Lenny HB
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- Oct 18, 2007
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- Since 2008 & many years tugging
Was that with or without the 50 amp fuse?
Strange B2B behaviour/ power drain
- Thread starter monzer
- Start date
OP
OP
That fuse is still out.
Lenny HB
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- Oct 18, 2007
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That then looks like the cable with the yellow terminal is the B2B input.
What state of charge are the leisure batteries as if nearly charged the B2B will shut down.
I would discharge the batteries to at least 80% then try it.
TheBig1
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- Nov 27, 2011
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the output wires on the b2b should show the leisure battery voltage with the engine off
The leisure battery powering the heater in the cab suggests that a relay is shorted or failed connected
The leisure battery powering the heater in the cab suggests that a relay is shorted or failed connected
OP
OP
They were at about 60% when I did that measuring. And B2B telling me it's bulk charging. Just not getting an input into the batteries.
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OP
OP
I'll check that tomorrow thanks. How come removing that fuse has stopped the heater taking power out the LB's? Apologies if it has been explained already, I'm only just keeping up with the solutions posted here.
Lenny HB
LIFE MEMBER
- Oct 18, 2007
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That fuse is the starter battery connection to the EBL and connects to the split charge relay inside the EBL.
I can't see how this can have any effect on the cab heater.
I'm clutching at straws a slight possibility the split charge relay is seized closed, it that is the case the starter batteries and leisure batteries would be exactly the same voltage with the fuse in.
I can't see how this can have any effect on the cab heater.
I'm clutching at straws a slight possibility the split charge relay is seized closed, it that is the case the starter batteries and leisure batteries would be exactly the same voltage with the fuse in.
OP
OP
Would that be the relay in the EBL or elsewhere?
I'll check the fuse as in autorouter 's post then go from there.
Just don't like lifting the seats off as it is awkward and perfectly suited to popping my back out again.
The split charge relay is inside the EBL.
There is a way to test if the split charge relay is stuck closed or not. It may be difficult to get at the battery terminals and the power terminals at the back of the EBL, but you should be able to get at the two 50A fuses (one for the starter feed, one for the leisure battery feed).
On each of the fuses, one fuse terminal is on the battery side, and should be permanently live. The other fuse terminal is on the load side, and should not be live unless the fuse is inserted.
The split charge relay connects the load side of both fuses. So if you remove the fuses, and check the resistance between the two load side terminals, it will be very high if the split charge relay is open, and very low (less than say 5 ohms) if the split charge relay is closed. Of course when the engine isn't running, the split charge relay should be open - if it's not, then you have a stuck split charge relay, as Lenny HB suspected. If it's open, you could even start the engine and check that the split charge relay closes.
For this resistance test, the circuit should not be powered, so that's why I say to remove the two 50A fuses. If it's powered, you will get false readings.
An even simpler test: If you remove one of the 50A fuses, then one side should be permanently live, and the other side should not be live. If it isn't live, then the split charge relay is open, so it's not a problem. If it is live, then it is getting the live from the other battery, through the other 50A fuse, and through the stuck split charge relay. Then if you remove the other 50A fuse, it should stop being live. That confirms the split charge relay is stuck closed.
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OP
OP
Thanks for that but I think we have reached the limit of my understanding on this issue. I'll check from B2B to batteries later on but if no problem found there I'll have to put it to someone.
Really missing the power input from driving especially at this time of year so gonna have to get it sorted.
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OP
OP
Wow nearly a year after this thread was started and only now am I actually getting the benefits of the B2B. Whatever the issue was I think it fried my alternator. I put the van in to a garage and told them to investigate this issue and I got it back a few weeks ago with everything seeming to be working great.
My batteries were down at about 25% and nearly full via the B2B after a longish drive from Glasgow to Aberdeen. The B2B is also working well at replacing what electric I use the night before with short drives during the day. This is great as it is exactly what I bought the unit for.
Only thing is, I would like the shunt to represent more accurately what the B2B is doing. The B2B was wired after the shunt so not sure how they have done it but the Victron app is only showing approx 6-10 amps going in to batteries where as the KS app shows a higher current going in which is what I would expect and seems to tie in with what I am finding re battery capacity.
My batteries were down at about 25% and nearly full via the B2B after a longish drive from Glasgow to Aberdeen. The B2B is also working well at replacing what electric I use the night before with short drives during the day. This is great as it is exactly what I bought the unit for.
Only thing is, I would like the shunt to represent more accurately what the B2B is doing. The B2B was wired after the shunt so not sure how they have done it but the Victron app is only showing approx 6-10 amps going in to batteries where as the KS app shows a higher current going in which is what I would expect and seems to tie in with what I am finding re battery capacity.
You need to look at exactly how the shunt is wired into your system. First, is it wired on the negative terminal of the battery, which is the usual arrangement, or is it wired on the positive battery terminal (a possible but less popular arrangement.)?
If it's on the negative terminal, a common mistake is to leave the chassis earth connection still connected to the battery negative terminal. It needs to be taken off the battery negative terminal and connected to the load side of the shunt. It may be necessary to crimp a new eyelet terminal onto the wire to allow it to be connected to the shunt.
Is to a busbar acceptable?
Mike.
OP
OP
Looking back through a thread I had when putting the shunt in, I reckon I settled on this way of wiring it in....
What would have been the best way to add a B2B in to that system? I have no idea how they wired that in.
That doesn't look right at all. Can you clarify which battery (1 or 2) is the starter battery and which is the leisure battery?
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I assume both are leisure batt's and that looks ok.
B2B in parallel with the loads, and you will see the b2b output on the shunt less loads at that moment.
If you want to see true b2b output, you need another separate shunt on the b2b output as energy meter.
B2B in parallel with the loads, and you will see the b2b output on the shunt less loads at that moment.
If you want to see true b2b output, you need another separate shunt on the b2b output as energy meter.
Deleted to avoid confusion.
Edit: If as Raul says the two batteries are both leisure batteries then as he says it's OK. But the problem would probably be related to how the chassis was connected - it should go to the Shunt System terminal. Also the B2B negative terminal should be wired to the Shunt System terminal.
Then the B2B Leisure battery terminal should be wired to the leisure battery positive, preferably the same one as the MPPT and loads. And also the B2B Starter battery terminal should be wired to the Starter battery positive.
Edit: If as Raul says the two batteries are both leisure batteries then as he says it's OK. But the problem would probably be related to how the chassis was connected - it should go to the Shunt System terminal. Also the B2B negative terminal should be wired to the Shunt System terminal.
Then the B2B Leisure battery terminal should be wired to the leisure battery positive, preferably the same one as the MPPT and loads. And also the B2B Starter battery terminal should be wired to the Starter battery positive.
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OP
OP
Sorry, yes that is my diagram from when I was fitting 2 new leisure batteries along with the shunt.
I'll need to find a bit of time over the holidays to get the driver and passenger seats out so I can get a good look at how the B2B is wired in. If it seems relatively straight forward I shall have a go rewiring as the above post as it would be handy having more accurate readings in the Victron app.
I'll need to find a bit of time over the holidays to get the driver and passenger seats out so I can get a good look at how the B2B is wired in. If it seems relatively straight forward I shall have a go rewiring as the above post as it would be handy having more accurate readings in the Victron app.
Look at engine shutdown detection and check the start voltage, in your photo it's set at 14 volts, if it's still set at 14 volts change that to 13.25 and the delayed start voltage to 13.20 and see if you get a greater charge current, it's a peculiarity of the Victron B2B charger that the default setting throttles the output, I learnt this from one of RogerIvy video and it worked on mine.
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