Balmar Smart Gauge question - Maine Sail?

[Chris & Lenore]

From all that I've read, this appears to be an excellent product but I'm curious how it works with a start battery connected to the house bank with a ACR?

During charge, the start is essentially paralleled with the house. If the unit samples voltages during charge, would this not affect things i.e. knowing when the house bank is at 100% (I realize it only provides voltage of the start battery, not SOC)

Or does it use discharge voltages for most of it's calculations? In that case, the start battery would not be combined with the house while discharging.

Still, I'm not sure how it would know SOC of the house battery while it's being charged and when the start battery is "combined" via the ACR.

Probably it works fine as many installations would be using an ACR to keep a start battery charged i.e. I'm probably "over thinking" but hey, it's -14 F here today and I've got nothing else to do....

Chris

 

[Chris & Lenore]

I just read the installation/operation guide for the product and it answered my question.
The SOC during charge is not "measured" but a "timed" function. The Smart Gauge will give an accurate SOC once discharge begins. So it could be that it shows 100% when charging but the battery really isn't at 100%. Once off charge, it will show true SOC.

I could only see this as an issue with solar charging - you wouldn't really know the SOC until the sun went down (or you switched the panel off for a few minutes).

Chris

 

[dparilla]

I am installing a SmartGauge on my "test" boat this week. I will post my feedback after that. Based on Maine Sail's recommendations, the SmartGauge is a worthwhile tool for those interested in the best care and feeding of their batteries.

More to follow.
Monkey

 

[Maine Sail]

From all that I've read, this appears to be an excellent product but I'm curious how it works with a start battery connected to the house bank with a ACR?

During charge, the start is essentially paralleled with the house. If the unit samples voltages during charge, would this not affect things i.e. knowing when the house bank is at 100% (I realize it only provides voltage of the start battery, not SOC)

Or does it use discharge voltages for most of it's calculations? In that case, the start battery would not be combined with the house while discharging.

Still, I'm not sure how it would know SOC of the house battery while it's being charged and when the start battery is "combined" via the ACR.

Probably it works fine as many installations would be using an ACR to keep a start battery charged i.e. I'm probably "over thinking" but hey, it's -14 F here today and I've got nothing else to do....

Chris

The Smart Gauge will not be as accurate during charging but I've not usually seen it off by more than 10%. This is still far better than how 99% of the Ah counters out there are set up.... The nice thing about the Smart Gauge is that you really only need to check it once or twice per day and then address what you need to do. Once before bed, and once in the early morning before the sun hits solar.... As it learns your bank it will get more accurate, even during charging times. The ACR is a non issue as it will only be connected during charging and the SG is designed to hone in on SOC best in discharge mode...

 

[Chris & Lenore]

Thanks for the reply Maine.

I definitely agree it's a better solution. I have friends suggesting the Blue Sea monitor - it provides battery, tank, AC and bilge cycling info. But, the main item I want it for is battery management and it's just a basic "coulomb counter" for that.

I spoke with a representative at Blue Sea and they are working on a new product without the SOC function (and handles more tank monitors). He mentioned that the Balmar product was one of the reasons....

So I guess I'd better order the Balmar.

Chris

 

[Bill Roosa]

SOC with amp and volt meters only

You folks do know that you can measure the SOC by knowing the amps flowing in/out and battery voltage right? You do NOT have to wait for 3 hours with no amps flowing to use voltage to know the battery SOC
Google and being able to read are handy tools

 

[Bill Roosa]

C/x values are battery AH capacity / amps (in/out) so
if you have a 400 AH bank....
C/5 = 400/5=80 amps
C/10 = 400/10 = 40 amps

 

[Maine Sail]

C/x values are battery AH capacity / amps (in/out) so
if you have a 400 AH bank....
C/5 = 400/5=80 amps
C/10 = 400/10 = 40 amps

And you do track the changes with age in your spread sheet at varying loads........? Because it changes and loaded voltage does not remain stable. You would need to re-test for this regularly. It is funny because I was recently discussing this exact scenario with the chief engineer at Lifeline battery for some testing I am conducting for one of the sailing publications which involves Lifeline batteries..... Lifeline is one of the few who publish loaded voltages but they don't remain accurate for very long and would need to be re-calculated..