Reading AMPS from a solar panel
I have a 12v - 120W solar panel on my TC. This is controlled by a Morningstar Sunsaver 20 into a single group 27 wet cell battery. I have a Trimetric 2025RV battery monitor installed. As far as ...
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You want your Isc to see if that is reaching the batts, but you can't get Isc while the panel is connected, so all that shunt work won't help there.
You can use the extra shunt and meter to get amps between controller and battery. This is what you want to compare with the Isc figure if you think something is wrong with your amps to battery being too low.
Don't forget that the amps will drop from batt voltage being high for two reasons;
-battery amps acceptance rate falls at high SOC
-panel Isc drops with high batt voltage per IV curves for your panel.
Next you can have your solar -only amps separate from the Trimetric net amps readings, where you have to mentally derive how much of that is solar. (I do that. It is no trouble really, once you know what is normal amps without the solar)
To get the solar included in the Trimetric , the neg from the controller to battery has to go across the Trimetric's shunt , same as the other items you have the Trimetric reading. Don't forget to turn off the Trimetric's auto AH reset if you have solar on there (see Trimetric instructions on that)
Panel current is Isc and you need to be disconnected from the controller to get that by just putting your meter across the panel's pos and neg. You cannot get voltage at the same time of course. You can get that by switching your meter over to voltage with it connected across the panel wires the same way. Watch out you don't fry your 10a mulitmeter if your panel short circuit current will be over 10a.
You can use the extra shunt and meter to get amps between controller and battery. This is what you want to compare with the Isc figure if you think something is wrong with your amps to battery being too low.
Don't forget that the amps will drop from batt voltage being high for two reasons;
-battery amps acceptance rate falls at high SOC
-panel Isc drops with high batt voltage per IV curves for your panel.
Next you can have your solar -only amps separate from the Trimetric net amps readings, where you have to mentally derive how much of that is solar. (I do that. It is no trouble really, once you know what is normal amps without the solar)
To get the solar included in the Trimetric , the neg from the controller to battery has to go across the Trimetric's shunt , same as the other items you have the Trimetric reading. Don't forget to turn off the Trimetric's auto AH reset if you have solar on there (see Trimetric instructions on that)
Panel current is Isc and you need to be disconnected from the controller to get that by just putting your meter across the panel's pos and neg. You cannot get voltage at the same time of course. You can get that by switching your meter over to voltage with it connected across the panel wires the same way. Watch out you don't fry your 10a mulitmeter if your panel short circuit current will be over 10a.
