Balmar SG200 SOC Meter

[sbman]

Dockside, I used battery power overnight. I started the engines and and ran them at 1,200 RPM and observed the charging on the Balmar app. It started at 60 amps each bank at 12.9 volts. Then I switched to the inverter charger which is rated at 125 amps. The charging rates to each bank were virtually the same. Would the charge acceptance rate of my batteries be part of the equation? I profess ignorance.

The initial charge acceptance rate will increase as the bank is depleted. The particular chemistry will drive the maximum rate with flooded being the lowest due to it's high internal resistance relative to other chemistries.

If you only used 20% of your capacity overnight (which seems reasonable), the acceptance rate will still be fairly low, but will still be highest at the initial start of charge and then curve down from there to a trickle at 90-100% SOC. Deeper depletion will increase the initial charge acceptance rate. I would expect a higher rate than 60 amps, at least for 2-5 minutes even with only 20% depletion. Note that it takes up to two minutes for the Balmar to ramp up to full bulk charge mode.

60 amps for a 100 amp alternator at 1200RPM engine could be correct depending on your pulley sizing, perhaps your alternator is turning slower than you think. Calculate or measure your alternator RPM and check the output curves for your model:

https://balmar.net/balmar-technology/alternator-output-curves/

Other things to verify include:

• Where is your positive battery sense wire connected to? (Terminal 9 on the MC-614)
• Which profile are you using on the MC-614?, have you customized it?
• What voltage is present when you are seeing 60 amps of charge?

You can see the temp of the alternator on the MC-614 display in Celsius. Look at the display and wait for the 'AL' to show, the next number shown is the temperature detected. Scaling back of charge starts at 100C with default settings.

 

[FlyWright]

The battery bank can only accept so much if its tapering charge profile, regardless of how much juice is being provided. It's like having more water in the funnel than needed to gravity feed a hose...it's not gonna flow through any faster.

Your greatest risk of overheating a Balmar alternator is when the bank is very low, temp sensing is misconnected and adequate cooling does not exist. DAMHIK...

 

[DDW]

Dockside, I used battery power overnight. I started the engines and and ran them at 1,200 RPM and observed the charging on the Balmar app. It started at 60 amps each bank at 12.9 volts. Then I switched to the inverter charger which is rated at 125 amps. The charging rates to each bank were virtually the same. Would the charge acceptance rate of my batteries be part of the equation? I profess ignorance.

If you are only charging 60 A at 12.9 volts something is set up wrong, or your source is amp limited. The inverter charger is feeding two banks, each at 60A? then that is limited by the charger's 125A being split two ways. Each alternator may only be putting out 60 A as well. If the battery's charge acceptance was the problem, the voltage would be 14.4.

Basically what you should see is current going into the battery limited only by the charging source, with voltage ramping up until it reaches 14.4 or so. Then the charge regulator will keep it there, and taper off the current to do so. When the current reaches a very low value (0.5% of the battery capacity) it should switch to float, dropping to around 13.5V. The Balmar 614 will switch way too early because of the ancient design, but the inverter charger should not.

 

[sbman]

If you are only charging 60 A at 12.9 volts something is set up wrong, or your source is amp limited. The inverter charger is feeding two banks, each at 60A? then that is limited by the charger's 125A being split two ways. Each alternator may only be putting out 60 A as well. If the battery's charge acceptance was the problem, the voltage would be 14.4.

Basically what you should see is current going into the battery limited only by the charging source, with voltage ramping up until it reaches 14.4 or so. Then the charge regulator will keep it there, and taper off the current to do so. When the current reaches a very low value (0.5% of the battery capacity) it should switch to float, dropping to around 13.5V. The Balmar 614 will switch way too early because of the ancient design, but the inverter charger should not.

Very well said, however the Balmar regulators don't taper current, they have no way to do so, they only control output voltage. That may sound like semantics, but it's a big difference.

Bulk charge starts with an 18 minute run that regulates the output voltage of the alternator trying to get it to 14.6 volts, so the charge current is limited by the alternators charging ability until 14.6 volts is reached. After 18 minutes it does it's best to calculate how much longer to keep doing that, setting a timer. When the timer runs out it moves to absorb where it holds 14.4 volts for another timed period, eventually switching to float voltage of 13.4. During all of this charging profile it monitors temp of batt and alt (if installed) and scales back output voltage if over temp is detected. It never responds to any amp based data because it has none to work with.

That's why it's so important to make sure you have the battery voltage sense wire directly on the terminal of the battery, because that's where the regulator is going to drive the voltage output. If your alternator cables are undersized and you are sensing at the alternator terminal then you can lose a lot of voltage just from the alternator cabling.

It's still possible that the alternators may be turning slower than you think, and that will limit their output. Rev up and see if it increases the charge. check the temp readout on the Balmar to see if it thinks they are overheating.

The last Balmar install I did was putting out 380 amps continous during the initial bulk phase, dual 200 amp large frame, serpentine belted brushless alternators doing thier job. You really need to be making sure all your wiring is well sized and well implemented when you start dealing with high current!

