Strange readings on battery monitor

[Dave_S]

I have just replaced my battery monitor a month ago, it has displayed expected readings until I ran my bi-annual recondition cycle on the battery charger. All the settings were checked before starting the charger and were the same settings used last time.

Don't know why the pics are all on their side but it shows 13.38V, normal for after running the recondition cycle, it usually drifts down to 13.2 at full charge before the recycle is due. The difference is it shows I'm at 66% charge and at -224ah. Normally it is 13.3/4 at 100% charge.

The recon cycle tests the capacity and it showed a pass.

The battery charger is not connected at the time of pictures. 6 x T105 Trojan batteries parallel and in series 12Vdc.

I ran the recondition cycle then topped up with distilled water, didn't take much, same as usual 6 batteries a total of about a litre. I noticed 1 battery only had a lot of growth of "stuff" on the neg terminal. It's now cleaned back to shinny metal and coated in vasloline.

I have put it back on the charger now on a maintenance cycle hoping it will be all good in the morning, but some how I think their run might be over.

Can anyone shed some light on what's happened.

A quick check of the batteries, none are hot one has some minor swelling. I am not sure if this is new swelling or old. It is hard to notice and I could have easily missed it before.

Normal use is just solar charging, no 240Vac only twice a year to precondition batteries.

[Dave_S]

On a seperate guage, the solar panel's show 0Amp input, normally if the batteries are low I can usually see 10 Amps going in, if at 66% maybe 20Amps. If the batteries are at 100% I see this analog guage at 0.

[Zanshin]

The Mastervolt monitor looks like a rebranded Xantrex LinkPro monitor. If that is the case, then the new monitor needs to be configured for the battery bank in question. The really important settings are:

• F1.0 - Float Voltage
• F1.1 - Float Current
• F5.0 - Battery Bank Capacity
• F5.4 - Peukert Exponent (get from Battery documentation)
• F5.5 - Self-discharge Rate

If these aren't set, then the battery monitor will not be able to compute the correct values.

[Dave_S]

Thanks Zanshin

It was installed professionally and did show 13.2V as 100% charged up until the reconditioning. Did the recondition cycle up set it somehow ?

I'm not sure what those values should be.

[sailorboy1]

disconnect power from it and then reconnect it

[Zanshin]

Removing power to the unit (there should be an in-line fuse on the + cable in the back) would just reset values and not solve your problem, perhaps even make it worse if only one of your parameters is incorrect.

Can you post the values for those parameters on this thread? Check the F5.0 to see if it matches the amp-hour capacity of your battery bank, that should be an indication of whether the default setting is there or if the monitor has been set.

[sailorboy1]

sorry but to me resetting it is a good first step before chasing your rear in around looking for something else

[Cpt Pat]

When the batteries were fully charged, did you reset the monitor state-of-charge display to 100%? Your posting implies you didn't. There are numerous other settings that you should verify. Read the monitor manual for instructions.

The installer shouldn't perform that reset-to-100% without first fully charging the batteries. That setting needs to be accomplished by the user (you).

If you have a quality charger, the float voltage will vary with temperature (see https://batteryuniversity.com/learn/article/charging_the_lead_acid_battery for an explanation). The voltage will also be temporarily higher immediately after a full charge. Many people call this temporary voltage boost a "surface charge." It's normal.

I don't want to be undiplomatic but your questions imply that you should spend some time studying battery theory. Here's a good place to start: https://batteryuniversity.com/

[olddog57]

Just want to follow this thread

[Cpt Pat]

One other note: Battery swelling is NOT normal. Your battery should have pressure-relief caps on the cells. These usually release gas (hydrogen) at around 5 psi. Some people just remove the caps during a reconditioning charge, and add distilled water as part of the process. The caps permit retaining some of the hydrogen gas during normal charging to reduce the amount of water you need to add (it recombines back into water). There is a limit to the rate at which these valves can release gas - charging at high currents makes this problem worse - and when overwhelmed will cause the battery to swell.

If the swelling is "minor," I wouldn't worry about it.

[BruceS]

If it's similar to a Victron monitor just wait for a 24hr cycle & it'll reset itself.
The settings won't change by disconnecting or resetting the SOC. (State Of Charge) Just don't reset to factory settings!!

[Cpt Pat]

Originally Posted by BruceS

If it's similar to a Victron monitor just wait for a 24hr cycle & it'll reset itself.
The settings won't change by disconnecting or resetting the SOC. (State Of Charge) Just don't reset to factory settings!!

As noted by another poster above, your monitor appears to be a rebranded Xantrex monitor. If so...

"... manually synchronize the battery monitor with your battery when you are sure your battery is fully charged. This can be accomplished by pressing both < and > keys simultaneously for three seconds. After these three seconds, the flashing FULL message appears on the display just like when it is automatically synchronized."

If you would like to RTFM, here's the manual: http://www.xantrex.com/documents/Acc...-01_Rev-E).pdf

[BruceS]

You change your post Capt Pat?
So does your Victron do it or not?


My Victron BVM-702 doesn't behave that way. As noted by another poster above, your moni

[Dave_S]

I did the "hold < > " for 3 seconds and reset to 100% which worked ok except my batteries are now down to 12.95V which is not normal.

F1.0 - Float Voltage = 13.2V
F1.1 - Float Current = 2%
F5.0 - Battery Bank Capacity = 675 Ah
F5.4 - Peukert Exponent (get from Battery documentation) = 1.25
F5.5 - Self-discharge Rate = OFF

[sailorboy1]

Originally Posted by Dave_S

I did the "hold < > " for 3 seconds and reset to 100% which worked ok except my batteries are now down to 12.95V which is not normal.

What's "not normal" for that as that's more than a resting battery fully charged?

Is you charger really on?

Did you manually measure the voltage at the battery and compare to the BM reading?

I don't see any way so far from the info to know if you have a BM problem, a battery charger problem, or a battery problem, or no problem. (maybe I missed reading a key clue)

My suggestion is to turn off your battery charger a while and watch and note on the BM what the amps/voltage/SOC is for a day. There turn on the battery charger and note the same and be sure that before the BM gets to 100% that of charge that the battery is at absorption voltage and accepting less than 0.5%C