Balmar SG-200 Battery Monitor

[Prospective]

Originally Posted by steve77

Try again to contact Balmar tech support. I had a similar issue - SOC was at 100% while (in my case) still bulk charging. The voltage displayed was also higher than actual, as I confirmed with a DVM and the other two devices permanently installed aboard that display battery voltage. Check your voltage reading on the SG200 and use a DVM or some other means to confirm it is accurate.

In may case, this happened after I upgraded to the latest software, version 2.91. Soon, my SG200 started to display battery current as -1300 Amps. Pretty sure that wasn't correct.

I contacted Balmar and they recognized the issue and were working on it. They sent me a version to test, but it is still not properly calculating SOC and now displays -0.0 (using the App) for battery current.

The upshot is that, unlike many of the posters here, my experience with the SG200 has not been successful. I'm not going to beat up on Balmar because I like their products, they have been responsive to me, and are currently working to release software fixes to address issues that arise. I'm confident that at some point I will have a working unit that will accurately display my battery parameters.

Cheers!

Steve

Thanks. My voltage readings appear correct when checked against other volt meters on board. In fact, that's how I know somethings up with the SOC. Voltage is way too low for stated SOC.

I got a response back from Chris at Balmar. But it didn't seem to really address my issues. I sent a follow-up email and didn't hear back. But in the meantime, at his recommendation, I reset the bank capacity and battery type. So, obviously now it's "relearning". I've only had two charge/discharge cycles so far but I've got 4 days on a mooring coming up so it will have a chance for several more.

Right now I am not super pleased with this device. One enhancement would be to have an amp counter that did a traditional measure of net amps in/out so we'd have something to compare our SOC readings to. I'll give it some time. But I hope this thing gets sorted out.

[steve77]

Originally Posted by Prospective

Right now I am not super pleased with this device. One enhancement would be to have an amp counter that did a traditional measure of net amps in/out so we'd have something to compare our SOC readings to. I'll give it some time. But I hope this thing gets sorted out.

The unit does display Amps in/out (negative values are for Amps out). If your shunt is wired correctly it should display properly. Do you mean Amp-hours? It doesn't display those.

Cheers!

Steve

[witzgall]

In the manual, it suggests NOT changing the taper current or charge voltage from the ones that are created from the battery profile. I suggest you do a factory reset and let it do it's thing. Then, if you have issues, adjust them slowly using the guidance in the manual.

I suspect that you are seeing "charge termination" set too early as the charger voltage is too low. This is not the voltage the charger is set to, but rather what the voltage is when the battery is full. Actually, the voltage seen has to be a bit higher than the set value, and at the same time the current has to be below the value set.

Originally Posted by JensLB

Hi,

I installed a sg 200 for a couple of weeks ago. Have a bank of 280 Ah AGM. I choosed taper current to 3A and max charge voltage to 14,4V. I did a discharge down to ~50% and thought it will learn during my vacation on the boat since I didn’t have time for more.

Now that I’m on vacation my question is that 100%+ SoC appears way too early.
We have had really nice weather and I have a 165W solar panel that keeps the bank pretty full, but has never produced the voltage to trigger the 100%+ values I have entered. We have two refrigerators running on full steam most of the time, should be roughly equal to the solar panel output. Charging all kinds of electronics. During daytime we go from a few amps draw to a couple of amps charge depending on what’s on for the moment.

In the morning we have about 94% SoC and about 12.5V, after an hour in the sun it shows 100%+and 13V, but it never went over 13,2V.

SoH shows everything between 89% - 100%, since the bank is farly old I would actually be impressed if even 89% is correct.

I feel like the solar panel tricks it in some way and makes it show higher SoC than what’s true.

If someone has a theoryor knowledge, please explain this to me

//Jens

[witzgall]

Amp hour counting is coming! We have heard this loud and clear from many users. Right now we are working on another set of app features (TBA) and once they are done, AH counting is next.

Chris

Originally Posted by steve77

The unit does display Amps in/out (negative values are for Amps out). If your shunt is wired correctly it should display properly. Do you mean Amp-hours? It doesn't display those.

Cheers!

Steve

[Prospective]

Originally Posted by steve77

The unit does display Amps in/out (negative values are for Amps out). If your shunt is wired correctly it should display properly. Do you mean Amp-hours? It doesn't display those.

Cheers!

Steve

Thanks, yes I meant amp hours. Nice to hear it's coming.

[JensLB]

Originally Posted by witzgall

Actually, the voltage seen has to be a bit higher than the set value, and at the same time the current has to be below the value set.

Thanks for your respond.
I don’t feel that the part of your answer I quoted correlates to the figures I get from the sg200. If I have set the max charge voltage on the sg200 to 14.4V and it never reach it, in my world the sg200 shouldn’t say 100%+ SoC since that criteria isn’t fulfilled.

I have monitored the voltage during the day and it has never gone above 13,3V, still I get 100%+ SoC. I understand that you say I shouldn’t mess with the factory settings but since the factory settings have even lower voltage threshold than my chosen 14.4V, I felt it was needed as the manual actually says.

//Jens

[witzgall]

There are a few things here to check.
1. Installation - make 100% sure that there are no negative wires from sources or loads connected to the batteries directly.
2. The voltage/power lead for the SG200 IS connected to the battery directly, not on a bus bar away from the batteries.

Can you check these two items?

Also, SoC can reach 100% without charge termination taking place, if the amps that poss through take the SoC from XX% to 100%. IE if you are at 90% and add ten amp hours, to a 100AH battery, it will go to 100%. This may not be your issue, but I want to state it to clarify.

