AGM cutoff at 10.5v, would this harm the battery?

[heliart]

See my other thread.
Turns out my HAB battery has been taken down to the 10.5v cutoff voltage of the EBK 3 times now within a couple of weeks.
Problem was due to a missing fuse on my new van.

Question is, the ElectroBlock has a 10.5v cut off, where it turns off all 12v systems if the voltage get's to that point.

I would never normally run an AGM down this low, and I'm now thinking that the battery might have sustained some longer term damage due to this?

Comments?

Extract from the ElekroBlock manual here - note, I was unable to get the 12v working at all without EHU, so assume the voltage was below the 11v threashold for a restart

Steve

 

[Lenny HB]

It will probably survive as the 10.5v will be under load we measure the state of a battery in the unloaded state which will be higher.

Only way to check is to run a discharge test on the battery.

 

[heliart]

Problem is, this is a brand new van. They forgot to replace the HAB fuse, so while driving the HAB was supplyng the fridge, so went down below 10.5v (the EBK cutoff) 3 times.
Dealer is next to useless, but I at least want them to change the battery for a new one.

 

[Lenny HB]

I think your van is wired similar to a Hymer and there is a 20 amp & 50 amp fuse by the starter battery if both of these had been left out it may cause the problem.
The 20 amp feeds the fridge via a relay in the EBL and the 50 amp is the fuse for split charging. Depends on how the fridge is wired on my van the fridge will only run off the hab battery it 12v has been selected manually, on previous vans it would select 12v & run off hab battery if no other form of energy is present.

If you get the dealer to change the battery try & get a Gel battery out of him they are far more reliable (will need a switch changing on the EBL).

 

[heliart]

I monitored this with the Smart Shunt. With fridge on Auto, Engine running - the fridge is taking over 15A from the HAB battery.
I now know how to work around this, forcing fridge onto gas for example. But, it does'nt alter the fact that the HAB battery had a deep discharge 3 times in 2 weeks. We will see what the dealer does (Travelworld), but I think as with so many things in life, after-sales is an after-thought.....
Will probably never buy from them again......

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[Lenny HB]

I monitored this with the Smart Shunt. With fridge on Auto, Engine running - the fridge is taking over 15A from the HAB battery.
I now know how to work around this, forcing fridge onto gas for example. But, it does'nt alter the fact that the HAB battery had a deep discharge 3 times in 2 weeks. We will see what the dealer does (Travelworld), but I think as with so many things in life, after-sales is an after-thought.....
Will probably never buy from them again......

Pull the AES fuse on the EBL then it will only work on 12v with the engine running.

 

[autorouter]

I'm not convinced that putting in that fuse has cleared all the faults. As Lenny HB says, pull out the AES fuse (the 20A one on the left, labelled 'AES 20A Sicherung nur bei AES Kuhlschrank'). With that fuse removed, does the fridge should work fine on 12V with the engine running? If it doesn't, there's a problem.

By the way, I think the fuse that was missing, which supplies current from the alternator/starter battery to the B2B, would be called the CAB fuse, not the HAB fuse. The hab fuse usually refers to the big fuse near the leisure battery that supplies the power for the EBL.

 

[heliart]

It was all down to the fuse.
It's all working now as expected. Just got back from a few days away. After fitting the Smartshunt I can see exactly what's going on.
Fridge set to auto - it runs on 12v with engine running. Stop engine, and the fridge switches to tank stop mode, then after 15 mins goes onto gas. On EHU it obviosuly switches to 240v.
To recap the problem, with the engine running the fridge was running on 12v, but this was coming from the HAB battery. There as no obvious indication of this, but with the Smartshunt you can see the current drain (in excess of 15A).

So if that CAB fuses blows it's maybe not so obvious until things start going flat.

Steve

 

[VXman]

Personally I would push for a new battery from the dealer just to be on the safe side. If they were aware/understood the problem and it wasn't your fault they should accept your request. If course it always depends on the dealer, some are less helpful than others.

 

[VXman]

....or at least register your concern with them so that if it becomes a problem in the future they cannot pretend they weren't aware.

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[heliart]

Yes, already done this. I had to have it fixed for this weekend (I was away for 3 days), and they never bothered calling me back last week so I removed their battery and bought a new one (pair actually) and have sent them the invoice for a new one and the fuses. Their customer care manager was very supportive and is looking at the case.

We'll see.

Steve

 

[Lenny HB]

Yes, already done this. I had to have it fixed for this weekend (I was away for 3 days), and they never bothered calling me back last week so I removed their battery and bought a new one (pair actually) and have sent them the invoice for a new one and the fuses. Their customer care manager was very supportive and is looking at the case.

We'll see.

Steve

Hope you bought Gels or standard LA and not crappy AGM's.

 

[heliart]

Lenny, is was like for like AGM. Cheap enough and got me going. The Varta 95AH was £165.
I will probably go solar and lithium next year, but want to get a good handle on my usage first.
I realy like CLs, and there's a lot that don't have EHU - which I like very much.
I need an inverter though, so going to live with it as is for a bit and see how I cope.

Cheers,

Steve

 

[Lenny HB]

You could have got a Gel for the same money and they are so much more reliable.

 

[VXman]

Hope you bought Gels or standard LA and not crappy AGM's.

Lenny's standard reply. Anyone would have thought he'd been dumped by an AGM battery at some point!

My AGM's have been working fine so far. We'll see in a couple of years if they still do. I've got three now I love them so much

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[headlight]

You could have got a Gel for the same money and they are so much more reliable.

Or a pair of lead acids with 4 year warranty for £80 each or £160 the pair.

 

[heliart]

I look on the bright side. Dealer wanted to charge me in excess of £400 for a 2nd AGM with fitting.....
Or £1600 including one solar panel - and all the wiring is already in the van, so dead simply you would think.

 

[Gizmouk]

I look on the bright side. Dealer wanted to charge me in excess of £400 for a 2nd AGM with fitting.....
Or £1600 including one solar panel - and all the wiring is already in the van, so dead simply you would think.

At least Dick Turpin wore a mask

 

[autorouter]

I need an inverter though, so going to live with it as is for a bit and see how I cope.

Gels generally are better than AGMs for leisure battery use, but they are not as tolerant of high amps discharge that you would have from an inverter. A couple of AGMs will have a good stab at supplying a medium-power inverter (800W - 1200W)

If you are thinking of an inverter, you should think of it as part of a whole system, with the batteries capable of feeding it, and the chargers (EHU, solar, alternator/B2B) capable of refilling the batteries as you want them to. Lithium batteries are very much better at high amps discharge, and can also recharge faster if you have the right chargers.

 

[heliart]

btw, just had a call from the dealer. They admitted their fault (how could they not), and paid for my new battery and fuses.

Cheers,

Steve

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