is a switch needed for a compressor?

I don't know about anyone else here but it sounds like the switch may have saved the wiring and/or the compressor.

I wouldn't run one without a dedicated fuse and switch myself.

Ours is mounted in the rear and a 12V run capable of supplying 40 amps has been run to it via a 30 amp switch in the cabin and fused at 25 amps from a separate accessory fuse panel under the bonnet.

What compressor is it and is it portable or vehicle mounted?

Phil

ARB compressor specifications

Mark, you could do away with the switch and simply plug & unplug the Anderson to control the compressor. However you may cause some minor burn damage to the Anderson contacts by doing this.

Mark, There is a way to kill two birds with one stone. Use a circuit breaker such as in the photo below from ABR Sidewinder (Business Member).
The breaker can be operated as a switch and also protects against excess current.
These particular breakers have very convenient tunnel-type terminal connections not needing lugs. The terminals are fully shrouded and the breaker is easy to mount.
There are six of them in my Troopy.

Hi Mark,

I would think that if your melting switches maybe you need a relay rather than a bigger or better switch.

Most compressors should have a relay installed in them but I have seen a lot that do not despite what the sticker on or advertising brochure says.

Regards

Kurk

A lot of people under estimate the current drawn by compressors......even the current written on the plate or in the manual my be well and truly understated.

When compressor starts there will be a quite high surge...sometime twice or three times the running current......the current draw will then settle down, but as the pressure ( or head) the compressor pushes increases the current drawn increases.

I have one compressor that I baught from Aldi for diddley squat......similar to many others

It did not work out of the box...but that is a different issue....it was a silly wiring fault.

While I was fixing it A few things became apparrant.....

When I got it going the factory fitted 25 amp blade fuse blew a replacement 30 amp blew nearly as quickly.....so out with the clamp meter.....running at 30psi this thing was drawing over 35 amps....
The limit of the standard blade fuse format is about 30 amps and many blade fuse holders are only good for 20 amps.

Any way
These things draw a lot of current and the switch on and switch off surges can be realy hard on switch contacts.

They need to have a relay doing the switching...and a fairly solid one....most of them have a relay inside the housing if they have a switch on the body.

The factory relay in this unit was only a standard 30 amp horn relay..and a cheap one.

To cut a long story short...the unit has been given the treatment.
Heavier cable, a maxi blade fuse holder with a 40 amp fuse, a 60 amp horn relay and a remote control.

There was not enough room inside the case, so the relay was mounted on the base plate.

I have a remote control that can be plugged in so that I don't have to go all the way back to the compressor or the outlet to switch off in between checking pressures and moving to the next tyre.

I have a good second compressor for the less than $20 & few bits & time it cost me.

If ya switching any more than 10 amps, best to use a relay.
Don't forget to allow for the start up surge and the disconnection spike working the contacts hard.

As for using a circuit breaker as a switch.......not realy a good idea.....circuit breakers are not designed with frequently repeated operations in mind.
Keep using at a switch and it will get worn and not work too well as a circuit breaker.

cheers

Hi.
Wire your compressor as close as practical to the battery you will use,then run an air line to a convienent place to plug in your air hose. Use at least 8b@s cable through a relay that matches or is bigger than the current draw of your compressor. Then run some cable to a dash switch this can be lighter as it only switches the relay. Use good connectors and crimp with a little copper showing so you can run some solder down each crimp. No voltage drop and no switches to melt which will mean your compressor will run at full speed. Use a suitable fuse close to the battery.Also pays to use the starting battery for this exersize and keep the car running when pumping tyres as if for example its night and all lights and perhaps spotties are on your auxillary battery may not be charging at the time.My compressor draws 35 amps on its own.
cheers Graeme