Chris

Originally Posted by JensLB

Thanks for your respond.
I don’t feel that the part of your answer I quoted correlates to the figures I get from the sg200. If I have set the max charge voltage on the sg200 to 14.4V and it never reach it, in my world the sg200 shouldn’t say 100%+ SoC since that criteria isn’t fulfilled.

I have monitored the voltage during the day and it has never gone above 13,3V, still I get 100%+ SoC. I understand that you say I shouldn’t mess with the factory settings but since the factory settings have even lower voltage threshold than my chosen 14.4V, I felt it was needed as the manual actually says.

//Jens

[JensLB]

Originally Posted by witzgall

There are a few things here to check.
1. Installation - make 100% sure that there are no negative wires from sources or loads connected to the batteries directly.
2. The voltage/power lead for the SG200 IS connected to the battery directly, not on a bus bar away from the batteries.

Can you check these two items?
Chris

I’m positive on both. Reconnected everything from zero on installation so there is not a cable connected where it shouldn’t be.

I actually joined this forum and thread just to give you feedback so I’m glad you answered, I really like the idea of the product and will happily help with feedback to make it work as supposed.

I can of course do a factory reset but that does not explain why threshold values are not taken in account in the works by the sg200?

Your explanation is how I thought it should be, but the sg200 does not respond to the values like it should (in my opinion).

//Jens

[lateral]

"Also, SoC can reach 100% without charge termination taking place"

Just as well that the SG200 doesn't actually "terminate charge" then. For those
that misconstrue, that the SG200 controls the charger.

I pay little attention to the SG200 SOC until it hits mid lower percentages as it is not
accurate on my setup at the top end. SOH, haha, mine gone back to 100% for 5yro
FLA batteries. Latest update worse than previous. (90%)
I bought this gauge for family, so they didn't have to do mental gymnastics.
My mistake.
I WILL post any change in performance with new updates.

[witzgall]

Jens,

Private message me your email address and we can work on the issue - I am sure there is an answer, even if I don't see it right away

Chris

Originally Posted by JensLB

I’m positive on both. Reconnected everything from zero on installation so there is not a cable connected where it shouldn’t be.

I actually joined this forum and thread just to give you feedback so I’m glad you answered, I really like the idea of the product and will happily help with feedback to make it work as supposed.

I can of course do a factory reset but that does not explain why threshold values are not taken in account in the works by the sg200?

Your explanation is how I thought it should be, but the sg200 does not respond to the values like it should (in my opinion).

//Jens

[JensLB]

Now I have collected some more data off the grid.

A few mornings ago I had the opportunity to monitor the monitor so to speak. Woke up with 89%SoC, beautiful morning and solar panel is doing it best to charge. Current flows in up to 8 amps and sometimes out a few depending on the households use. After going up to 93% it suddenly jumps to 100%+ SoC, at the moment I had a shown voltage in the high 12.80s and a current discharge of ~3amps.

Today woke up with 1A draw and voltage at 12.1V and a SoC at 74%, seems a bit high number I think...?

Solar panels been charging all day and we where up to 91% SoC at 6PM and shown voltage while charging a few amps was around 12,9V. I then took a shower and when I returned the sg200 shows 100%+!?!

Remember that I have a threshold voltage for 100%+ at 14.4V

I put this up so we can compare each others experience and learn how this monitor works. I replaced something else that was worse, so far I don’t want to throw the sg200 out, just understand how it works.

//Jens

[River Cruiser]

A question about installing, I have 2- 8-D batteries one starts both the port and starboard engines. The other is the house bank charged by the starboard alternator and a ProMariner 1260 onboard charger. The house battery has 2 cables on the ground side. How do I wire in the shunt? I assume both ground cables go to the shunt can someone verify this is correct?

[Prospective]

Originally Posted by River Cruiser

A question about installing, I have 2- 8-D batteries one starts both the port and starboard engines. The other is the house bank charged by the starboard alternator and a ProMariner 1260 onboard charger. The house battery has 2 cables on the ground side. How do I wire in the shunt? I assume both ground cables go to the shunt can someone verify this is correct?

Battery Neg to shunt battery side then connect other (load) negatives on other end of shunt. Ideally you'd have a ground buss bar so there's only one connection on each end of shunt.

[River Cruiser]

Correct, thank you that is my plan to install a -buss to make the connections.

[Wood]

Last chance for the SG200.

As previously posted I converted to LiFePO4. The SG200 reported 87% SOH fairly quickly and over 15 full and partial cycles has remained there. My initial load testing showed this to be false. Nominal capacity is 560AH. Actual more like 585AH.

Last week I drew the battery down to 3.0v per cell - or 12v for the battery. At 3.1v+ per cell - 12.4v+ battery, the SG200 was reporting 0% SOC. The BMS I am using reported over 25% SOC when the SG200 started reading zero. The BMS believes the battery is 100% SOH. The BMS and SG200 both report the same voltage and amperage under load and charge.

I charged the battery to a balanced 3.6v per cell - 14.4 v. The BMS reported 100% SOC a little before that. Acceptance had started to decline and was around 70amps. The SG200 was showing 92%. I switched to other batteries and let the lithium battery rest for several hours with no load / charge except for the SG200 [I turned off the BMS]. The readings remained the same.

Since this full charge there have been a few partial cycles from the engine alternator as I cruised back home.

On the mooring now - this morning the SG200 reported 55% SOC. The BMS reported 76%. I will be leaving the boat for a week so am charging so I can maintain refrigeration during my absence.

When charged I will factory reset the SG200. If it doesn't get with the program over the next few cycles I'm going to pull it out.