What would cause a DC voltage spike??

[Prospective]

Here are the details...

Boat kept in slip on shore power. All systems normal after last cruise. Per my usual, I leave my Victron inverter/charger ON in CHARGER ONLY mode. New house bank and start bank of 3 and 2 respectively Group 31 AGM batteries attached via an ACR. I visit boat periodically, nothing out of normal.

Come to boat after last having taken it out 5 weeks prior and see my Balmar SG200 battery monitor showing a warning indicating there was high voltage at some point. Indicated voltage reached 15.03V. Charger is set to float/maintain at 14.3V and voltage was showing 14.3V at this point.

Any ideas what would cause a voltage spike? DC power is being provided by the battery bank and charger. I don't believe there were any electrical storms but their may have been a rumble or two of thunder at some point. Hard to pinpoint.

 

[gsholz]

To see what is going on, "Invest" in a logging bluetooth battery monitor. It will log battery voltage for days and display on your phone when you get back to your boat. You do not need to be close to the battery reading voltage or log. Less than $30.

https://www.walmart.com/ip/12V-Bluetooth-4-0-Car-Battery-Monitor-Car-Battery-Tester-for-Android-4-3-for-iOS-7-1/258259939?wmlspartner=wlpa&selectedSellerId=18988&adid=22222222222000000000&wmlspartner=wmtlabs&wl0=e&wl1=s&wl2=c&wl3=10352200394&wl4=pla-1103028060075&wl5=&wl6=&wl7=&wl10=Walmart&wl11=Online&wl12=258259939_10000020145&wl14=bluetooth%20battery%20monitor&veh=sem&msclkid=8ee42ef146c21adf38c94f9c93a1dbe3&gclid=8ee42ef146c21adf38c94f9c93a1dbe3&gclsrc=3p.ds

I used it to identify why my house bank always charged at 60A whenever I got back to the boat. Should have been fully charged. Turns out my fancy charger did not re-start charging from float until a significant voltage drop.

 

[Codger2]

Any ideas what would cause a voltage spike?.

I had almost an identical alert on my SG200 2 weeks ago. I thought it might be the charger, etc but when I talked with Balmar engineering they said no, it's a bug in the Firmware. A fix is in the works (2 weeks) and your gauge must be updated with the latest software change. I've been told that you must have a Bluetooth Gateway (40 or 50 bucks) then you can update direct to the gauge via smart phone. The Bluetooth connection is on the back of the gauge. I got rid of the alert(s) on my gauge by doing a "device reset".) Not a factory reset or a network reset.) I mentioned this to the Balmar tech and he said the fault will return until the Firmware is updated. I don't know which Bluetooth gateway is needed as I haven't made the purchase yet. BTW, you & I are not the only ones with this problem as numerous others have experienced it also. I'll will re-post as soon as I have fixed the problem. (Note: I have an electric boat that has 16-6volt batteries & is a 48 volt system.)


The tech also said that they are updating Firmware periodically with fixes and enhancements to the SG200. (There have been 3 in 2021 so far!) As this product evolves, it should be fantastic and all changes can be done to your gauge as described above.

 

[Prospective]

Wow, thanks for the info. I have the blue tooth gateway and am familiar with the software update process. Boats going away for winter but I always check for updates at beginning of season.

 

[hobbystuff]

Your Victron Inverter/Charger has a "Repeated Absorption Interval" that it cycles through on a regular time period (I think the default is 7 days or something like that - it is configurable) where it moves to absorption for a short period.

Depending on the battery temperature, and the temperature compensation setting, it is possible to see 15V when the batteries are cold. I monitor my boat through the Victron VRM Portal and can see it happen regularly.

 

[Prospective]

Well... that's interesting too. Although I've had the SG200 for a couple of years now and the Victron for 5+ years. This is the first time I've seen the warning.

 

[Codger2]

Well... that's interesting too. Although I've had the SG200 for a couple of years now and the Victron for 5+ years. This is the first time I've seen the warning.

At present, even a millisecond spike in voltage will trigger the voltage alarm. The proposed change to the Firmware software should rectify this.

 

[Bmarler]

regarding the balmar smart gauge, does it count amp hours? i looked at the website and it seems to display time remaining instead of hours. is that correct?
looks like a really nice monitor though.

 

[catalinajack]

regarding the balmar smart gauge, does it count amp hours? i looked at the website and it seems to display time remaining instead of hours. is that correct?

looks like a really nice monitor though.

It does not display amp hours but it does count them internally in order to arrive at a percentage State of Charge. Percentage times size of bank equals amp-hours consumed

 

[GoneDiving]

To see what is going on, "Invest" in a logging bluetooth battery monitor. It will log battery voltage for days and display on your phone when you get back to your boat. You do not need to be close to the battery reading voltage or log. Less than $30.

https://www.walmart.com/ip/12V-Bluetooth-4-0-Car-Battery-Monitor-Car-Battery-Tester-for-Android-4-3-for-iOS-7-1/258259939?wmlspartner=wlpa&selectedSellerId=18988&adid=22222222222000000000&wmlspartner=wmtlabs&wl0=e&wl1=s&wl2=c&wl3=10352200394&wl4=pla-1103028060075&wl5=&wl6=&wl7=&wl10=Walmart&wl11=Online&wl12=258259939_10000020145&wl14=bluetooth%20battery%20monitor&veh=sem&msclkid=8ee42ef146c21adf38c94f9c93a1dbe3&gclid=8ee42ef146c21adf38c94f9c93a1dbe3&gclsrc=3p.ds

I used it to identify why my house bank always charged at 60A whenever I got back to the boat. Should have been fully charged. Turns out my fancy charger did not re-start charging from float until a significant voltage drop.

Looks great. Is anyone aware of a 24 or 48v version?

 

[KnotYet]

Looks great. Is anyone aware of a 24 or 48v version?

An inexpensive DC-DC converter chip may be able to provide the voltage change.

These are commonly used for folks that want to use 12V accessories in a golf cart.