Leisure battery set up

[garethej87]

Hello all

I am new to the bongo world and I'm trying to figure out how my leisure battery is set up? Has anyone seen this before and can explain how it works. It looks like the leisure battery runs strait to the rear fuse board.

[garethej87]

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[garethej87]

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[g8dhe]

The units towards the rear are the Electrical Hook Up (EHU) switching and a 12v supply which will charge the LB when your on EHU as well as run the 12v systems in the van.
I can't see a Split Charge Relay under the bonnet, but it may be hidden, this will allow the alternator to charge the LB when mobile so that your LB is fully charged when you arrive and stop, most setups have this as well as the EHU and charger in the rear.

[garethej87]

The units towards the rear are the Electrical Hook Up (EHU) switching and a 12v supply which will charge the LB when your on EHU as well as run the 12v systems in the van.
I can't see a Split Charge Relay under the bonnet, but it may be hidden, this will allow the alternator to charge the LB when mobile so that your LB is fully charged when you arrive and stop, most setups have this as well as the EHU and charger in the rear.

Thank you for the reply. I can't seem to find a split charger. The positive cable seems to run straight to the fuse board. And the SB cables runs to the fuses by the steering wheel. If I was to add a split charger, were could I join it? Sorry I know very little about it.

[garethej87]

Could I just literally just add this to the set up?

[g8dhe]

The normal way of adding a Split Charge Relay is between the +ve of the SB to the +ve of the LB both under the bonnet;

I would suggest you check thoroughly for any additional connections to the SB +ve before adding additional relays, however there have been some convertors who didn't add them.

[garethej87]

The normal way of adding a Split Charge Relay is between the +ve of the SB to the +ve of the LB both under the bonnet;
Leisure_battery_configuration.png
I would suggest you check thoroughly for any additional connections to the SB +ve before adding additional relays, however there have been some convertors who didn't add them.

Thank you for this. I couldn't get my head around how it works. But I get it now! I will look later and follow the cables. Make sure there isn't a relay. If I don't find one i will add one on. Really appreciate the help

[garethej87]

The normal way of adding a Split Charge Relay is between the +ve of the SB to the +ve of the LB both under the bonnet;
Leisure_battery_configuration.png
I would suggest you check thoroughly for any additional connections to the SB +ve before adding additional relays, however there have been some convertors who didn't add them.

One last sily question sorry. I disconnected my SB and left the leisure battery connected. Just out of interest I turned the ignition on and it allowed me to start the van. I'm I right in saying this means the battery's are not separate.

[garethej87]

The normal way of adding a Split Charge Relay is between the +ve of the SB to the +ve of the LB both under the bonnet;
Leisure_battery_configuration.png
I would suggest you check thoroughly for any additional connections to the SB +ve before adding additional relays, however there have been some convertors who didn't add them.

One last sily question sorry. I disconnected my SB and left the leisure battery connected. Just out of interest I turned the ignition on and it allowed me to start the van. I'm I right in saying this means the battery's are not separate.

So this is what it looks like behind the fuses board and going into the back EHU. Does this look right?

[g8dhe]

Right NO that isn't right BUT not unexpected ..... originally the Split Charge Relays ONLY operated when the voltage on the SB was higher than the operating level i.e. engine running, however the designs changed as more people used them in our sort of role, also it was cheaper to make, hence the relays would operate if EITHER battery was above the trigger voltage of around 13.6 volts, this means that if you disconnect the SB but leave the LB connected and its on charge then the relay will operate and the vehicle can be started from the LB or at least an attempt made, this can be a bad idea as the LB's aren't designed to give that sort of amperage for the starter motor, most will normally drop down rapidly and starting will stop!

As to the wiring behind the fuse panel, its not sensible to comment as I can't really see what has been done and its easy to mislead you, it needs drawing out to be certain!

[garethej87]

Right NO that isn't right BUT not unexpected ..... originally the Split Charge Relays ONLY operated when the voltage on the SB was higher than the operating level i.e. engine running, however the designs changed as more people used them in our sort of role, also it was cheaper to make, hence the relays would operate if EITHER battery was above the trigger voltage of around 13.6 volts, this means that if you disconnect the SB but leave the LB connected and its on charge then the relay will operate and the vehicle can be started from the LB or at least an attempt made, this can be a bad idea as the LB's aren't designed to give that sort of amperage for the starter motor, most will normally drop down rapidly and starting will stop!

As to the wiring behind the fuse panel, its not sensible to comment as I can't really see what has been done and its easy to mislead you, it needs drawing out to be certain!

Thank you again for your help! I will need to find someone to look at it I think as I'm not sure what it supposed to be set up like. There is definitely no relay in there as both battery's are linked direct via the positive with no relay between. For some reason the positive that should go directly to the EHU in the back has been split into 2 cables ( another red positive added to it with insulation tape ) one going into the fuse board and the other going to the EHU. Then they join again at the EHU. I will check on the Berwickshire bongo Facebook and see if there is anyone local that could look at it. Thanks again for the quick response and help

[g8dhe]

Its quite possible that the two +ve connections running to the rear of the van might just in affect be in parallel, running two smaller cables is often a lot easier than trying to run one thicker cable thru the vehicle.