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Balmar SG200 battery monitor

Jan 25, 2011
2,223
S2 11.0A Anacortes, WA
Anyone know how this monitor handles a bank and a separate start battery with an ACR In between?
 
Feb 26, 2004
21,950
Catalina 34 224 Maple Bay, BC, Canada
Mark, they generally don't do "measurements" when charging, which is when the ACR connects the two banks. Once charging stops, the ACR opens and separates the two banks and the SG works just fine on the house bank.
 
Dec 28, 2015
1,357
Laser, Hunter H30 Cherubini Tacoma
That is what it is designed for, multiple banks require a shunt for each bank. A single shunt will monitor two aux batteries but will only give the voltage for them, not any of the other functions. No issue with a ACR .
 
Jan 25, 2011
2,223
S2 11.0A Anacortes, WA
The ACR doesn’t open when charging stops. It opens when the battery voltage drops to a predetermined level. So, there is some time (depending on loads)that the monitor is reading both the bank and the start battery. Then the start battery drops out When that voltage is reached..
 
May 17, 2004
3,469
Beneteau Oceanis 37 LE Havre de Grace
The Blue Seas ACR will open when the bank hits 12.35 for 10 seconds or 12.75 for 30 seconds. It won’t take much load to pull off the surface charge and hit those thresholds. Probably happens within a couple minutes of even a light load, which is a small fraction of amp hours and very small percentage of State of Charge.
 

CarlN

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Jan 4, 2009
577
Ketch 55 Bristol, RI
Because the shunt is only attached to the house bank negative side it only measures amps going into and out of the house bank. Amps going into or out of the start bank because of an ACR doesn't effect its calculations (although it will measure voltage of the start bank). If you want to have a state of charge for the start bank you need a 2nd shunt.
 
Feb 6, 1998
11,436
Canadian Sailcraft 36T Casco Bay, ME
Because the shunt is only attached to the house bank negative side it only measures amps going into and out of the house bank. Amps going into or out of the start bank because of an ACR doesn't effect its calculations (although it will measure voltage of the start bank). If you want to have a state of charge for the start bank you need a 2nd shunt.
Bingo!