mystery fan switch wiring

go

black

have

still

position.

Maybe you are using a high impedance meter (DVM) for these measurements? Repeat using a test rig that passes current through to contacts and measure volt drop. Otherwise what you describe seems to be a standard way of implementing 3 speeds plus off on a small fan. I expect the switch terminal with the white wire is simpley used for inter-connection purposes only. The capacitors are connected in turn for low and medium speeds and placed in parallel for the top speed. A variant on this which you don't seem to have is to connect power directly to the motor for the top speed.

Bob

yes I use DVM. What is that test rig and why does it matter? U say this is standard. Please explain. When the switch is disconnected and I join either the black or white to the caps nothing happens. If the switch connects the white to the caps, then the common will not get connected to the fan. If the switch connects the black to the caps then why is white connected to switch? The fan does not work and I want to know if it is the switch or motor. What other connections can I try to see if the fan works. Connect the white to black?? Just kidding

paul

wire(white)

Common

and

all

no

circuit

placed

either

the

switch?

What

OK New information. You did not say the fan is faulty. Measure the dc resistance of the motor alone. Expect a few 10s of ohms. If this is OK, put motor in series with a 100w light bulb (to limit the current) and connect across the ac supply. No switch, no caps. Motor should turn.

Add one of the capacitors in series. Motor should turn but slower. Note that there will only be a speed change if the motor is loaded ie by the fan. Speed change is effected by the reactance iof the capacitor dropping the voltage available to the fan and the loaded fan allows the motor to slip and hence run slower.

Test the other capacitor similarly. If this is all OK then suspect the switch. These switches are not usually standard 1p 3w, so you might find it difficult to replace.

hth

Bob

Motor case will not open. Screws removed, but casing does not budge, it does free spin by hand. 7 wires going into the motor casing, so I can't test. Unless I could find a fan schematic, but I can find nothing on manu: "A.C. Ceiling fan". Putting voltage to the fan side of the caps does nothing. When switch is wired to fan then the fan hums in all on positions. Understanding the wires to the fan should allow me to evaluate what the switch should do, no?

and

and

terminals

with

is

is

implementing

If

to

does

When

Understanding

do,

Paul, I despair of people like you. Every reply I give, you come back with new information. Sorry mate - sort it out yourself - you have all the information Life is too short for me to wait until the whole story comes out.

Bob

sorry, I should have asked you what exactly you needed to know. Which is kinda hard to do before you know what my question will be.

thanks, but done that been there. The only schematic there does not indicate how the switch works electrically. So, of no use to me.