Quick electrical question

[Terry]

I'm about to buy a 12v 6A/70W water pump on eBay. Am I right in assuming this is more current than the microswitch in the tap should handle, and that I'll need a relay? Anyone care to point me in the right direction as to what I should be searching for exactly?
Now I may well find the answer myself after a quick google, but somebody's bound to come across this problem in the future, and it wouldn't hurt for this forum to appear in their google search...

Here's the pump, if it helps: eBay listing

[David]

Hi Terry
Yes you are correct in thinking that the tap micro switch can not handle the current, they are rated at 0.6A and if using the pump that you are looking at then you would need a relay fitting, if you used a Whale universal (12v 8lpm 15psi) pump they work off a presure switch integral to the pump so when the tap is opened the water pressure drops and the pump will run.
An isolation switch should also be fitted so you can isolate the power supply to the pump, a simple pull on push off switch would be OK.

[Terry]

Thanks for that, David. I've just ordered a 4-pin type commonly used in cars. I assume I can connect the wires to the relay terminals with spade-type connectors?
A bit of reading on google suggests I should have a suitable fuse for the pump and a smaller fuse for the microswitch(es). As I'm planning to run all my wiring through blade-fuse blocks, I guess I'd just pull the fuse to isolate it...?

[David]

Hi yes crimp on spade terminals is fine I would still recomend an isolation switch just in case there is a problem it would be quicker to turn off the pump power supply than fumbling around trying to pull a fuse

[Terry]

...it would be quicker to turn off the pump power supply than fumbling around trying to pull a fuse

Yeah, good point. For the sake of a couple of quid, I'll go ahead and put an isolation switch in, near the fuse box. Thanks