Strange Readings from a Solar Panel

[ribbony]

I repaired a Solarex 60 watt panel this week, one of the wires had corroded off the silver bus strips in the end of the panel. The operation to repair it was successful.

However, I had bought a new regulator (10A MPPT unit off eBay) as at first I though the regulator was faulty, so replaced it then found the corroded wire.

The display ont he regulator/controller shows all sorts of things, the point of interest is that the panel appears to only be outputting up to and no more than 18watts on the clear days with the sun directly above the panel. Seen it is a 60watt panel, is this normal ?

The amps range up to about 1.6 is the highest I have noticed so far, that also seems low ?

[noelex 77]

Yes the output should be more than that.

Given your repairs there is probably still a bad connection in the panel, but there is always the chance of a faulty controller. The cheap MPPT controlers are very unreliable.

Try a direct connection of the solar panel to the batteries. The current can be measured with a multimeter, (or even better a clamp on multimeter). You won't do any harm overchaging the batteries providing the battery is little discharged, or there is a load of a few amps. (remove the fuse, or cover the solar panel while making the connections, if you are connecting directly to the battery teminals. It is not the place where you want a spark)


It would also be worth measuring the panels Voc and Isc. These measurments can be done with a multimeter.

[Samantha ann]

I have been gifted a solar panel of in known age and have some questions. First size is 24x 60. Is working Green light blinking. See pics attached. Any way to figure out amp out put ? Can I hung direct to house bank? ( 4 6volt appox 550 ah)

[noelex 77]

Originally Posted by Samantha ann

I have been gifted a solar panel of in known age and have some questions. First size is 24x 60. Is working Green light blinking. See pics attached. Any way to figure out amp out put ? Can I hung direct to house bank? ( 4 6volt appox 550 ah)

A modern solar panel that size would be about 130w, but the older poly panels were less efficient, so its probably about 100w. Not bad for free
Rigid panels don't deteriorate much so if its not damaged it should be putting out close to that still.

100w is too big to connect to the battery without a regulator, but the reference to the "green light blinking" makes me think there is a regulator built in, or included.

You can use a multimeter to measure the output.

The safest, simplest measurements are Voc. ( put the multimeter on 40v and measure the panel when its not connected to the battery, or regulator. It should read about 20-21v in full sun. Next connect it to a flattish battery with the multimeter in series, measuring current. In full sun it should be putting out 3-5A.

[Teknav]

Voltage measurement = parallel connection with your Digital Multi Meter (DMM); as if connecting each lead to each battery terminal, respecting polarity. (Black Ground is the < ->, while Red Hot is the < + >. Black to Black and Red to Red. Your DMM should be on the DC Volt selector and output Voltage jack. Current Measurement = series connection with your DMM. The leads of the DMM must be "inside the circuit/part of the circuit" to measure the flow; if not done properly, you can damage the DMM or blow its fuse. The meter should be set on AMP (your red lead must be connected to AMP, NOT on the Voltage output jack). A final thought...It is the current (AMP) that KILLS people; exercise extreme caution when taking measurements! If you've never used a DMM before, let someone show you how to safely use one. (Never ever measure the voltage or the current to fallen power lines after a storm; you and your DMM can get FRIED in an instant!) Mauritz