Low amps from solar panels

[bcbob]

I have 2 Renogy 100 watt solar panels flat mounted on my motor home.
19.9 volts from panels to charge controller with a 30 amp inline fuse between panels and CC. Charge controller is a 30 amp PWM. My question is.....the panels can produce up to 5.62 amps each, but are now only producing between 2-4 amps in mid day full sun. Any suggestions on what can be done short of getting on the roof? The volts coming from the panels seem OK, but the amps are way low. Up until a few days ago I was getting between 9-10 amps. Panels are in parallel.
When I remove the inline fuse my amp meter will read the same as the CC.

[Almot]

They will eventually tell you to get 800W solar 🙂

Check the battery charge DIRECTLY. With hydrometer.

[red31]

bcbob wrote:
The volts coming from the panels seem OK,

what does that mean?

if the panel volts are higher than the battery, the controller is limiting the current to the batteries, ie absorption or float.

[NinerBikes]

bcbob wrote:
I have 2 Renogy 100 watt solar panels flat mounted on my motor home.
19.9 volts from panels to charge controller with a 30 amp inline fuse between panels and CC. Charge controller is a 30 amp PWM. My question is.....the panels can produce up to 5.62 amps each, but are now only producing between 2-4 amps in mid day full sun. Any suggestions on what can be done short of getting on the roof? The volts coming from the panels seem OK, but the amps are way low. Up until a few days ago I was getting between 9-10 amps. Panels are in parallel.
When I remove the inline fuse my amp meter will read the same as the CC.

You might get 5.5 amps from panel if the panel was portable, and aimed directly at the sun. Laying it flat on the roof, where it can get dusty and dirty, will not produce anywhere near the rated amperage. Clean panel with windex and aim directly and the sun, and see if in the late morning you are getting rated amps, when battery charge is low.

100w is nowhere near enough for 4 batteries.

[JFNM]

Hi bcbob, I agree with the others about the typical OEM "state of charge" lights. The Trimetric monitor is excellent (and I'm sure there are a few others but I have no experience with them). In the mean time, when in full sun, what happens when you turn on a high load? If the amps from the panels increase, you are likely at a full battery SOC and the charge controller is simply throttling the amount of amps passing thru to the batteries.

[rcjunkie]

When I installed four 100 watt renogy panels, only 2 panels worked. Why was that? Because 2 of the 4 inline fuses I bought had no fuses inside them and the circuit was open.

Please check your fuses for continuity.

[Almot]

The panel inside the coach is still on yellow on battery state of charge.

OEM battery status panel is as useful as Christmas lights.

It is possible that your battery have gone full cycle Bulk-Absorption-Float, and now is floating at 13.7 as it should.

That's why I prefer having a controller that gives me full report in the evening - was Absorption point reached or not, while I was away.
Get $30 AH-meter.

[1492]

Moved from Forum Technical Support

[bcbob]

I ran the batteries down to 12.4 a few days ago on inverted power. The panel inside the coach is still on yellow on battery state of charge. Seems weird to me, but I am an absolute novice on this stuff and am trying to get educated. It's my dinner time. Thanks to all. More tomorrow.

[KD4UPL]

If the batteries are full enough to kick the charge controller in to the absorbsion stage then the amps will be lower. A charge controller doesn't just run wide open all the time. It "controls" the charge to not overcharge the batteries.
If the charge controller is still in bulk then you may have some dirt on the panels.

[bcbob]

yes, I have cleaned them.
The battery bank shows 13.7 volts.

[jake2250]

Yeah,, physically go up and check the panels,, we were camping for a week and the first three days I was doing great (two 100 watt panels) 9.5 amps, then it dropped in half after we had a little rain one night,, threw the ladder and had two good size leaves that blew off a tree and got pasted on the panels.
A good wipe down and I was back to 9+ amps and I was happy!!

[pianotuna]

What is the state of charge of the battery bank?

[bcbob]

13.7 volts.
Four 6 volt EXIDE batteries.

[time2roll]

What is the battery voltage at 2-4 amps?