltage(Voc) 37.8V 37.98V 38.11V
Optimized cell efficiency(η） 17.00% 17.40% 17.60%

[sensij]

It looks like you are measuring an open circuit with a small leak. If your battery voltage and PV voltage are not identical, then you know that the PV array is not connected to the battery.

To take the battery condition out of the mix, you could first try measuring Isc for each panel.

When you are ready to do live testing with the battery, make sure it has discharged past the point at which you told your relay to turn off, below 23.9 V. Otherwise, the relay will be active, and will prevent your array from connecting to the battery. I would suggest returning the relay to its default settings (28.8 and 27.2 V) so that you don't need to discharge the battery so deeply to get the relay to turn off.

[charles2,david000k]

It looks like you are measuring an open circuit with a small leak. If your battery voltage and PV voltage are not identical, then you know that the PV array is not connected to the battery.

To take the battery condition out of the mix, you could first try measuring Isc for each panel.

When you are ready to do live testing with the battery, make sure it has discharged past the point at which you told your relay to turn off, below 23.9 V. Otherwise, the relay will be active, and will prevent your array from connecting to the battery. I would suggest returning the relay to its default settings (28.8 and 27.2 V) so that you don't need to discharge the battery so deeply to get the relay to turn off.

I have a ideal rolling around in my head that I think might work but am unsure and don't want to blow out this new watts up meter. connect the source wire directly to the panel like I did today then take the load side of the watts up meter and connect negative to positive. In my head this would work it would just be competing the circuit or am I crazy and going to blow my meter up?

[sensij]

I have a ideal rolling around in my head that I think might work but am unsure and don't want to blow out this new watts up meter. connect the source wire directly to the panel like I did today then take the load side of the watts up meter and connect negative to positive. In my head this would work it would just be competing the circuit or am I crazy and going to blow my meter up?

Yes, you've got it! To measure Isc with your Renogy meter (no battery involved), connect the + lead from the panel(s) to the Source Red wire, connect the - lead from the panel(s) to the Source Black wire. On the Load side of the meter, short the red and black wires together.

Edit:
Note that the meter is itself powered by whatever you are trying to measure, which could be responsible for some of the current you were measuring in the open circuit results you posted previously (although 40 W is much more than the meter alone should take). From the online manual, it looks like there is a way to provide auxiliary power to the meter so that it does not interfere with the measurement, but it isn't perfectly clear how to do it. The Isc test might not generate enough voltage to actually power the meter, so don't freak out if the meter doesn't turn on when you try it

[charles2,david000k]

Yes, you've got it! To measure Isc with your Renogy meter (no battery involved), connect the + lead from the panel(s) to the Source Red wire, connect the - lead from the panel(s) to the Source Black wire. On the Load side of the meter, short the red and black wires together.

Edit:
Note that the meter is itself powered by whatever you are trying to measure, which could be responsible for some of the current you were measuring in the open circuit results you posted previously (although 40 W is much more than the meter alone should take). From the online manual, it looks like there is a way to provide auxiliary power to the meter so that it does not interfere with the measurement, but it isn't perfectly clear how to do it. The Isc test might not generate enough voltage to actually power the meter, so don't freak out if the meter doesn't turn on when you try it

Ya its a three pin connection I found one on a old pc board I had laying around and it takes a 4.8v to 60v input on the three pin input but I am just going to wire a 9 volt to it. But anyone else who tries this remember you have to remove ALL power to reset the meter's memory. I just personally see no point in spending 9 10 buck on something I already have. yep just did it the 9 volt works great! I will redo the readings on panel number one this sunday rain is supposed to move in early morning and hang around till saturday night.

[charles2,david000k]

another question which I keep forgetting to ask is I have a old school analog meter. The residential kind that goes on the outside of your home when the meter guy us to come to your home and read the thing before smart meters took over. I got a brand new one never used still in the box will it accurately read DC power output? I originally got it to put between my inverter and 200amp service panel either way I am going to use it but I thought it would be a interesting question due to the fact the guy on ebay who sold it to me had no ideal.

[Mike90250]

The old spinning disk meters will NOT work with DC. They use the AC to induce eddy currents in the aluminum disk which makes it rotate.

[almac]

Ok so I tested panels number one all day and these are my findings

10:15 am 35.43V 0.45A 15.9W at 69F

11am 34.70V 1.11A 38.5W at 69F

1:45pm 34.84V 1.24A 42.6W at 68F

2:40pm 35.09V 1.16A 40.06W at 68F

3:26pm 35.02V 0.96A 33.02W at 69F

4pm 35.02V 0.83A 29.02W at 67F

These reading below I am not quite sure of what they are I just wrote them down at the end of the day I will have to consult the operation manual. sorry for the edit. Wh=watt hours, Vm=minimum volts, Ah= Amp hours, Ap= Amp peak, Wp= Watt peak
Wh 239.
Vm 29.81
Ah 6.899
Ap 5.32
Wp 180.02
panels specs below

Nominal peak power(Pmax) 240Wp 245Wp 250Wp
Maximum power voltage(Vmp) 30.65V 30.8V 30.91V
Maximum power current(Imp) 7.83A 7.96A 8.09A
Short-circuit current(Isc) 8.36A 8.49A 8.62A
Open circuit voltage(Voc) 37.8V 37.98V 38.11V
Optimized cell efficiency(η） 17.00% 17.40% 17.60%

when i tested my panels for current i just used a $10 multimeter, put the switch to the 10amp position then put the red pin to the +ve on the panel and the black pin to the negative on the panel. the meter read 9amps when the panel was in full sun. that is the rating for the panel.. 9amps. the wires on my cheap multimeter instantly smoked. have you tried this method?

[sensij]

when i tested my panels for current i just used a $10 multimeter, put the switch to the 10amp position then put the red pin to the +ve on the panel and the black pin to the negative on the panel. the meter read 9amps when the panel was in full sun. that is the rating for the panel.. 9amps. the wires on my cheap multimeter instantly smoked. have you tried this method?

He did, and probably damaged his meter because he had several panels in parallel. It was discussed several pages ago.

[charles2,david000k]

The old spinning disk meters will NOT work with DC. They use the AC to induce eddy currents in the aluminum disk which makes it rotate.

Ok good to know AC power only.

[charles2,david000k]

loop test started 11/13/15

We got some really good weather today clear blue and no clouds so I decided to start testing again early. But as of 10:42am I was only getting an amp reading of 4.2 amps of current from panels number 1 temp 52F the same panel I tested last. Isc is 8 but it is still early and we will see what she peaks at around 12 to 2 pm high noon.

[jflorey2]

We got some really good weather today clear blue and no clouds so I decided to start testing again early. But as of 10:42am I was only getting an amp reading of 4.2 amps of current from panels number 1 temp 52F the same panel I tested last. Isc is 8 . . .

Sounds about right. Isc is the important number. Multiply Isc by Voc and that will give you theoretical max power. (Actual peak power will be somewhat less than that but not by much.)