Strange B2B behaviour/ power drain

monzer

monzer

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2nd base
Seems to be a few things going on here so I will just throw a few things out there to see if anyone can make sense of what has gone wrong.

I have 2 125Ah KS batteries in the hab area with a Victron B2B feeding them. It's currently not putting in anything during long drives. It previously worked fine although I would sometimes have expected it to be putting a bit more in.

I had a play about with it and managed to get 5 or 6 amps going in but this soon fizzled out. When I turned off the 'output enabled' function in the B2B menu I was still getting 5 amps going in. Where is this coming from?

Turned on the cab heating to the only setting it works at (4 on the fan) and my readings of current in the leisure batteries dropped to -3ish amps. So cab electrics draining leisure batteries.

Can't seem to work out what is going on. Also the radio is now not getting power so it was a cold and boring drive up the road today.

Just parked up and Victron app was saying cab battery was at 12.9 with engine running (confirmed this with meter) engine off and it pretty much stayed the same.

Any ideas?
 
What victron b2b is it, as I’m just about to buy one…
 
Yes that’s the one I’m getting… will watch this with interest and hope you get it sort…
 
Another longish drive today and tried to find out a bit more. Starter battery does seem to be charging when engine running.

There seems to be an initial draw of around 5 amps coming out of my leisure batteries when engine first started. It settled down after a few minutes but if I put the cab heater on it takes a draw of 9 amps from leisure batteries.

It has to be B2B related to do this am I right?

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Kannon Fodda said:
When the B2B was fitted, was the original relay based charging system disconnected (which it should be)?
Click to expand...
That was my thought too. And if it wasn't & the base vehicle has a smart alternator, that might explain why the leisure battery appears to be draining into the vehicle battery.
 
First thing to check is- does the Starter battery input on the back of the EBL go straight to the 50 amp fuse by the starter battery or to the output of the B2B?
 
Kannon Fodda said:
When the B2B was fitted, was the original relay based charging system disconnected (which it should be)?
Click to expand...
I'm not entirely sure. I don't think the fitter wired it in a way to get maximum efficiency out of it. He said to do different would mean the fridge wouldn't work off cab battery when engine running. He also said it would involve a lot more wiring to run in.

Not confident with him to be honest.

I will say it has been working, albeit not putting in as much amps as I would like.

Only recently it has started taking power out the leisure batteries.
 
Lenny HB said:
First thing to check is- does the Starter battery input on the back of the EBL go straight to the 50 amp fuse by the starter battery or to the output of the B2B?
Click to expand...
I'll try and check this as soon as I get a chance. I think I'll probably have to get the big lumps of seats out to see exactly what wires are going where.

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monzer said:
I'm not entirely sure. I don't think the fitter wired it in a way to get maximum efficiency out of it. He said to do different would mean the fridge wouldn't work off cab battery when engine running. He also said it would involve a lot more wiring to run in.

Not confident with him to be honest.

I will say it has been working, albeit not putting in as much amps as I would like.

Only recently it has started taking power out the leisure batteries.
Click to expand...
Sounds like he didn't have a clue, shouldn't have any effect on the fridge.
I suspect he has wired the starter to the input of the B2B and the output to the leisure battery leaving the split charge relay in circuit which will mean it is in parallel to the B2B so making the B2B redundant. The spilt charge relay is inside the EBL.

If that is the case easy to sort just disconnect the starter Battery input from the EBL.

1706809947257.png
 
Last edited:
Lenny HB said:
Sounds like he didn't have a clue, shouldn't have any effect on the fridge.
I suspect he has wired the starter to the input of the B2B and the output to the leisure battery leaving the split charge relay in circuit which will mean it is in parallel to the B2B so making the B2B redundant. The spilt charge relay is inside the EBL.

If that is the case easy to sort just disconnect the starter Battery input from the EBL.

View attachment 861086
Click to expand...
Is the setup on the EBL99 similar?
 
monzer said:
Starter battery does seem to be charging when engine running.
Click to expand...
Alternator failed, it should be around 14v.
12.9v is near enough rested battery voltage.
Start the engine and keep at a fast idle, check volts at the battery with a multimeter, not onboard dials and gauges....should be around 14v

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pappajohn said:
Alternator failed, it should be around 14v.
12.9v is near enough rested battery voltage.
Start the engine and keep at a fast idle, check volts at the battery with a multimeter, not onboard dials and gauges....should be around 14v
Click to expand...
That was the other day. It did jump up to about 13.9 earlier today when I started engine.
 
