toggle switch question

He wants center off so he can turn the fan off.

why does he need center off?
bumpy

Bobbo wrote:

beemerphile1 wrote:
SPST and wire it in parallel with the thermostat.

That will allow you to turn on the fan even if the thermostat didn't, but it won't allow you to turn the fan off if the thermostat has it on.

You need a 3 position switch....

You are correct, I should learn to read more thoroughly. I thought he wanted to choose between thermostat control or manual on. I neglected to note that he also wants to be able to turn it off.

So I change my answer to SPDT. The DPDT may be easier to find and will also work.

PM answered.

Bobbo wrote:
No problem. Glad I could be of help. The folks on here have helped me immeasurably in the past.

stand by for a pm

No problem. Glad I could be of help. The folks on here have helped me immeasurably in the past.

The switch pictured is dc rated. Thanks Bobbo you have been a great deal of help! It's people like you in this forum that has increased my knowledge and made the rv tech problems in my life much easier to tackle. thanks to everyone. RVNET ROCKS!

I think we are getting confused on terminology.

SPST - also known as ON/OFF switch, has only 2 contacts

SPDT (center off) - (not mentioned by this name yet) is the 3 position switch I mentioned before, having 3 contacts, ON/OFF/ON. This is also available without the CENTER OFF but is not what the OP wants.

DPDT (center off) - just like the SPDT switch, but has 6 contacts and switches both the HOT and the GROUND, think of this like the ATS on your RV's AC system. This is also available without the CENTER OFF which is often used to reverse polarity, like on a ceiling fan to make it turn backward. Wire the corners in an "X" and hook the motor wires to one end only, you get current flow one direction, then switch it to the opposite flow direction.

The SPST switch will only turn the fan on regardless of the thermostat. It will not turn the fan off if the thermostat has it turned on.

The SPDT will do both.

The DPDT will do both, and in addition will break both wires, which is not necessary.

The switch pictured above is perfect as long as it is DC rated. If it is only AC rated, it will work for a while before it fails. It does APPEAR to be 12v DC rated from what I can see.

You need a 3 position switch. But be sure it is rated for DC.

Position 1 has the thermostat controlling the fan.

Position 2 is off, nothing runs.

Position 3 has the fan running, even if the thermostat is off.

Here is the switch i am wanting to use to achieve the above positions

my apologies