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Charge Controllers and Clippers => The "Classic" charge controller => Topic started by: CayoPV on March 21, 2021, 04:35:13 PM

Title: Classic 150 - PV Voltage Incorrect - Refuses to Bulk/Charge
Post by: CayoPV on March 21, 2021, 04:35:13 PM
So I have an installation with a Classic 150 that the PV Voltage is reading an average of 24V higher than it should. It's also not wanting to bulk. It just clicks for a few seconds in an attempt to bulk, switches to rest for a bit, then attempts the process again. Endlessly looping.

The VOC I read with the Fluke is around 115V. The Midnite reads 139V. All connections are tight and properly sized. It's not a resistance/poor connection issue as far as I can tell.

The system was working fine. Or so I thought (client installation). Checked the logs and it's only charged every other day. What's with that? The log shows some days 9.7-11VPC max for an entire day. 0 kWh.

The following or preceding day it's showing ~139VPC and charged perfectly fine.

It's not working today but based on the log pattern, it should work tomorrow fine.

Any thoughts?
Title: Re: Classic 150 - PV Voltage Incorrect - Refuses to Bulk/Charge
Post by: boB on March 21, 2021, 06:17:00 PM

Uh Oh.  Doesn't sound good.

There is a voltage offset adjustment in the Classic BUT  this amount of difference has to be something else wrong with it I would guess.

Bad resistor in a voltage divider maybe ?

If it were a voltage reference issue, then I would think that the battery voltage would also be off some.

Is the battery voltage reading more or less correct ?

If it is broken, then our support people can take care of you.

Sorry this has happened !
Title: Re: Classic 150 - PV Voltage Incorrect - Refuses to Bulk/Charge
Post by: ClassicCrazy on March 21, 2021, 11:03:34 PM
If it is charging every other day - maybe the Skip Days setting is set ?

Larry
Title: Re: Classic 150 - PV Voltage Incorrect - Refuses to Bulk/Charge
Post by: boB on March 22, 2021, 09:49:29 PM
Quote from: ClassicCrazy on March 21, 2021, 11:03:34 PM
If it is charging every other day - maybe the Skip Days setting is set ?

Larry


That's a great thought, Larry....

But even on skip days, it should at least float.