Another note for CatalinaJack, you should never run the Centerfielder based system with your banks separated (Which you never said you were doing, I realize). The system works by driving both alternators from the same regulator once it 'joins' them, so if you run with the banks split, you will be blindly charging one bank with no voltage feedback from one of the banks, potentially a very bad situation

 

[FlyWright]

If your alternator cables are undersized and you are sensing at the alternator terminal then you can lose a lot of voltage just from the alternator cabling.

Great point about alternator cabling. My boat (and many) came with a small wire running from the alternator to the start cable on the starter so the large starter cable could be used for 2-way (load and charge) electron flow. It is cheaper and lets the alternator charge flow into the battery bank...at least that portion that can be passed by that small gage wire from Alt to Batt.

I recabled from alts directly to batts (appropriately fused, of course) with #4 cable.

"All cable size matters" when pushing lots of electrons.

 

[sbman]

Great point about alternator cabling. My boat (and many) came with a small wire running from the alternator to the start cable on the starter so the large starter cable could be used for 2-way (load and charge) electron flow. It is cheaper and lets the alternator charge flow into the battery bank...at least that portion that can be passed by that small gage wire from Alt to Batt.

I recabled from alts directly to batts (appropriately fused, of course) with #4 cable.

"All cable size matters" when pushing lots of electrons.

Yes it does. We melted a 3" long 2/0 cable with 380 amps continuous charging. We had a bad crimp I'm pretty sure, but it was replaced with a solid copper bar. I always recommend people use an IR temp gun to check electrical connections on a regular maintenance schedule and when the system is working hard. It's a good preventative maintenance task.

The next time I put together a system that wants that kind of charge power, I will move to a 24V or 48V house bank.

 

[FF]

. My SOH shows 100% after cycling six times. I would have thought it to be lower given that the batteries are four years old.

The unit shows the percentage of charge on the batts as they are , not what the mfg claimed years ago.

 

[catalinajack]

. My SOH shows 100% after cycling six times. I would have thought it to be lower given that the batteries are four years old.

The unit shows the percentage of charge on the batts as they are , not what the mfg claimed years ago.

If your batteries are flooded lead acid, don't FLAs take as many as 40 - 50 deep cycles (50% SOC) to reach their full potential before beginning their downward course to lower states of health? In your four years on these batteries have they been cycled enough?

 

[Codger2]

Bowmar SG200 showing "High Voltage" when charging

I've had this Duffy for almost a year (since new) and during the last 2 charges the SG200 is showing a "High Voltage Alarm." My knowledge of battery chargers can be fully contained in a thimble. I've been told that a high voltage alarm can shorten the life of the batteries considerably. I have a 48 volt system consisting of 16-6 volt AGM batteries. What do the "electrical gurus" on this forum say?

 

[sbman]

If you are using the 'flooded' profile on the SG200, on a 48 volt bank and default settings on the SG200, then that means the charge voltage is exceeding 65.2 volts

That's equivalent to 16.3 volts per '12 volt' battery. That's outside the typical safe voltage for flooded batteries, you'd have to check with your battery specs to see if it falls outside of their acceptable charge voltage range.

 

[ssobol]

I've had many alarms from my SG200. High current, low current, high voltage, low voltage, low level.

I get low current alarms because the alarm limit is set to zero and when the battery is off, there is no current.

There doesn't seem to be any way that I've found to change the alarm trip points.

I only use this meter to see the battery charge level, voltages, and the current in/out. Even then, the charge level is suspect. I keep it mostly because the display is much easier to see than the Victron meter I had before. The rest of the "features" I ignore.

And yes, I keep the SG200 software up to date.

Granted, my boat is small and only has one house battery of 75 amp hours (plenty for my situation) that does not get discharged all that far in normal use. This is apparently not optimum for the SG200.

 

[FlyWright]

I hope CMS comes on for this one, Walter. He will know. You could always PM him.

 

[Codger2]

I hope CMS comes on for this one, Walter. He will know. You could always PM him.

Al. Who is CMS?

 

[Comodave]

Compass Marine of marinehowto.com

 

[FlyWright]

Al. Who is CMS?

Click the link...send him a PM.

 

[Codger2]

I hope CMS comes on for this one, Walter. He will know. You could always PM him.

In the last two weeks I finally got in touch with the SG200 Guru at Balmar in Washington. His name is Dan and he appears to be quite knowledgeable! He admitted to getting a lot of complaints on the "high voltage alert" question and told me that it's a Firmware problem and that Balmar is releasing an update any day now to solve this problem. You must have a Balmar Bluetooth Gateway that plugs in to the back of the SG200 and when the company sends a link to your smart phone, you can update the SG200 easily. In the meantime I have experienced getting rid of these alerts by doing a super simple "Device Reset." (Not a factory or a network reset.) I was told by Tim, in the same department as Dan, that "even a millisecond spike causes the gauge to alert. The"device reset" will work to keep the faults from appearing but the faults will come back," which indeed they did! In the meantime I continue to trust the SOC, Amps, Voltage, time to go, etc. as the gauge seems to be working correctly. By watching the amps you can see what various 110v appliances are using, amp wise, while on the inverter. Although I haven't unplugged the shore power to keep the Charger from coming on and reducing the SOC to 40% or less, it's on my list but is not in the "must do" category at the present time. Cruising my boat with the gauge set to SOC, you can see the SOC percentage drop as the hours go by. A much better indication of SOC than the dumb E...F gauge that that Duffy provides. (I can see why Duffy does this as their market seems to be "boating novices" that wouldn't know what a good SOC meter is telling them anyway!)


