Puzzled about solar panel voltage and regulator

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mattonthesea

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Ihave connected a 30w solar panel up to an old Rutland 200 regulator (solar connection point). when I tested the voltage from the panel it was 20v (bright sunny day) but when I tested it connected to the regulator it was 1.5v. The battery was about 90% charged.

I tried using a small amount of current (nav lights) and the battery manager thing said that I was using current. I then tried disconnecting the solar panel to see if the use of current changed. I assumed that the time to total discharge would be affected - is this right? But the time stayed the same even after a few minutes.

There was a puff of wind for a mo and the wind gen went round and the numbers changed briefly.

I connected the shore power back up and the time to discharge became time to charge.

New regulator perhaps? Or is there a way I can check it?
 
mattonthesea said:
Ihave connected a 30w solar panel up to an old Rutland 200 regulator (solar connection point). when I tested the voltage from the panel it was 20v (bright sunny day) but when I tested it connected to the regulator it was 1.5v. The battery was about 90% charged.

I tried using a small amount of current (nav lights) and the battery manager thing said that I was using current. I then tried disconnecting the solar panel to see if the use of current changed. I assumed that the time to total discharge would be affected - is this right? But the time stayed the same even after a few minutes.

There was a puff of wind for a mo and the wind gen went round and the numbers changed briefly.

I connected the shore power back up and the time to discharge became time to charge.

New regulator perhaps? Or is there a way I can check it?
Click to expand...

It is a shunt type regulator. Perhaps the 1.5 volt reading was this low because the regulator was dumping the solar panel output. A reading of the current flow from the solar panel would confirm or other wise.

The proof of the system will be if it charges a partly discharged battery from both solar and wind gen

I would partly discharge the battery , restrain the wind gen and measure the charging current with the solar panel as the only charging source.

then I would try to do the same for the wind gen while the solar panel is covered.

Prhaps initially in both cases keep a significant load on the battery to absorb the solar or wind gen output, then disconnect the load and watch to see if the battery recharges.
 
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I think first thing to do is check the solar panel alone. Check 20v with no load or other connection to the panel.
Then connect directly to the battery via an amp meter. In lots of sun you should get around 1.5 amps or perhaps a bit less. ie 1 amp is good. Or you can connect an amp meter directly across the output of the solar panel with no other connections and again get about 1.5 amps. If all Ok then you can try to get it all working with the wind gen regulator. Or buy a cheap pulse width reg on line. olewill
 
I agree with William, test the panel first.

You alredy checked the opencircuit volts and found 20V

Now while the panel is again disconnected from the controller connect your multimeter, on its highest current range (10 amps??), directly to the panel to measure the short circuit current.
 
today I tested the solar panel connected only to the ammeter and got 0.1 amps but it was cloudy so not sure if this was a good time to do it.

I have an MPPT charge controller which I am planning to connect the panels (1x80 (yet to be fitted) and 1x30) to the batteries and leave this old Rutland 200 to work just with the wind gen. Does that sound like a sensible idea?
 
mattonthesea said:
today I tested the solar panel connected only to the ammeter and got 0.1 amps but it was cloudy so not sure if this was a good time to do it.

I have an MPPT charge controller which I am planning to connect the panels (1x80 (yet to be fitted) and 1x30) to the batteries and leave this old Rutland 200 to work just with the wind gen. Does that sound like a sensible idea?
Click to expand...

Being of different powers the solar panels will have to be connected in parallel. hopefully they have similar characteristics esp VPMax
 
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