Little Help! - Leisure Battery

[LetsGo!]

Morning, we have two leisure batteries in our MH. On the control panel it shows how much of the battery is remaining, but i was wondering if this is for both batteries or just one battery?. Wasn't sure if this was for one battery and once it get to a certain percentage it would then switch to the second battery?!

Its just so we can try and figure out what we are working with if we dont have a hook up.

Thank you

 

[Ingwe]

I might be wrong but I expect your controller sees only one battery-so the 33% state of charge is for both batteries combined.
More knowledgable members will be along shortly, I imagine.

 

[PlacidoD]

It has got to be that it is reading both batteries - Yousa batteries are high quality but I am struggling to read details upside down. I am unsure if they are flooded lead-acid or gel or GSM. If they are flooded lead-acid you badly need to recharge them via solar or if in the UK atm by doing some driving or linking to an EHU.

If they are gel or GSM you are approaching danger territory and I would expect protective circuitry to switch them out. So more likely they are gel or GSM if you still have 12V working.

Does you Owner's Manual not tell you more on the subject?

 

[LithiumConvert]

I would normally expect the batteries to be connected together, but

The positives do not appear to be directly connected. The wires on each are different thickness, so not the same wire.

and the negative connection is very thin.

I would have it checked out.

But, to answer your question, put a voltmeter on both batteries in turn and see if the reading is the same.

 

[LetsGo!]

Appreciate the feedback, going back to the dealership to get an extra socket put in this week so will ask them to see what the say.

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[yorkiebar]

I would normally expect the batteries to be connected together, but

The positives do not appear to be directly connected. The wires on each are different thickness, so not the same wire.

and the negative connection is very thin.

I would have it checked out.

But, to answer your question, put a voltmeter on both batteries in turn and see if the reading is the same.

I imagine that there are additional wires from the top battery which are hidden from view due to the camera angle.

 

[LetsGo!]

Just plugged the Van in to charge the battery and it jumped up to 100% , disconnected the mains , put the TV and it dropped pretty much down to 60%?!. Totally new to working out the power restraints etc, but does this seem normal?. Also, when looking at the batteries, one has a green light showing which i assume is good to go whilst the other has no light, not sure if this mean its knackered?!

 

[berni109]

Your display is measuring the voltage from the batteries at the control unit then using an internal calculation like below to give you the %.

When you hookup the control unit shows 100% because that's measuring what the charger is putting into the batteries.
With your batteries being very low it will take many hours on charge to get them back to 100%

Tomorrow morning disconnect the hookup make sure everything is turned off then after half an hour switch the control panel on and look at the %.

If it's not 100% get your dealer to sort it out.

 

[PlacidoD]

I suspect that the 100% is in effect reading the EHU input via the charger. The 60% is something like the true state of charge with the draw of the TV (which will be quite high).

Your batteries are Yausa L36-100. They are flooded lead acid batteries. I think it is vital to leave the van on EHU for a good while.

L36-100 Yuasa Active Leisure Marine Battery 12V 100Ah

<h4>Yuasa</h4> <i>Advanced Engineering, Premium Quality, Unmatched Reliability</i> GS Yuasa located in Japan, all started in 1895 and is one of the biggest battery manufacturers in the world. Manufacturing batteries for the automotive, commercial and infrastructure markets. Yuasa Battery, Inc...

www.tayna.co.uk

I strongly suspect that at 36% one or both your batteries are cooked. It could be that one is dead and dragging the other one down. But others are far more expert than I am.

What van? What age? (And for that matter what dealer and where are you?) That info might help with diagnosis and suggestions as to what to do.

If it is going back to the dealer leave it on EHU until you set out would be my suggestion. Ideally take it off charge a couple of hours before you set out and take a photo of the reading then to show the dealer.

 

[GeoffnDee]

The battery not having the green charge indicator on it showing , will be faulty / drained of power.

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[LetsGo!]

Appreciate the feedback, van is still under warranty and any minor issues we have the dealership (Knowepark) have been really helpful. This is started when looking at potentially buying a portable power unit as a back up, alot of things to think about!

 

[autorouter]

It looks to me that originally the MH was fitted with a single leisure battery, in the lower position in your picture. The connections are quite substantial. Then someone added a second battery, fitted in the upper position in your picture. The two batteries are connected together in parallel (pos to pos, neg to neg) so the two batteries should act a one single big battery.

These batteries are 100Ah, so the pair should act like a single 200Ah battery.

As you say, one battery has a green indicator, and the other is black, so something is wrong somewhere. The first thing I would do is check the voltages of the two batteries right at the actual terminals, using a multimeter. Are you OK using a multimeter? Any cheap multimeter from a DIY store will be OK.

The voltages of the two batteries should be exactly equal to each other. If not, there is something wrong. I can see that there is an inline fuse on the link wire to the second battery. With two batteries spaced some way apart this is a good idea, but if placed right next to each other it is usually considered unnecessary. If that fuse has blown, the second battery will not be charged, and will not contribute any charge to the loads. If that has happened, the two battery voltages will be different from each other.

 

[pappajohn]

Other than the system seeing one large battery and power is pulled from both together The wires connecting the two batteries needs changing to the same thickness as the wires on the bottom battery.

 

[pappajohn]

Just noticed the white and red wire appears to go from the positive of the top battery to the negative of the bottom battery.
That is making the voltage 24v.
Positive to positive and negative to negative is 12v

 

[LithiumConvert]

I can see that there is an inline fuse on the link wire to the second battery.

Having looked at the picture on a better monitor, I think I agree with you.
The two wires to the fuse are different colours. (and confused me)

If that fuse has blown then autorouter is right. The top batttery wll not be contributing to the system.

As the wires are very thin, I would guess the fuse was too small to match the thin wiring and has blown.

As you say, one battery has a green indicator, and the other is black, so something is wrong somewhere

Confirms the theory about the blown fuse.

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The OP should charge both batteries seperately and then replace the fuse with thicker wires to connect the batteries together.
+ve and -ve wires both need replacing and the fuse is not necessary.

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[LetsGo!]

Thanks folks, have copied and pasted the above to take along with me. Will sound like i know what i'm talking about!

 

[autorouter]

Just plugged the Van in to charge the battery and it jumped up to 100% , disconnected the mains , put the TV and it dropped pretty much down to 60%?!. Totally new to working out the power restraints etc, but does this seem normal?.

The percentage charge figure is calculated from the voltage level of the batteries. That is only a good indication if the battery is not being charged and is not under any sort of load. That voltage is known as the 'resting voltage' and is a reasonable indication of the state of charge.

When being charged, a voltage higher than the resting voltage is applied by the charger, to force amps into the battery against the normal flow. That voltage definitely doesn't show the state of charge, even though the indicator will probably say it's 100%. Charging a flat battery takes time for the chemical reactions to happen, a couple of hours at least. The voltage will only tell you the charge level if it's the 'resting voltage', with no charging and no loads, after a rest of at least an hour.