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Charge Controllers and Clippers => The "Classic" charge controller => Topic started by: Lya72 on November 02, 2012, 10:13:17 AM

Title: Classic PV Negative wiring
Post by: Lya72 on November 02, 2012, 10:13:17 AM
Hi all,

Do you connect the PV negative cable to the Classic DC terminal Connector ??

In the manual on pages 21 and 22, there is no connection on the Classic PV Negative connector.

I'm interested in the answer because my Classic is showing at night a PV In voltage of 9 volts to 13.4 volts. You can say that is from the moon !
But when I switched off the PV breaker connected on the PV positive wire, also at night, the MNGP continue to show a PV In voltage, growing to more than 14.4 Volts.

Is this normal ?

Thanks to all.

Yann
Title: Re: Classic PV Negative wiring
Post by: Halfcrazy on November 02, 2012, 12:04:27 PM
The Classic has common negatives and this basically means all PV and DC negatives can be combined at a buss bar and a single negative run to there classic.

The Input voltage is there because there is a small bleed resistor internally the classic uses to tell when it is ok to turn on in the AM. You will typically see any where up to say 75% of the battery voltage.

Ryan
Title: Re: Classic PV Negative wiring
Post by: TomW on November 02, 2012, 12:54:27 PM
Thanks, Ryan, I was about to ask the same question on why the input voltage. I was pretty sure my panels were not making any volts @ nite  ;D.

Tom
Title: Re: Classic PV Negative wiring
Post by: Lya72 on November 02, 2012, 02:40:38 PM
Thanks Ryan.

The first answer was in page 21 of the manual !!   Sorry. I should have RTFM, more than once.

But for the second part, it should enter in the manual, because it's surprising for the newbies.

Yann