Service battery being drained whilst switched off

[PaulRainbow]

Battery settings in the app at the bottom
View attachment 94631

Thanks Mark, i am aware of that menu option. But, clicking that alone does not actually calibrate the monitor, it simply zeros the current reading. If there really is a 20a current drain the monitor will zero, based on that, so the drain will be masked. To use the calibrate option it must first be established that the monitor is reading incorrectly and that there is in fact zero current flowing through the shunt, either by disconnecting the loads, or checking with an ammeter.

There is not usually a need to calibrate the current on a new install and i've never had to do it because of a battery change. For new batteries, the only thing to do, usually, is to set the ah, if needed.

 

[PaulRainbow]

Seeing posts like this, as a new browser, I am not sure if I wish to continue with my involvement. On the whole you do come over as being somewhat bombastic.

In post #15 Boater Sam made three statements that were potentially sending the OP on a wild goose chase, to me, that's not helpful, as i stated in post #22.

You appear to have a problem with that, but post #25 is OK?

Well I'll piss off then and leave it to you bombastic nerds. Don't know why I bother sometimes.

 

[pvb]

Very sad that you feel it clever to post like this.
As far as me knowing what is what, 56 years in the electronics industry after an apprenticeship building missiles would seem to make a mockery of your view.
You are not worthy to assess my qualifications.

I don't ever feel it's "clever" to post stuff. If I know enough to contribute sensibly, I may contribute. If I don't know anything about the query, I'll generally not contribute. I haven't assessed your qualifications, I've commented on your ability to advise. As PaulRainbow said, your comments weren't helpful, and only served to confuse.

 

[pvb]

This is exactly why I question my involvement here. Having don a historical search on persons relevant I find a trail of rudeness and what I would term as bullying.

If you're not happy here, you can always just not log in. If you stick around, you'll perhaps eventually realise that some posters offer sound advice.

 

[pvb]

Unfortunately this is prevalent in most forums.
There are some that I will no longer post on. But I enjoy trying to help people so I persevere. I ignore most of the rubbish but occasionally I just have to spit back a bit. Sorry to affect you, its only jousting.
Very late for me here so bed calls, night all,

Perhaps you might "help people" more if you only give advice on things you know something about.

 

[Spirit (of Glenans)]

Seeing posts like this, as a new browser, I am not sure if I wish to continue with my involvement. On the whole you do come over as being somewhat bombastic.

IMHO Paul Rainbow is a reliable poster on electrical and electronic topics as, it seems, he is a professional in this area. I wouldn't call him 'bombastic'. 'Confident' is how I would describe him.

 

[Spirit (of Glenans)]

I have a Nimbus motorboat with a bank of 3 x 80Ah service batteries.
I replaced them last week and also also installed a Victron app on my phone which displays the battery condition, via bluetooth from the Victron battery monitor. This makes it easy to see the current and voltage when going around the boat.
At anchor yesterday (first time on this boat), I found that even with the main service battery switch on OFF I had a continuous current drain of 17 to 20 amp, with corresponding drop in voltage. This may partly explain why I had to replace the old batteries, apart from them never having been topped up, and why the shorepower charger always seemed to be on.

There are clearly things which are wired not through the main battery switch, eg. feeds to two auto bilge pumps, maybe also the radio. I could not find anything running at all that would be taking this level of power, which was up to 250 watts. Something should be getting hot because of this rogue current flow...!

Has anyone some thoughts on what may be causing this situation?

The only thing I wondered is if the Mastervolt charger could somehow have a fault causing the current loss, because clearly it is connected to the battery bank.
I also have a Mastervolt Battery Mate, which controls the charging from the alternator across my 3 battery banks, engine, service and heavy gear (thruster & windlass).

My rather primitive but surprisingly effective method of approaching this kind of problem, in an automotive context, is simply to switch everything off, disconnect circuits one by one, and observe whether or not there is a spark when contact is broken.

