A Forum run by Enthusiasts of MidNite Solar

Charge Controllers and Clippers => The "Classic" charge controller => Topic started by: Corndog on August 10, 2025, 04:11:46 PM

Title: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: Corndog on August 10, 2025, 04:11:46 PM
Is it possible for the classic to read higher voltages suddenly but different from the Mate3 due to a bad battery bank or should the mate be reading the same if this was the case ?

Bank voltage on the classic will read 48.7 then suddenly go into absorb reading 59 then float 54 but the mate still reading 48-49-50 . We have a second classic 150 brand new and installed that problem was solved for two weeks but now it is doing the same. Battery voltage measured at the classic terminals is reading what the classic is displaying, 59 or 54 when this occurs.

Battery bank 48v is 8 years old, off grid full time home batteries cycle daily.

I hope this makes sense,

Here is our system.
Off Grid
2 x Outback Flexware- VFX3648 Inverter
Mate 3
Power Hub 10
Hanwha solar panel 345 watts-- total array 5520 watts
Midnite CI150 Charge
13 KW Diesel Gen
Batteries- Surrette 550 6V x 16

Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: Corndog on August 11, 2025, 11:26:12 AM
I should have included, bad battery/s end amps the cause, would that make sense ?
Last month specific gravities were ok, will do a full charge gennie tonight and check SP Grav again in the morning.
Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: ClassicCrazy on August 11, 2025, 06:22:19 PM
did you check all your connections along the way - like on breakers , etc ?
Larry
Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: ClassicCrazy on August 12, 2025, 10:08:39 PM
Read through this and see if any of the symptoms match what you see.
https://midniteftp.com/forum/index.php?topic=5987.msg54525#msg54525
Larry
Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: Corndog on August 18, 2025, 11:08:35 AM
Thank you Larry,
We believe it is one of the breakers between the batteries and the classic or the array. Two new ones are ordered and awaiting delivery.I will update soon.
1.PNL-60-AC/DC
2.PNL-80-DC
Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: Corndog on August 30, 2025, 05:19:08 PM
Problem solved, loose connection between negative terminal bus bar and the shunt (outback panel).Im guessing 8 years of hot cold changes can cause this.  Thank you for your help Larry
Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: ClassicCrazy on August 30, 2025, 07:48:26 PM
weird how those things come loose.  That is one of the first thing electricians always check in AC panels to see if all the screws on breakers and stuff are tight .

Larry 
Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: Corndog on August 31, 2025, 08:31:54 AM
Yes he went through everything, found other loosening connections as well. Lesson learned.
With winter coming (northern Ontario here) I will sleep well knowing that has been looked over.

Can I ask for some help on my end amps setting here or start a new thread ? We have a new battery bank coming 16 x S6 L16-HC 445 AH Rolls (48v)  with a slightly higher AH at 20c than our current S6 L16 390 AH (48v) set up.
Title: Re: Classic 150 Voltage reading different than Mate3 battery voltage
Post by: Vic on August 31, 2025, 01:45:25 PM
Quote from: Corndog on August 31, 2025, 08:31:54 AMCan I ask for some help on my end amps setting here or start a new thread ? We have a new battery bank coming 16 x S6 L16-HC 445 AH Rolls (48v)  with a slightly higher AH at 20c than our current S6 L16 390 AH (48v) set up.

Yes,   please DD start a new Post for the EA settings,  glad that you found that loose connection.

Vic