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General Category => General Discussion => Topic started by: littleharbor2 on November 16, 2021, 08:33:16 AM

Title: Voltage sense adjustment.
Post by: littleharbor2 on November 16, 2021, 08:33:16 AM
 I am building a Lifepo4 battery bank and know how sensitive these batteries are to over voltage (found out the hard way)
My question is how do I adjust the battery voltage sensing on the Classic? Now it reads about .2 volts lower than the actual battery voltage, checked with my Fluke meter. The voltage reading on my Trace Sw4024 and Bogart Trimetric is correct but they aren't the ones doing the charging.
I'm confident that connections are tight but will verify today. The distance between CC and batteries is only about 3 feet.
Title: Re: Voltage sense adjustment.
Post by: Steve_S on November 16, 2021, 10:29:06 AM
TWEAKS Menu, Offset VBatt is where to set the voltage offset difference.

BUT, the differential should be tested in 2 ways...  1st, while the system is pulling a "normal" (the usual common load) so that you know what the difference will be during Discharge.  Then again when Charging is ongoing (with normal loads, as above).

For the Classic, you are interested in the difference value during charge.  The classic cares nothing about discharge issues.  The Inverter though is where the Differential during Discharge really counts as you want to be certain you do not reach the BMS LVD Cutoff.  It is always best to prempt having the BMS forcing a cutoff due to conditions.
Title: Re: Voltage sense adjustment.
Post by: littleharbor2 on November 16, 2021, 08:17:35 PM
Great info! Thanks Steve