Flat starter battery

Phantom

Full Member
Posts
466
Likes
510
We've been parked up on EHU for the last 3 weeks with the onboard charger keeping the hab batteries topped up but it doesn't do the starter battery. We have a battery master that is supposed to send 0.5Ah from LB to SB when there is 0.5V difference. I went to start up the moho today but SB was flat and showing just under 12v. Thinking about it I changed my solar controller a few weeks ago, the old one charged both batteries but this one doesn't so maybe the battery master is not doing it's thing? I'll have to do some checks tomorrow and also see if there is a drain on SB.
To charge the SB I removed it (was a right pig to get out) and connected it to LBs with jump leads and the onboard charger seems to be charging it, though at a lower voltage than the LBs. The SB is about 2 years old and surprised that it went flat in just 3 weeks. Alternatively I guess I could have just swapped the battery wires over at the solar regulator but would have been a very slow charge.
 
My dual battery solar charger packed in last year after only 2 years, so I bought another off Fleabay, Then afterwards I thought if this packs in abroad we could be stuffed so for a tenner I've ordered another to carry as a spare
That is the one I replaced but keep as a spare. 😄
 
My dual battery solar charger packed in last year after only 2 years, so I bought another off Fleabay, Then afterwards I thought if this packs in abroad we could be stuffed so for a tenner I've ordered another to carry as a spare
At that price its a pwm and not a much better mppt like this with duel output, 1 ah to starter.
solar duel a.png
 
Not had chance to check the wiring yet but I've just found out the cause of my flat SB. The battery master has always displayed a green light so I just assumed that meant that it was working okay. But have now read that green just indicates that the SB and LB's are balanced and should change to red when charging SB, which it never has. So should be an easy fix unless a problem with the device itself. 🙄
 
This one reckons to charge SB at 1.1AH when it detects 0.8V difference, though sure I read some slightly different specs before? 🤔
 
Check fuses, my EBL charges my starter battery as well as my habitation batteries when i plug generator in which is the same as you going on ehu. If your Phantom is like mine you will have a 50amp fuse with a smaller fuse holder piggy backed on it. When mine stops charging its the smaller fuse.
 
Check fuses, my EBL charges my starter battery as well as my habitation batteries when i plug generator in which is the same as you going on ehu. If your Phantom is like mine you will have a 50amp fuse with a smaller fuse holder piggy backed on it. When mine stops charging its the smaller fuse.
I had previously mistakenly assumed that the Durite VSR was supposed to be charging LB, but today figured that it is actually for the fridge when on 12v, which I had expected to have been fed from EBL?
A previous owner had a separate Zig X70 charger fitted which is directly connected to
LB as solar is, so neither charge SB alone. Even if the EBL internal charger is dead then surely the external replacement could have been connected the same way to charge SB also? I intend to check out the EBL charger to know for sure.
When on EHU my SB is recieving just 0.1A which I assume is from the battery master that is supposed to supply 1.1A, I'll double check this tomorrow by measuring the rate directly at the battery master SB output. The SB has recently been at 12.49v by day and up to around 12.7v when on EHU before dropping back again, the battery is good though, just not getting a decent charge rate so I ran engine for a while to give it a boost, and it's not been started for 3 weeks anyway, the ground just turned black under the exhaust! 🙈 I was only getting a 0.25v voltage drop over the 7m between SB and LB so that seems quite acceptable.
I'm still figuring out what wiring changes and additions have been made to original as it's useful to know what the various extra fuses are for and if there is a better way? I have a 30A fuse at each end with a 20A fuse next to it at SB end, so from what you say I guess that's the original charge wire from EBL?
A recent look at the EBL99 wiring diagram was most useful to see how it originally worked! Am slowly sussing it out and almost there now. 👍
 
I ve got 2 Victron dc/dc chargers on the van,1 x 30a to charge the LB from alternator, and 1 x 9A to charge the SB from the LB while on EHU or solar,I’ve triggered the 9A dc/dc charger by the solar panel and battery monitor,the beauty of this set up,it acts as a trickle charger & a power supply for the electrics connected to the SB,ie it Powers the radio etc which other battery maintainers can’t do!
 
