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+-- Thread: Fan Control Wiring Help Please (/showthread.php?tid=7345454)
Fan Control Wiring Help Please - jteneyck - 01-04-2019
I've replaced the variable speed fan control on our wood stove at least 3 times. The little unit is housed in the fan unit right under the front of the stove, and the heat it's subjected to causes an early death. I even put a thin piece of fiber insulation behind it the last time I replaced it, trying to shield it from the heat, but it still died in less than a year. So now I'm going to install a stand alone unit on the wall next to the woodstove where it won't be exposed to heat.
I bought a unit from KB Electronics, Model KBWC-16LK, as shown here. The wiring diagram is the bottom left one on page 2. I thought I was buying a two wire module, as shown in the top left drawing on page 2, but what I've got is the 3 wire one. The third wire (red) on the unit I have is connected to an "auxiliary" load. But I don't have an auxiliary load, just the fan, so should I just cap off that lead or should I connect it to the neutral wire coming back from the fan?
Thanks.
John
RE: Fan Control Wiring Help Please - TDKPE - 01-04-2019
Looks to me that connecting that Aux lead to the neutral would simply create a dead short and probably ruin the unit the first time the relay closed. Just cap it off and call it good, unless you want to add an indicator light to show the fan is running.
It has a limited ability to drive a load, so a high impedance load like a small light or the coil of a power relay (for some other big load) would be about all it can handle. There's probably a published limit on the load you can put on it, either total load, or separately for the triac controlled load and the aux load.
Edit: Looks like that model has a 6A max load, which includes the aux lead, with no separate rating for the aux lead.
RE: Fan Control Wiring Help Please - jteneyck - 01-04-2019
(01-04-2019, 11:00 AM)TDKPE Wrote: Looks to me that connecting that Aux lead to the neutral would simply create a dead short and probably ruin the unit the first time the relay closed. Just cap it off and call it good, unless you want to add an indicator light to show the fan is running.
It has a limited ability to drive a load, so a high impedance load like a small light or the coil of a power relay (for some other big load) would be about all it can handle. There's probably a published limit on the load you can put on it, either total load, or separately for the triac controlled load and the aux load.
Edit: Looks like that model has a 6A max load, which includes the aux lead, with no separate rating for the aux lead.
Thanks very much. That makes sense. I don't need an indicator light, you can hear the fan when it's running, so I'll cap off that lead.
You are the master of all things electrical, and if not all then at least all I'll ever need to be concerned with.
John