Rodnut - Four wire trim/tilt pump motor ?

[boscoe99]

Is the thermoswitch in the pump motor normally open or normally closed? I be guessing normally closed but... Yamaha does not say.

[99yam40]

I am trying to understand how a normally open thermoswitch could allow the T&T motor to run

[boscoe99]

I don't think that it will. But there are times when stuff is not as it appears to be. Just looking for confirmation before I put my two cents worth out there.

It is not in the power feed circuit. It is in the ground side of the relay.

The Yamaha diagram shows the switch as being open. Contrary to the position that I would expect it to be in normally. Most manufacturer's drawings depict a part in its normal state, not in the abnormal state. IME anyway.

But it is a Yamaha diagram so...

[ausnoelm]

Not too sure I am reading this right, BUT, it is very common to show switches in the open position in wiring diagrams, simply because of the symbol used, in the closed position it kind of just looks like nothing is there (if you get what I mean) some diagrams show the switch in a circle, so it is not missed, but this is not really common, but I have seen it.

[99yam40]

It is not in the power feed circuit. It is in the ground side of the relay.

The Yamaha diagram shows the switch as being open. Contrary to the position that I would expect it to be in normally. Most manufacturer's drawings depict a part in its normal state, not in the abnormal state. IME anyway.


But it is a Yamaha diagram so...

Ok I see how this might work if it is con*****ing the ground on relay and not in the power itself.
I agree prints usually show what a circuit is doing in the de energized state.

still not sure how the relay could work without a ground in the normal condition if it is NO
can you show print you are talking about

[rodbolt17]

a tad o common sense will help.
the motor thermoswitch is normally closed.
it will open to keep the motor from frying itself in the event of abnormal current draw or motor overheat due to running in a stalled condition.
that is it's sole function.

[boscoe99]

a tad o common sense will help.
the motor thermoswitch is normally closed.
it will open to keep the motor from frying itself in the event of abnormal current draw or motor overheat due to running in a stalled condition.
that is it's sole function.

Thanks.

My uncommon sense was telling me that the Yamaha diagram was misleading. The illustration for the thermoswitch is depicted in the open position. Or as Yamaha says, the "off" position. Not the closed position as one (me) would suspect.

[99yam40]

long ago I had a problem looking at schematics and logic ladders on programs.
understanding it was shown deenergized ,but when powered up a lot of it changed states.

I believe like you Yamaha just messed up on the one you were looking at