I remember someone looking at the wiring diagram for the EBL and saying there is no way it can be charging the starter battery when on EHU but mine does so without doubt. That part of the van is still OEM (one of the very few bits that is), mine has an 18amp Schaudt battery charger built into the EBL and I added a second Schaudt 18amp charger that just plugs into the back (front?) of the EBL.
I am not at the van for a few days so can’t get a pic but the fuse close to the battery in mine is either a 40amp or 50amp and the clip on piggy back fuse is small, less than 10 amps and possibly only a 5 amp. I find when my starter battery charge fails it is usually that 5am fuse. If your EBL charging has been done away with then not sure how they intended your to work. Is it possible to plug your mains charger into the Schaudt using the second battery charger connection port? May be too big on amps though to do that. I know some early EBL’s were only 10 or 15 amp chargers, later ones may well be higher than my twin 18amps. My EBL is a 101-2 so a different beast to yours
 
I ve got 2 Victron dc/dc chargers on the van,1 x 30a to charge the LB from alternator, and 1 x 9A to charge the SB from the LB while on EHU or solar,I’ve triggered the 9A dc/dc charger by the solar panel and battery monitor,the beauty of this set up,it acts as a trickle charger & a power supply for the electrics connected to the SB,ie it Powers the radio etc which other battery maintainers can’t do!
Nice setup. However ...

There is something you need to watch out for with this though .... the 9A B2B that charges the SB from the LB will raise the SB Voltage up of course.
When it increases sufficiently, it will hit the threshold for the 30A B2B to then switch on and start charging the LB from the SB, and that will stay active until the off-voltage threshold is met.
The result is that your 9A charge INTO the SB will end up being a 30A charge OUT OF the SB! Net difference... you will pull around 20A out the Starter Battery while the intention was to put 9A in, plus you will have all the energy losses in both B2Bs (each around 85% efficient). On mains you will just waste pennies, but on Solar, you will waste precious harvesting power.

You can get round this to a degree with the Victron Kit by using the remote input of the 30A B2B so it only comes on when the engine is running or maybe just the ignition/Acc line (you wouldn't want to use a trigger generated by the Solar Panel as the solar will still be active when you are driving).
 
I maybe wrong, but AFAIK the EBL99 will only charge the SB if it has wired to do so, and even then it is a small charge, whilst it will take the LB's up to higher voltage the SB won't go above 13v.
Our van has only a very small drop in LB when not in use, but the SB only goes a few weeks, but put it on EHU and the LB gets full charge, and SB gets very little, it's for this reason I still use my 'old' solar panel connected to SB, even thou I could use the EHU.
p.s. should note, the van is stored under cover, which is why I have to 'plug in' the old solar panel which is fixed to outside of shed.
 
If your EBL charging has been done away with then not sure how they intended your to work. Is it possible to plug your mains charger into the Schaudt using the second battery charger connection port? May be too big on amps though to do that. I know some early EBL’s were only 10 or 15 amp chargers, later ones may well be higher than my twin 18amps. My EBL is a 101-2 so a different beast to yours.
Yes, just had a better look and the EBL99 is designed to charge both batteries with it's 18A charger just like yours. It does have connections for an aux charger on block 7 so by moving the other 12.5A charger to there should charge the SB also. The fridge should also be from the EBL too but is not for some reason.
 
I took a look inside the EBL and confirmed that it's charger was well shot with about six components burnt out. So I connected my Zig X-70 charger to the EBL aux charger connections but it was still only charging LB. The EBL SB charger relay needs to be triggered to charge SB via pin 8 of block 3, but even directly connecting another charger to the original ones output connections would still not do that alone. I guess a mains powered relay would ideally remedy this to work as originally intended. Though simply manually linking the SB & LB via a switch would also have the same end result. It's handy to suss out how things actually work and being parked in a field for the foreseeable future It's just something extra to investigate to pass the time and learning a bit more too! So don't mind my thinking aloud here. Now why isn't the fridge wired to the EBL? 😄
There is a 70A SB cut off relay in the EBL that links SB and LB when engine is running triggered by D+.
 
Last edited:

Users who viewed this discussion (Total:0)

Back
Top