Balmar SG-200 Battery Monitor

[rgleason]

Sorry it was I who did not know Smartgauge "Data Cell II" had a shunt. It might have been helpful to leave a link to that device as merlin is somewhat elusive.
Peace.

[CatNewBee]

Every battery monitor can precisely measure DOD as Ah used measuring current and time and adding them up, this is a no-brainer, it is harder to estimate Ah left or time left or remaining capacity, simply because it varies depending on temperature, age, chemistry, internal resistance, geometry of the plates and load. Additionally PSOC and charge efficiency and Peukert factor guessing make it even worse.

You can tweak the parameters to get close to, but you need some recalibration points / sync. The good news is, with FLA you want the battery charged full as often as possible and avoid deep discharges for a long life, so you likely will hit the sync point quite often, and your gadget will be accurate most of the time.

[john61ct]

Originally Posted by rgleason

Sorry it was I who did not know Smartgauge "Data Cell II" had a shunt. It might have been helpful to leave a link to that device as merlin is somewhat elusive.
Peace.

aargh, the Merlin DataCell II **does** have a shunt. Apparently its designed functionality is similar to Balmar's SG200,

combines the "SmartGauge style" calculating methods we're calling "Active Impedence Compensation"

with coulomb-counting based methods,

also giving a SoH reading in addition to SoC,

but targeted to government / military customers.


And Merlin DataCell II is a completely different product from their original SmartGauge invented by Gibbo,

which has no shunt, does no coulomb-counting.

I hope this helps avoid further confusion.

[john61ct]

Originally Posted by CatNewBee

Every battery monitor can precisely measure DOD as Ah used measuring current and time and adding them up, this is a no-brainer, it is harder to estimate Ah left

Nit picky I know, but want to point out that actually, these are precisely the same data point. AH withdrawn as an absolute number may well be perfectly counted,

but DoD and SoC are just inverse percentages, not independent of each other, and always relative to current AH capacity, which has usually been "the great unknown" except for those very few regularly doing load testing.

And thus, plus all the other reasons you mention, always approximate measures.

Some SoC meters' guesstimates more accurate than others' is the best that can be said.

Very regularly resetting when getting to 100% as verified by trailing amps is as you say the key with the AH-counting methodology.

Not so necessary with the devices using Active Impedance Compensation techniques.

AIC

[CatNewBee]

Seems Balmar has gone back to the classic route of Coulomb counting using a shunt instead of guessing SOC based on voltage changes only (evolution from smart gauge to SG200) and focusing more on fancy graphic displays, networking and the App development.

So I would say, it becomes now comparable with all the Xantrex, Victron, MasterVolt etc. battery monitors.

SG200 Battery Monitor | Balmar

[rgleason]

Originally Posted by CatNewBee

So I would say, it becomes now comparable with all the Xantrex, Victron, MasterVolt etc. battery monitors.

SG200 Battery Monitor | Balmar

CNB I am not so sure of that. I believe there is more going on than that, including calcs based on both coulomb counting and more instantaneous conditions and then comparisons/use of known chemistry characteristics, etc. but Chris W. would be the one to reply I guess.


I find it interesting that after a full charge of my batteries to 100% SOC and 100% SOH about 24 hours later, the SOC has dropped to 91% and also waiting 4-5 days after a full charge the SOC shows as 85%. I need to do some more complete draw downs and testing, but want to do it more accurately.

[john61ct]

Balmar had nothing to do with the design of the SmartGauge.

Is as far as we know still the most accurate SoC meter for a wide range of lead banks,

far more is computed 20,000 times per second than just straight voltage.

But it has never worked with LFP, never was intended to.

[sailinglegend]

Originally Posted by john61ct

....But it has never worked with LFP, never was intended to.

Smartgauge never worked with LPF because Gibbo never did the programming for it because Merlin's does not recommend LPF to any of its clients.

[rgleason]

Optional Smartphone/Bluetooth® Gateway (Coming Soon)

• Free iOS and Android Apps (Requires Bluetooth® Gateway PN SG2-0300)
• Gateway is not yet available for purchase but is coming soon.
• View All Parameters on your Phone
• Download Product Updates

https://shop.pkys.com/Balmar-SG200-b...or_p_7850.html


The Balmar SG200 has configuration settings for LiFePo4 and all the other normal battery types FLA, AGM, GEL, LiFePo4, just to be clear about it.

[rgleason]

Its really easy, if you watch carefully.

Installing Deutsch -style connectors

There is one of these connectors to install.

[ayates]

Does anyone have an SG-200 shunt? If so, could you tell me the distance between the two mounting holes?




Thanks,


Allan.

[john61ct]

PM Chris, user witzgall here, or email or call them

[witzgall]

Allen,

There are actually six mounting holes on the Smartshunt. The two on each end near the cable bolts are about 4.1 inches apart. Does this help?

Chris

Originally Posted by ayates

Does anyone have an SG-200 shunt? If so, could you tell me the distance between the two mounting holes?




Thanks,


Allan.

[ayates]

Thanks a lot! That is just what I needed. I am having a mounting panel made up (before I receive the SG-200) for both the SG shunt, a Victron shunt, and a couple of battery fuses.




Allan.

[lateral]

Whats the latest on SOH accuracy?
Are the units performing as specified by Balmar?