split charge fuse keeps melting

[VWCamperfan]

I'm going to change my split charge relay for an old fashioned starter relay (the ones designed for inertia starter motors and are seperate). Should handle anything my alternator decides to chuck at it!

[Red Westie]

Indeed...it would! but a solenoid (relay) of this size takes quite a bit of switching itself (certainly a few amps) and I'm not sure wether I would be entirely happy using the relatively thin exciter wire off the alternator as the trigger feed for a heavy solenoid. As an example: Just think about how common it is for the spade connector on the starters to play up. Yes solenoids can handle hundreds of amps BUT as I said, take a fair few amps to operate.....one solution would be to use a relay to operate the solenoid but thats just getting a bit silly.
Martin

[djhammy]

HI Chaps as a footnote it took me the best part of 4 whole nights and big chunk of days to slow/trickle charge the battery. Now fully charged so hopefully things should be ok and i will try a 30 amp fuse. Only downside is i got a bit of acid from the breather tube on my new jeans which now have a nice series of holes on the leg. Mrs Hammy not happy at all!!

[djhammy]

HI guys i upgraded to a higher rated fuse and now it doesn't blow but the plastic simply melts after a long drive. I take it i need a better quality fuse as mentioned earlier in this thread. Had to chip it out of the relay.

[Red Westie]

A fuse is there to protect the circuit from overloading, trouble is..simply upping the fuse COULD MEAN instead of the fuse blowing a weaker part of the circuit is now going to overheat and melt. I have to warn you that the single biggest cause of motor vehicle fires today is down to poor after market wiring....things like retro fitted sound systems, spotlights and ooooer split charge circuits.....get the picture.
Martin

[camper]

Hi,

The split charge relay should be only making a connection between the positive output of the alternator
and the positive terminal of the leisure battery when your ignition switch is on. This allows the leisure battery to charge as the vehicle battery charges.

When the ignition is switched off, the relay contacts open breaking the connection between the alternator and the leisure battery.

Any lights or whatever connected to the leisure battery under these circumstances ONLY discharge the leisure battery and NOT the main vehicle battery.

Please advise me where this large fuse is and I may be able to advise you further.


Regards


Dave

But where do you take the ignition charge light connecton for the relay

[Mr Bean]

I would suggest you check the capacity of the wiring before you go any further. simply fitting a larger fuse in a circuit will move the function of the fuse over to the wire. So that in a fault condition the wire will heat up and could even catch fire. The fuse is intended to be the weak link in both the charging and utility circuits. A simple way of determining the adequacy of a circuit is to measure the volt drop between the source (battery) and drain (earth) under max load. Or in the charge scenario - the vokltage is measured between the alternator and the fully discharged battery. Anything over say 0.25V is bad news. All this is a load of hastle though so just make sure that wire is up to excess of 30 A and all the joints/connections are good and tight. Spade type connectors are notorious for feeble grip and once overheated are next to useless. Our first very primitive camper (Frod Thames van with mattress in back and primus stove) suffedred an internal wiring fire which only just beat the police in spoiling our night free camping at the Devils Punchbowl in Surrey back in the days of 405 line b/w TV and trouser turn ups.
Cheers
Wolfie
Rocker not Mod, Jack the lad not hippie.

[hixsy]

like i was told on here upgrade everything, relay/wire gauge/fuses holders. i went for 100 amp security in the end and ive got a monster sound system/stereo etc, its all been running fine for a few months now thanks to these guys here ! standard alternator too. cost about 50 quid total but worth it, its not hot and melting now !

[bigherb]

I'm going to change my split charge relay for an old fashioned starter relay (the ones designed for inertia starter motors and are seperate). Should handle anything my alternator decides to chuck at it!

No don't do it. Alternator warning circuits (Bosch) can only switch a maximum of four amps, remote starter solenoids can draw 11 amps to pull in and are not rated for continuous operation.