So far, my experience with an all electric boat has been fascinating as I'm just finishing my first year with the boat.

 

[socalrider]

Thanks for your update Codger!

I finally gave up on mine & have removed it from the boat. If anyone wants an SG200 + Gateway make me an offer!

 

[ssobol]

I often get a low current alarm. It says the current is 0 and the trigger level is zero.

 

[catalinajack]

Thanks for your update Codger!

I finally gave up on mine & have removed it from the boat. If anyone wants an SG200 + Gateway make me an offer!

Mine works perfectly. I really wonder why some folks have no problems while others have nothing but trouble.

 

[socalrider]

Mine works perfectly. I really wonder why some folks have no problems while others have nothing but trouble.

It's the solar that trips it up in my case. I get the fault alarms but those are just a nuisance. Solar charging seems to confuse it and resets SOC.

 

[catalinajack]

Here's my report on a successful SG-200 installation and an opinion as to whether it is worth the bother. In addition to the SG, I also have a Series 700 Victron monitor and the Magnum remote control/monitor for a Magnum 2812 inverter/charger. With that, here is one real-world comparison.

1. The Magnum and the Victron report the same number of amp-hours consumed.
2. The SG-200 does not display amp-hours consumed, only a State of Charge (SOC). Note: the SG-200 must be internally counting amp-hours to arrive at the same SOC as does the Magnum.
3. The SG-200 reports the same SOC as the Magnum but the Victron consistently reports a SOC 4% higher. Note: I have no explanation for this anomaly. I trust the Magnum and SG-200 in this regard. Perhaps the Magnum and SG-200 handles the Peukart's factor in a different way.

Conclusions:

1. For my system (no wind, no solar) I do not need anything more than the Magnum remote panel. The other two gizmos have confirmed that it is accurate.
2. The Victron is redundant, not needed but some folks like redundancy.
3. The SG-200 is not needed but very nice to have, but expensive for what the "nice-to-have" is. The SG-200 blue tooth app reports SOH (State of Health) and, yes, it works on my system. It also shows real time charging amps and voltage. I find it handy when cruising to see what the alternators are doing or the charger on shore power. Just an hour ago, the marina turned the electricity back on after the tide went out (Kent Narrows, MD) and the flooding receded here. Yup, the SG-200 immediately showed 125 amps going into the batteries with a slowly rising voltage, exactly what one would expect. As I said, nice to have.

By the way, if I were installing all now, I would choose to have the Magnum remote and the SG-200 instead of the Victron. The Victron tells me nothing that the Magnum remote does not. Yes, the Victron does offer some control features but the Magnum remote has the same capabilities.

One last observation about the Victron, their 2-inch dials are VERY difficult to read.

 

[ssobol]

... One last observation about the Victron, their 2-inch dials are VERY difficult to read.

One of the big reasons I got rid of my Victron.

 

[Codger2]

One of the big reasons I got rid of my Victron.

+1

 

[catalinajack]

+1

Yes, the Balmar is the same size but there's an app for that.

 

[Codger2]

In the last two weeks I finally got in touch with the SG200 Guru at Balmar in Washington. His name is Dan and he appears to be quite knowledgeable! He admitted to getting a lot of complaints on the "high voltage alert" question and told me that it's a Firmware problem and that Balmar is releasing an update any day now to solve this problem. You must have a Balmar Bluetooth Gateway that plugs in to the back of the SG200 and when the company sends a link to your smart phone, you can update the SG200 easily. In the meantime I have experienced getting rid of these alerts by doing a super simple "Device Reset." (Not a factory or a network reset.) I was told by Tim, in the same department as Dan, that "even a millisecond spike causes the gauge to alert. The"device reset" will work to keep the faults from appearing but the faults will come back," which indeed they did! In the meantime I continue to trust the SOC, Amps, Voltage, time to go, etc. as the gauge seems to be working correctly. By watching the amps you can see what various 110v appliances are using, amp wise, while on the inverter. Although I haven't unplugged the shore power to keep the Charger from coming on and reducing the SOC to 40% or less, it's on my list but is not in the "must do" category at the present time. Cruising my boat with the gauge set to SOC, you can see the SOC percentage drop as the hours go by. A much better indication of SOC than the dumb E...F gauge that that Duffy provides. (I can see why Duffy does this as their market seems to be "boating novices" that wouldn't know what a good SOC meter is telling them anyway!

I wrote this on October 28, 2021 and at that time the Firmware release did not solve the "High & low voltage alerts". The most recent Firmware release does solve the problem!