Issues with voltage drop and melting wires

Submitted: Wednesday, Apr 17, 2013 at 03:13
ThreadID: 101742 Views:8393 Replies:7 FollowUps:48
This Thread has been Archived
Voltage drop:
Our compressor is mounted way down the back of the car, in a void beside the drawers and controlled with a switch in the center console. On our recent Simpson trip the compressor became unreliable and only worked intermittently. Sometimes it worked and if it didn't then you flicked the switch until it started. It had just been relocated before trip and the cable to the fridge was used.

Why did it play up? Voltage drop was the answer. Okay for the fridges but too small for the fridges PLUS the compressor.

Don't just add to an existing circuit. Add up ALL the load and use a new run if needed.

Solution:
When we got home a new heavier cable was run just for the compressor all the way from the battery, through the switch on the console and Compressor works a treat now. The new cabling also included a brand new 30 amp per circuit fuse box for all the 4WD accessories instead of a rather suspicious second hand one that the auto sparky had used. It has spoofy bright red leds to indicate a blown fuse. And is labelled!!!!

Melting cabling:
Yesterday on this forum I came across a bloke with a 15 amp switch in a 35 amp compressor circuit. The switch had melted and it's no wonder why. But the fuse was okay. Luckily no fire.

A few weeks back there was a fire in a mates car on a group trip. It was a professionally installed additional battery in the ute tray with the cabling run through a hole drilled in the tray body work. Yes, a good grommet was used. The body of a ute flexes independently of the cabin and thus over time the edge of the hole wore through the large grommet and then the insulation of the big thick positive battery cable putting the positive directly to earth. Bloody ouch. Fires everywhere and even a brake line to the master cylinder was melted. And all professionally installed.

Solution:
Be careful selecting the correct cable and where you choose to run the cable. Go up a size to be safe. Allow for flexing and protection against sharp edges, shorting and rats/mice eating the insulation.

Phil
Back Expand Un-Read 1 Moderator

Sponsored Links