[Crystal-clear]

Ok here we go with a DIY question .. 
I have a handyman coming over to sort the main van tomorrow. He's going to remove everything and lay down the rubberised floor which is waterproof and drill some holes in case there's a water log so it doesn't go into the cabin no chance anymore.
But I was going to ask him to rewire and I noticed the very thick wire cable running from the battery to the battery in the van. Is this cable better as a conductor than the thin cable? I was going to ask him to run that through and remove the Old thin cable . Am I right or does it not matter? I was thinking thicker so a lot more material then thin stuff which can corrode faster on the connections.

[Spruce]

Ok here we go with a DIY question .. 
I have a handyman coming over to sort the main van tomorrow. He's going to remove everything and lay down the rubberised floor which is waterproof and drill some holes in case there's a water log so it doesn't go into the cabin no chance anymore.
But I was going to ask him to rewire and I noticed the very thick wire cable running from the battery to the battery in the van. Is this cable better as a conductor than the thin cable? I was going to ask him to run that through and remove the Old thin cable . Am I right or does it not matter? I was thinking thicker so a lot more material then thin stuff which can corrode faster on the connections.

Battery to battery cables should be 'thick' as they need to carry a heavy load.  The old van had 70amp (10mm˛) cables and the current van I increased the size to 110 amp (16mm˛).

Somewhere in the system you should have a split charge relay or voltage sensing relay to act as a battery isolator. If you have a split charge relay then there is a possibility that there will be a thin wire going to either the van's alternator or the ignition switch to activate the relay only when the van's engine is running.

As a comparison, your normal 3 core 13 amp cable on an extension  drum is 2.5mm˛.

This cable has to carry a heavy load. Yesterday my van stood in one place all day . When I started the engine the van's alternator was pushing 40amps into my leisure battery for quite sometime before it started dropping back.

.

 

[Crystal-clear]

Ok here we go with a DIY question .. 
I have a handyman coming over to sort the main van tomorrow. He's going to remove everything and lay down the rubberised floor which is waterproof and drill some holes in case there's a water log so it doesn't go into the cabin no chance anymore.
But I was going to ask him to rewire and I noticed the very thick wire cable running from the battery to the battery in the van. Is this cable better as a conductor than the thin cable? I was going to ask him to run that through and remove the Old thin cable . Am I right or does it not matter? I was thinking thicker so a lot more material then thin stuff which can corrode faster on the connections.

Battery to battery cables should be 'thick' as they need to carry a heavy load.  The old van had 70amp (10mm˛) cables and the current van I increased the size to 110 amp (16mm˛).

Somewhere in the system you should have a split charge relay or voltage sensing relay to act as a battery isolator. If you have a split charge relay then there is a possibility that there will be a thin wire going to either the van's alternator or the ignition switch to activate the relay only when the van's engine is running.

As a comparison, your normal 3 core 13 amp cable on an extension  drum is 2.5mm˛.

This cable has to carry a heavy load. Yesterday my van stood in one place all day . When I started the engine the van's alternator was pushing 40amps into the battery for quite sometime before it started dropping back.

.

Hi yes there is a split relay which accommodate the small cables is it ok to cut down the big cable to fit into that?

[Spruce]

Ok here we go with a DIY question .. 
I have a handyman coming over to sort the main van tomorrow. He's going to remove everything and lay down the rubberised floor which is waterproof and drill some holes in case there's a water log so it doesn't go into the cabin no chance anymore.
But I was going to ask him to rewire and I noticed the very thick wire cable running from the battery to the battery in the van. Is this cable better as a conductor than the thin cable? I was going to ask him to run that through and remove the Old thin cable . Am I right or does it not matter? I was thinking thicker so a lot more material then thin stuff which can corrode faster on the connections.

Battery to battery cables should be 'thick' as they need to carry a heavy load.  The old van had 70amp (10mm˛) cables and the current van I increased the size to 110 amp (16mm˛).

Somewhere in the system you should have a split charge relay or voltage sensing relay to act as a battery isolator. If you have a split charge relay then there is a possibility that there will be a thin wire going to either the van's alternator or the ignition switch to activate the relay only when the van's engine is running.

As a comparison, your normal 3 core 13 amp cable on an extension  drum is 2.5mm˛.

This cable has to carry a heavy load. Yesterday my van stood in one place all day . When I started the engine the van's alternator was pushing 40amps into the battery for quite sometime before it started dropping back.

.

Hi yes there is a split relay which accommodate the small cables is it ok to cut down the big cable to fit into that?

I think you need to put up a photo of the cables with the split charge relay so we can see what you mean.

If you have a 70 amp cable and a 30 amp split charge relay then yes you can reduce the cable size going into the relay. But the wiring from the relay to your leisure battery needs to be able to carry 30 amps. 

Inline fuses. If you have a 70 amp battery cable running to your 30amp relay (SCR) then the inline fuse at the van battery needs to be a maximum of 30 amp, preferrably fractionally lower. The inline fuse just before the leisure battery also needs to be a maximum of 30 amps.

[Crystal-clear]

Ok here we go with a DIY question .. 
I have a handyman coming over to sort the main van tomorrow. He's going to remove everything and lay down the rubberised floor which is waterproof and drill some holes in case there's a water log so it doesn't go into the cabin no chance anymore.
But I was going to ask him to rewire and I noticed the very thick wire cable running from the battery to the battery in the van. Is this cable better as a conductor than the thin cable? I was going to ask him to run that through and remove the Old thin cable . Am I right or does it not matter? I was thinking thicker so a lot more material then thin stuff which can corrode faster on the connections.

Battery to battery cables should be 'thick' as they need to carry a heavy load.  The old van had 70amp (10mm˛) cables and the current van I increased the size to 110 amp (16mm˛).

Somewhere in the system you should have a split charge relay or voltage sensing relay to act as a battery isolator. If you have a split charge relay then there is a possibility that there will be a thin wire going to either the van's alternator or the ignition switch to activate the relay only when the van's engine is running.

As a comparison, your normal 3 core 13 amp cable on an extension  drum is 2.5mm˛.

This cable has to carry a heavy load. Yesterday my van stood in one place all day . When I started the engine the van's alternator was pushing 40amps into the battery for quite sometime before it started dropping back.

.

Hi yes there is a split relay which accommodate the small cables is it ok to cut down the big cable to fit into that?

I think you need to put up a photo of the cables with the split charge relay so we can see what you mean.

If you have a 70 amp cable and a 30 amp split charge relay then yes you can reduce the cable size going into the relay. But the wiring from the relay to your leisure battery needs to be able to carry 30 amps. 

Inline fuses. If you have a 70 amp battery cable running to your 30amp relay (SCR) then the inline fuse at the van battery needs to be a maximum of 30 amp, preferrably fractionally lower. The inline fuse just before the leisure battery also needs to be a maximum of 30 amps.

Cheers unfortunately this is Chinese to me I'm going to forward this off to the handyman. Thank you so much

[bravo20]

Worried about the 'handyman' bit, think you need an auto electrician.