Solar charge controller and fully charged batteries?

[VicS]

What does the forum think of 0.06 Amps from a 50w panel?

Assuming you did have the meter set to read DC
Viewed together with your voltage readings that your solar system is not performing as it should.

I think I would start by measuring the open circuit volts and short circuit current of the panel and comparing these with the figures in the tech spec

If these look about right (after allowing for the fact that the panel is flat rather than angled towards the sun ) I think I would then check the panel and controller output volts and current while connected to just one significantly discharged battery. The aim being to check the performance of the controller whie it should be delivering its maximum output without sharing between two batteries.

 

[Alex_Blackwood]

Thanks for all the replies. Alex, I couldn't get your link to work but the symbols on the meter are the same for 40 and 400 A, ie a straight line above a squigly one. And VicS has the correct page in the manual so that looks good news for DC. But his question about if a PWM controller's pulsed output confuses the meter? And thanks Noelex, I was only measuring a single wire, trying to hold it steady in the centre of the clamp space (equidistant from the arms.) As for the L.i.B banana plugs method, for me that sort of (re)wiring is only something I would contemplate if I wasn't getting by, as we are on a swinging mooring. I'd see that as a winter job. What does the forum think of 0.06 Amps from a 50w panel?

My mistake!!

 

[FairweatherDave]

Thanks VicS. (I did have the meter set to DC when reading the current btw).
However not being particularly confident in the electrics department I have had to take time to understand what you have written and if I have it correct it makes good sense.
You wrote "I think I would start by measuring the open circuit volts and short circuit current of the panel and comparing these with the figures in the tech spec".
I interpret that as disconnect the panel from the controller and measure the volts and current of the panel in sunshine and comparing with the tech spec. And then connect up everything to one battery needing charging (not at float level) and measure volts and current either side of the controller. Apologies for needing it spelt out but if in doubt ask

 

[VicS]

Thanks VicS. (I did have the meter set to DC when reading the current btw).
However not being particularly confident in the electrics department I have had to take time to understand what you have written and if I have it correct it makes good sense.
You wrote "I think I would start by measuring the open circuit volts and short circuit current of the panel and comparing these with the figures in the tech spec".
I interpret that as disconnect the panel from the controller and measure the volts and current of the panel in sunshine and comparing with the tech spec. And then connect up everything to one battery needing charging (not at float level) and measure volts and current either side of the controller. Apologies for needing it spelt out but if in doubt ask

You have the idea.
Measuring the open circuit volts ( V_max ) and the short circuit current ( I_max ) should tell if the panel is Ok. Expect somewhat over 20 volts and a little less than 3 amps

Connecting just one battery in need of charging should eliminate any effects of the controller modulating the output or sharing the output between two batteries.

 

[FairweatherDave]

Thanks again VicS. You've got me started!
I have found a couple of good youtubes with your pointers in #42

Brilliant forum! Wish these things were more instinctive but I'm getting there
Impatient to get to the boat and check things out.