Star Delta control circuit.

[HOJ]

I have aquired an SCM L'invicible 2000 16" planer thicknesser, the contactor is shot, and has been hot wired,
I am trying to rationalise the control circuit, which along with the usual stop/start function, has a rotary
switch, in order to switch the motor from: "O", through Star, to Delta.

The rotary switch has a pair of wires back to the contactor, giving me a normally closed switch position at "O"
which would seem to act as an interlock on the Start circuit, am I right in the assumption that
this is designed so that when the starter is actuated it will only engage if the rotary switch is in the "O" position.

I have drawn out how I see it working, does this look right?



Paul

 

[HOJ]

Result, all up and running, its been in storage for a few years but has cleaned up well so far, need to get the blocks
out to clean them, not sure how to do that, as yet.

Machine weighs in at 620Kg and is incredibly quiet running (for those that are interested) not had chance to machine
any wood as yet, blades are dull, off to be sharpened, also looking out for a manual if anyone finds one.

 

[Myfordman]

Only just seen this but is sounds that you are sorted. One temptation when debugging contactor circuits is to manually operate the contactors to work out what does what but NEVER EVER do this with a star delta system as it is possible to put a dead short across all three phases by doing so. The interlock must be allowed to do its job which apart from starting the motor, must prevent both contactors operating at the same time.
Must be quite beast. Star delta switching does not tend to get used below 5hp in my experience.

Good Luck

Bob

 

[HOJ]

Bob,

Not actually got to the motor as yet, so not sure the HP rating, and cannot find any info on the web about it.

This machine only has a single, Triple pole contactor, the Star/Delta switch over is done manually
with the 3 position rotary switch, so no chance of shorting out contactors.

Paul