humidifier

I need some help. I have setup a large humidifier with a controller to start the humidifier when the humidity reaches a setpoint.   Sometimes when the setpoint is reached it attempts to start the fan but the fan is acting like it's pulling to much current causing the controller to discharge and the relay to open. The humidifier begins to start, stop, start, stop...... You get the point. I think I need to add a capacitor to the primary side of the step down transformer so that when the relay closes it fills the voltage drop so that the components on the secondary side maintain power. Help please. I have uploaded the circuit.

You can't add a cap - that's an AC circuit (it doesn't store charge like a DC capacitor).

Besides, that transformer has nothing to do with the fan's supply - it merely turns on the relay that connects the fan across the raw AC supply.

Either your AC feed is too small & too long, or you have a faulty fan - maybe seizing bearings, or a blown internal (starting) capacitor or faulty centripetal switch (depending on the motor type).

What do you mean by AC feed too small and too long? Frequency and period of sinewave?

Is there something in the design of the circuit? This is my design am I missing something that may be needed? It's a simple circuit. I thought about the capacitors on the humidifier being bad, but why would that cause the rest of the circuit to loop power on, off, on off?

Agreed - simple circuit. It looks fine.   

Without knowing more about the HC-100 etc - which seems irrelevant anyhow - I suspect an AC issue.

Does the fan run ok on raw AC - ie, shorting together R1's switched AC terminals 4 & 2?

Does R1 switch correctly with the fan disconnected?


PS - "too long" means to thin a gauge for the current required hence current limiting or too big a voltage drop. Frequency (period) will not change.

I will try and see if I can get the issue to occur on raw AX.
R1 does switch correctly when humidifier is disconnected.
I understand now. I believe the guage wire is correct however, it may be too long of cable. I do remember it was pretty lengthy. I will check the out put at the fan when R1 is closed tomorrow. This is at work, lol. Thoughts?

Yep - try bridging R1 first. Then compare to a shorter AC line if needed.

If it's a big load, then the long run could well be the issue. And if it's a fan and compressor etc...