 

[CLB]

There are a number of posters in YBW that really know their stuff. Some of them have a patient, calm way of getting their expertise across. Others are bolshy and clearly not able to deal in a civilised way with forum life. There are examples of both on this thread. Once you have learnt who falls into what camp, it is much easier to navigate your way around without getting drawn in.

 

[jamie N]

Loads of folks are sitting at their keyboards' wondering which camp they're associated with......??????

 

[JumbleDuck]

Loads of folks are sitting at their keyboards' wondering which camp they're associated with......??????

Is "Julian Clary" an option?

 

[Aardee]

I've already disconnected each wire, one at a time, from the 20 or so circuit breakers fed from the service battery bank. None of them made a difference to the 'rogue' current.

I'd suggest starting at the batteries and working outwards. Physically disconnect all positive connections and reconnect one at a time, testing as you go.

 

[VicS]

I'd suggest starting at the batteries and working outwards. Physically disconnect all positive connections and reconnect one at a time, testing as you go.

I agree with this

Disconnect all the wiring from the house bank positive terminal, except the (red) wire that supplies the battery monitor.

Check that the monitor now reads zero amps.................. If it does not then it is defective or the installation ( of the shunt) is incorrect

Assuming it does read zero reconnect the other wires singly, one at a time, until one of them gives the 20 amp reading, Then the faulty circuit is identified and can be investigated.

I suspect the 20 amps reading is a red herring and that the trouble lies with the installation. Id check the shunt installation very carefully against the installation guide and also check the cable between it and the display for damage or modification.

 

[Boater Sam]

??

 

[pvb]

I agree with this

Disconnect all the wiring from the house bank positive terminal, except the (red) wire that supplies the battery monitor.

Check that the monitor now reads zero amps.................. If it does not then it is defective or the installation ( of the shunt) is incorrect

Assuming it does read zero reconnect the other wires singly, one at a time, until one of them gives the 20 amp reading, Then the faulty circuit is identified and can be investigated.

I suspect the 20 amps reading is a red herring and that the trouble lies with the installation. Id check the shunt installation very carefully against the installation guide and also check the cable between it and the display for damage or modification.

Not necessarily, there's provision for zeroing the monitor, detailed in the manual, as I referred to in post 46.

 

[PaulRainbow]

Using an instrument that might be faulty, in a system that may have a 20a current drain, and a user who isn't sure what he's doing (no offence to the OP) ,to self calibrate seems less than 100% reliable to me.

Forget the monitor. Forget the batteries. Forget the anodes. Forget the shore power connection.

Connect an ammeter.

If it reads zero current, or thereabouts, the monitor is the problem. Carry out a factory reset, re-enter the battery ah and see how it reads. If it's still wrong, carefully check the installation and if necessary use the calibrate function. I would suspect that a 20a error in a correct installation is more likely to be a faulty monitor.

If it reads less than 20a, there problem is on the boat. Disconnect the loads one at a time until the ammeter drops and you have the faulty circuit. If the disconnected cable supplies more than one load, reconnect it and disconnect individual loads until you find the problem circuit.

As i said earier, not many things on a small boat that will genuinely draw 20a, inverter maybe. If it's a genuine 20a fault, that's serious stuff, don't leave the boat with the batteries connected.

 

[VicS]

Not necessarily, there's provision for zeroing the monitor, detailed in the manual, as I referred to in post 46.

I thought I had read that the monitor should read correctly straight out of the box but I suppose the zeroing could have been tampered with.
Does the provision for zeroing extend to as much as 20 amps ?

Using an instrument that might be faulty, in a system that may have a 20a current drain, and a user who isn't sure what he's doing (no offence to the OP) ,to self calibrate seems less than 100% reliable to me.

Forget the monitor. Forget the batteries. Forget the anodes. Forget the shore power connection.

Connect an ammeter.

