Ascot batteries

Hi, I've had the van for a year now and I'm gradually learning the ropes. Can anyone explain the battery system in my van. Two batteries under the drivers seat, both vehicle type and one leisure in the rear. I presume the one nearest the engine is the starter battery and the leisure battery feeds the habitation, but what is the purpose of the second vehicle battery? Does it get charged from the engine?Does the EHU charge it? Would appreciate any explainations. Trevor

If you have a look in your manual you should find a more detailed explanation or even better on the Ford Transit Forum (Mk7 Section) but put simply which I hope is of help-

The batteries under the drivers seat are the Vehicle Battery (Starter) and what Ford describe as an Auxilliary Battery (back up for memory items etc) and these were both fitted to the chassis by Ford. Both these are charged by the Vehicles charging system.
(On most Tranny models of this era original fitment I have seen was 1 Ford and 1 Varta branded battery)

The third battery is your Habitation Battery fitted by AS on conversion and this is charged by the Sargent System from EHU or Solar Panel if you have one fitted.

If you have a Solar Panel it is possible that there will be a battery master in the circuit which directs the charge to where its needed ie, tops up Habitation then the two Ford fitted batteries

AS were not very bright over describing the use of the Ford Auxilliary Battery indeed they were naughty on some models late Mk6s' and used it as a habitation battery

Roger,
I thought that the Aux battery fitted by Ford was coupled in parallel to the habitation battery fitted by A/S, thus in our case giving 60A/H (Ford) plus 80A/H A/S a total of 140A/H for habitation use. The Ford starter battery being isolated by the split charge relay unless the engine is running.
So do I have 140A/H to call on for habitation use or just 80A/H of A/S supplied habitation supply, 60A/H Aux battery under the seat for Ford auxilliary circuits and of course the Ford starter battery.
My system with Solar panel (80W) and Battery master has (touch wood) kept me happy with Amps to spare, but being and OLD Sparky and Kit Car builder, curiosity is driving me mad with the alternative battery combinations.
Sitting on a site in the Loire Valley (in the rain), pondereing what to do next.
Kind Regards Mike

I know from personal experience that the way that Ford wire up their twin batteries can vary - for example if a van has auto transmission they may be wired differently than if it has manual transmission (in an auto they will often be permanently wired together).

IMO the only easy way to answer these questions is to use a voltmeter connected to each battery in turn. Switch on the charger and see which batteries rise in voltage. Start the engine and see which batteries rise in voltage. You may need to disconnect or cover over the solar panel temporarily to prevent that from causing any confusion.

I would hope to find that the leisure battery is ~not~ connected in parallel with the vehicle aux battery, because these should (or might at some point during the life of the vehicle) be different types of battery with different charge/discharge characteristics.

I am pretty certain ours is not connected in parallel with the leisure battery as I would have seen this when ditching the little 85ah job to put a proper sized 150AHr leisure battery in.  That said our van didnt have the diesel heater which I suspect AS might have connected to the Aux Battery

Agree with mojo

In my Wilton the Ford and AS leisure/auxiliary batteries were definitely connected in parallel.

Peter

Thanks all for showing an interest.It seems their is disagreement on this subject.Looks like I need to get hold of a Voltmeter as Mojo suggests. Will report on progress. Thanks again

helpdriver wrote:It seems their is disagreement on this subject.

It's not so much that there is disagreement. The fact is that A-S change lots of things - such as the location of batteries, the make/model of power controller and the way they wire them up - during the production life of any of their models. So what's true in one Ascot may not necessarily be true in another...

Hi All, Have checked battery charges with a Multimeter and found that the EHU charger seems to supply charge to the rear leisure and vehicle battery nearest the pedals only.The engine seems to charge both vehicle batteries. Have been informed by Ford that the rear of the two vehicle batteries is always the main starter unit.

Yes - exactly as my Wilton was, you do have two leisure batteries connected in parallel that support both Ford auxiliary apparatus and the AS habitation equipment.

Peter

Hi all,

Just got the internet here in France and pondering how to test whether the batteries are in parallel on the Ford Mk7 chassis, I came up with a simple solution :- Just put one light on and disconnect the leisure battery in the habitation part of the motorhome (not the one under the drivers seat) then if the light stays on they are in parallel -- if it goes out then your leisure battery is on it own. Simples and no meter needed.

PS after 4 days of horrendous storms the sun is at last shining, hope it stays that way fro our last 6 days away.

Mike

mike wrote:Hi all,

Just got the internet here in France and pondering how to test whether the batteries are in parallel on the Ford Mk7 chassis, I came up with a simple solution :- Just put one light on and disconnect the leisure battery in the habitation part of the motorhome (not the one under the drivers seat) then if the light stays on they are in parallel -- if it goes out then your leisure battery is on it own. Simples and no meter needed.

Yes but of course you must be disconnected from the mains else the PSU will power the light.

Peter

Good point Peter.
I have never used the mains charger unit in 5 years other than have it tested during habitation check, my solar panel keeps the batteries topped up. So I and I suspect other would have missed your valuable comment re the mains power unit.
Thanks Mike

mike wrote:Good point Peter.
I have never used the mains charger unit in 5 years other than have it tested during habitation check, my solar panel keeps the batteries topped up. So I and I suspect other would have missed your valuable comment re the mains power unit.
Thanks Mike

Actually on a reasonably bright day the solar panel would also keep a bulb lit, if you can't disconnect it easily just put all the lights on for the test.

Peter

Just to clarify in my van the batteries under the drivers seat are both vehicle batteries of the same type.It seems in some vans the aux is a leisure battery.

helpdriver wrote:Just to clarify in my van the batteries under the drivers seat are both vehicle batteries of the same type.It seems in some vans the aux is a leisure battery.

Generally I think you'll find that the original aux battery will always have been a vehicle type battery - AFAIK they are all fitted by Ford before they leave the factory. If you find an Aux that's a leisure battery then it has ~probably~ been replaced during the life of the vehicle.

Incidentally, Ford didn't quite give you the full picture - at least for the older vans. The exception to their rule is if the transmission is an auto then both batteries will be starter batteries, as they will ~probably~ be wired together all the time.

helpdriver wrote:Just to clarify in my van the batteries under the drivers seat are both vehicle batteries of the same type.It seems in some vans the aux is a leisure battery.

Hi helpdriver

Are you now happy you have enough information about your battery installation or are you still unclear? If you have further questions then photographs of your complete battery installation (you are a contortionist) and either a picture of the label on each or a note of the specification will help me give a very detailed explanation of what you have and how it all works.

Peter