Lenny HB said:
Sounds like he didn't have a clue, shouldn't have any effect on the fridge.
I suspect he has wired the starter to the input of the B2B and the output to the leisure battery leaving the split charge relay in circuit which will mean it is in parallel to the B2B so making the B2B redundant. The spilt charge relay is inside the EBL.

If that is the case easy to sort just disconnect the starter Battery input from the EBL.
Click to expand...
Even easier, just pull the 50A fuse near the starter battery.
monzer said:
I'm not entirely sure. I don't think the fitter wired it in a way to get maximum efficiency out of it. He said to do different would mean the fridge wouldn't work off cab battery when engine running. He also said it would involve a lot more wiring to run in.
Click to expand...
The fridge, starter battery mains trickle-charging and starter battery voltage measurement all happen via an entirely different wire, coming from the starter battery via a 20A fuse. So no problem if the main starter battery wire (with the 50A fuse) which feeds the split charge relay is disconnected.
 
Just smiffy said:
Yes that’s the one I’m getting… will watch this with interest and hope you get it sort…
Click to expand...
Go for Orion XS the 50A, even if you don’t need the full 50A you can set lower amps, running at very high efficiency. The older Orion 12-30 it gets hot, very hot at full potential.
The new Orion XS has VE direct port as well, you can integrate it properly with the rest of victron goodies.
 
Raul said:
Go for Orion XS the 50A, even if you don’t need the full 50A you can set lower amps, running at very high efficiency. The older Orion 12-30 it gets hot, very hot at full potential.
The new Orion XS has VE direct port as well, you can integrate it properly with the rest of victron goodies.
Click to expand...
Are you trying to confuse the poor lad. :rofl:

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Couple questions. What is the easiest way to gain access to back of ebl? Should I be able to gently lift it out of the wooden unit once the mains supply is disconnected?

And I see these fuses just above battery at back of engine bay? Would the big one be the 50A fuse mentioned in the thread before?

1000011845.jpg
 
Yes that is the one, does the input of the B2B go back to the red cable with the yellow terminal on the battery?
If so pull the fuse and see what happens.
 
Lenny HB said:
Yes that is the one, does the input of the B2B go back to the red cable with the yellow terminal on the battery?
If so pull the fuse and see what happens.
Click to expand...
Not confirmed that yet. I'm trying to trace them without removing any seats.
 
monzer said:
Not confirmed that yet. I'm trying to trace them without removing any seats.
Click to expand...
Disconnect that cable from the battery then use a meter on resistance to buss it through (extend the meter lead with a length of wire).
 
Usually the big (Maxi) blade fuse is the 50A, there will probably be a 20A standard size fuse which is the fridge etc, and maybe a 3A or 5A standard fuse for the D+ signal (the yellow wire?)

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Away from the van at the minute plus a bit stormy outside anyway but I'll be back to it when it settles down.

Thanks for your help guys.
 
I pulled the big red fuse, started engine and enabled the B2B. Nothing going into batteries but nothing coming out when cab heater fan etc is on which was happening before.

Went for a drive but nothing at all going in to batteries from the B2B.

Not traced any wires yet but going to have to do that tomorrow.

Attached are a few photos of the unit and settings.

1000011894.jpg


1000011893.jpg


1000011892.jpg


Do those settings look okay? As I've a feeling they may have reset after a recent update.
 
The heater van will be nothing to do with it that is a seperate problem.

You appear to have it set to smart alternator which you don't have.
I think the start voltage of 14v is a bit high.

First thing to check is the input voltage on the B2B with the engine running it should fairly close to the starter battery voltage.
 
Lenny HB said:
First thing to check is the input voltage on the B2B with the engine running it should fairly close to the starter battery voltage.
Click to expand...
Starter battery measured with meter was around 14.4 with engine on. B2B was showing the same (14.4-14.6) at the input. Green light is blinking which I think indicates bulk mode but shunt is showing nothing going in to leisure batteries at all.

I'm guessing I'll need to get my seats up to check wires in at leisure batteries now?
 
monzer said:
I'm guessing I'll need to get my seats up to check wires in at leisure batteries now?
Click to expand...
If the leisure battery is boxed in under the seat, then it's worth a quick check at the leisure battery fuse, which should be accessible without removing the seat. If you can't get the meter probe into the fuse slot, then you could temporarily stick in a standard blade crimp terminal and put the probe on that. If the wire from the battery terminal to the fuse is good, then it will give a good voltage reading. Not as foolproof as directly on the battery terminals, but the next best thing without removing the seat.

If the B2B output is reaching the fuse, then that's a start, at least you know the B2B is working.

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