If it reads zero current, or thereabouts, the monitor is the problem. Carry out a factory reset, re-enter the battery ah and see how it reads. If it's still wrong, carefully check the installation and if necessary use the calibrate function. I would suspect that a 20a error in a correct installation is more likely to be a faulty monitor.

If it reads -20a, there problem is on the boat. Disconnect the loads one at a time until the ammeter drops and you have the faulty circuit. If the disconnected cable supplies more than one load, reconnect it and disconnect individual loads until you find the problem circuit.

As i said earier, not many things on a small boat that will genuinely draw 20a, inverter maybe. If it's a genuine 20a fault, that's serious stuff, don't leave the boat with the batteries connected.

The trouble with connecting an ammeter is that the highest current range on most inexpensive digital multi meters is only 10 amps. It'll probably be Ok because the shunt just connects the 10 amp socket directly to the common negative socket but I'd nor advise anyone to connect a 10amp meter to a circuit whre the current might be 20 amps 'cos I would not want to be sent the bill for a new one .

The procedure I suggest will establish if the 20 amp reading is due to a faulty instrument, or as pvb suggests a zeroing error and it will identify a faulty circuit if one exits even though the 20 amp reading may not be accurate.
It also avoids having to explain how to measure current with a multimeter

I dont believe there is a 20 amp drain partly because the OP says the battery volts remain at 12.6 V. ( A 20 amp load would soon knock that down significantly.) and partly because 20 amps would be making something pretty warm

Bearing in mind the difficulty people have in correctly installing battery monitors, even the Victron ones, I am not going to be surprised if an incorrect monitor installation is the cause of the trouble

 

[pvb]

I thought I had read that the monitor should read correctly straight out of the box but I suppose the zeroing could have been tampered with.
Does the provision for zeroing extend to as much as 20 amps ?

I doubt it, but the Victron manual isn't specific.

Bearing in mind the difficulty people have in correctly installing battery monitors, even the Victron ones, I am not going to be surprised if an incorrect monitor installation is the cause of the trouble

The Victron monitor is almost a foolproof installation. The shunt and monitor are linked by a plug'n'play cable - nothing to get muddled with.

 

[VicS]

The Victron monitor is almost a foolproof installation. The shunt and monitor are linked by a plug'n'play cable - nothing to get muddled with.

I know. I know but that did not stop someone submitting a wiring diagram a few weeks back showing one incorrectly connected

Wiil look at the manuals again later .... gotta go for bloods now!

 

[PaulRainbow]

I thought I had read that the monitor should read correctly straight out of the box but I suppose the zeroing could have been tampered with.
Does the provision for zeroing extend to as much as 20 amps ?



The trouble with connecting an ammeter is that the highest current range on most inexpensive digital multi meters is only 10 amps. It'll probably be Ok because the shunt just connects the 10 amp socket directly to the common negative socket but I'd nor advise anyone to connect a 10amp meter to a circuit whre the current might be 20 amps 'cos I would not want to be sent the bill for a new one .

The procedure I suggest will establish if the 20 amp reading is due to a faulty instrument, or as pvb suggests a zeroing error and it will identify a faulty circuit if one exits even though the 20 amp reading may not be accurate.
It also avoids having to explain how to measure current with a multimeter

I dont believe there is a 20 amp drain partly because the OP says the battery volts remain at 12.6 V. ( A 20 amp load would soon knock that down significantly.) and partly because 20 amps would be making something pretty warm

Bearing in mind the difficulty people have in correctly installing battery monitors, even the Victron ones, I am not going to be surprised if an incorrect monitor installation is the cause of the trouble

You cannot reliably establish anything if the meter is faulty.

 

[PaulRainbow]

Oh, multimeters that read high DC current are hardly expensive, first random hit on Ebay:

UNI-T DIGITAL UT210E 100Amp 600V AC DC CLAMP METER Multimeter True RMS VFC diode | eBay

No doubt some cheaper ones if i wasted time digging around.

Not hard to explain how to use it, set to DC current, clamp over cable, read display.