Panels showing 18 V low or no amps - why?

[mocars2]

I bought 6 DIY panels this guy put together last fall. At that time I just checked each one's no load volts, and all were 18 plus to 20 volts. Now I've hooked them up to a charge controller and in bright sun with a battery that can accept a charge (12.9)- all show 18 v plus - one shows .7 amps; another .8 amps and a 3rd 0 amps. the other 3 show 1.5 plus and up.
So I checked each one separately through the controller connected to a battery (pretty new) with 12.9 volts. So I know I've got them hooked up right since all I'm doing is connecting the pos, and neg from the panels to the controller and checking the output of each one the same way; then disconnect that one and connect the same pos and neg wire to the controller and checking those amp on the next panel,.......

So what would cause a panel to show volts and no amps? AND what can I do to fix this. Each pane has 37 3 x 6 cells.

[SunEagle]

I bought 6 DIY panels this guy put together last fall. At that time I just checked each one's no load volts, and all were 18 plus to 20 volts. Now I've hooked them up to a charge controller and in bright sun with a battery that can accept a charge (12.9)- all show 18 v plus - one shows .7 amps; another .8 amps and a 3rd 0 amps. the other 3 show 1.5 plus and up.
So I checked each one separately through the controller connected to a battery (pretty new) with 12.9 volts. So I know I've got them hooked up right since all I'm doing is connecting the pos, and neg from the panels to the controller and checking the output of each one the same way; then disconnect that one and connect the same pos and neg wire to the controller and checking those amp on the next panel,.......

So what would cause a panel to show volts and no amps? AND what can I do to fix this. Each pane has 37 3 x 6 cells.

Before I can provide you with any direction I need some more information.

How did you wire the 6 panels to the Charge controller? Are they parallel or series or both?

What is the make and model of the Charge controller? Depending on what input voltage it is rated for will require your panels to properly wired to it.

A battery at 12.9 volts is full and happy and doesn't really need to be charged so technically there isn't any load on your charger or panels which may be one reason your panels are not producing any amps on the one panel.

Another reason is that the panel with 0 amps can't handle any load . It is the same thing as if you had a battery that shows voltage but when you hook it up to a light bulb the battery drops to zero volts. The battery does not have the ability to power the light bulb but will show some voltage at no load.

[Sunking]

I bought 6 DIY panels this guy put together last fall. At that time I just checked each one's no load volts, and all were 18 plus to 20 volts. Now I've hooked them up to a charge controller and in bright sun with a battery that can accept a charge (12.9)- all show 18 v plus - one shows .7 amps; another .8 amps and a 3rd 0 amps. the other 3 show 1.5 plus and up.
So I checked each one separately through the controller connected to a battery (pretty new) with 12.9 volts. So I know I've got them hooked up right since all I'm doing is connecting the pos, and neg from the panels to the controller and checking the output of each one the same way; then disconnect that one and connect the same pos and neg wire to the controller and checking those amp on the next panel,.......

So what would cause a panel to show volts and no amps? AND what can I do to fix this. Each pane has 37 3 x 6 cells.

Well if you are connecting to a battery that shows 12.9 volt disconnected and rested it is fully charged up and will not take current other than float. What is the voltage of the batteries with p[anels and CC connected in full sun light. If it reads 13.6 the CC is in float mode which means the battery is fully charged up.

[mocars2]

Well if you are connecting to a battery that shows 12.9 volt disconnected and rested it is fully charged up and will not take current other than float. What is the voltage of the batteries with p[anels and CC connected in full sun light. If it reads 13.6 the CC is in float mode which means the battery is fully charged up.

The 12.9 was through the controller - it was about 12.5 alone, but through the controller at 12.9 it wasn't in float mode yet. The controller will show 14 before it goes into a float mode. So a controller connected to a battery at 12.5 alone 12.9 connected, and only connecting 1 panel at a time - getting the reading then disconnecting it and connecting the next one (alone)- get that reading , disconnect and move on, and as I said above - 1 is .7 another is .8; 3 are 1.5 and one shows volts but no amps.

[mocars2]

So if the battery isn't full and controller is working correctly and we're checking each panel separately - what are some of the common causes for some panels to show low or no amps but show 18 (no load) volts.

[inetdog]

So if the battery isn't full and controller is working correctly and we're checking each panel separately - what are some of the common causes for some panels to show low or no amps but show 18 (no load) volts.

Are there bypass diodes in the panel? If not, then one or more damaged cells could be limiting the available current, but still providing normal open circuit voltage. (Think of it as a whole bunch of large cells in series with one of the cells replaced with one 1/100 the size. Not a lot of current will flow.)

[green]

So what would cause a panel to show volts and no amps? AND what can I do to fix this. Each pane has 37 3 x 6 cells.

I can answer this one for you. One bad cell. When building a DIY panel you must test each cell the best you can to weed out any cells that aren't producing good current. Bad cells will usually produce there rated voltage, it's the amps you need to pay close attention to when building your own panel. Every package of B-Grade cells I've bought of EBay has had at least one or two bad cells in them. If you don't test them and just slap them together it will ruin your whole panel.

[mocars2]

I can answer this one for you. One bad cell. When building a DIY panel you must test each cell the best you can to weed out any cells that aren't producing good current. Bad cells will usually produce there rated voltage, it's the amps you need to pay close attention to when building your own panel. Every package of B-Grade cells I've bought of EBay has had at least one or two bad cells in them. If you don't test them and just slap them together it will ruin your whole panel.

That's what I was afraid of. my guess is he checked the volts and saw it seemed right but never checked the amps.
He sandwiched the cells between 2 pieces of store bought glass and used what looks like silicone at each soldering point and in between each cell and around the whole outer edges. He said he shot some sort of gas - natural gas of helium or something before he sealed it to get rid of any condensation. Would anyone have an idea what he used?With this siliconed like this - will I ever be able to pull it apart and check each cell?