Relay question: Correct me if I'm wrong...

[Boy914]

Hi.

Looking at the water pump article on today's front page got me thinking: Can't you just clip a molex connector and wire it to a relay to get the same results? That's what I got out of the article in the tips and tricks section...

Thanks,
Rick

[The Overclocker]

yeh, you are wrong, the highest voltage made on the 4 pin molex connectors is 12 volts DV, the power the pump needs is 110 or 230 AC...

[Boy914]

I think you misunderstood: from what I understand of the relay, the 12V power merely triggers the relay to close the connection to the wall outlet. The pump still gets power from the wall plug (120V), the relay just acts as a switch that turns on when the 12V wires have power.

This is based on my assumptions on the workings of a relay. I could be dead wrong. Please let me know if I am...

[Voodoo Rufus]

You can hook up a molex to 110/230 AC. I believe that whether it works or not depends on the total power going through the molex in watts. I know that with about 30 Amps on 7.2V in R/C cars will just about melt the connectors, but that is over 200W. Hooking a relay to a pump and a molex should be fine since pumps pull around 10W

[The Overclocker]

oops, sorry, i suppose i should have read the article throughly (i just look at the pritty pictures) yes, connecting it up to the molex will work

[ptcg]

I have a 120VAC relay with a 12VDC coil that triggers the refrigerator to run when the PC is turned on... I just wired an extra one of the small fan connectors to the coil & I have the relay plugged into an unused fan connector on my mobo.. works fine.