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Discussion Starter · #1 ·
Does anyone have an actual picture of how diodes are mounted to PM1 motors?

I have a diagram but I don't understand exactly how they should be wired. Having googled various references, most pictures have them in series but the diagram I have shows them across the coils and I don't understand how or if they should be connected to the common wire.

Sorry if its a dumb question, I have realised that reading electrical diagrams really isn't my forte.

Thanks
 

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QUOTE (eddscott @ 20 Oct 2008, 21:06) <{POST_SNAPBACK}>Does anyone have an actual picture of how diodes are mounted to PM1 motors?

I have a diagram but I don't understand exactly how they should be wired. Having googled various references, most pictures have them in series but the diagram I have shows them across the coils and I don't understand how or if they should be connected to the common wire.

Sorry if its a dumb question, I have realised that reading electrical diagrams really isn't my forte.

Thanks

***To wire them to kill the coils Back EMF pulse they must always be across the coil - the ones you have seen with them in series are probably wired to a diode matrix type control or perhaps to give half wave wiring to allow 2 wires and reversing DC power to power a 3 wire solenoid coil.

If you are talking about either the diagrammes that were part of an earlier thread, or the ones packed with MS, they are correct in both where to put it and which direction to install them!

Richard
 

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Discussion Starter · #3 ·
Ah, so mounted either side of the coils? I was getting confused because I thought they needed to be wired into the common somehow.

Won't be doing any motor wiring for a few days anyway - I realised yesterday I've orderd 29 PM2 motors and not PM1!!

I am officially a half-wit.
 

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Hi
If you mean the diodes as shown in the Gaugemaster / Seep wiring sheet GM Seep wiring sheet for their PCU1 point control unit, then I feel GM are somewhat confusing matters!
They have wired the Seep motors with diodes into the returns (but normally A & B terminals are the feed connections) from the coils and appear to be using negative supply switching for coil power?? Perhaps this is how the PCU1 works, but it isn't a conventional means of operation.
It's more normal to supply negative to all the motors returns (terminal C on Seeps) and then positive to all coils (Terminal A & B on Seeps) via the studs (for Stud & Probe) or passing contact switches/push buttons etc. Often all fed from a CDUs output too
Confused even more now!!!
 

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QUOTE (Flashbang @ 21 Oct 2008, 00:15) <{POST_SNAPBACK}>Hi
If you mean the diodes as shown in the Gaugemaster / Seep wiring sheet GM Seep wiring sheet for their PCU1 point control unit, then I feel GM are somewhat confusing matters!
They have wired the Seep motors with diodes into the returns (but normally A & B terminals are the feed connections) from the coils and appear to be using negative supply switching for coil power?? Perhaps this is how the PCU1 works, but it isn't a conventional means of operation.
It's more normal to supply negative to all the motors returns (terminal C on Seeps) and then positive to all coils (Terminal A & B on Seeps) via the studs (for Stud & Probe) or passing contact switches/push buttons etc. Often all fed from a CDUs output too
Confused even more now!!!


***Yes, he will be I think! However this gives an opportunty to clarify using seep specific terminal letters for the PM1

the question related to using diodes to control the coils back EMF and was not to do with anything other than that. The solenoids are being connected to a totally different product to the Seep PCU1.

The diodes should be mounted as follows:

(1) One diode from Terminal C (C is the common) to terminal A
(2) The second diode from Terminal C to terminal B

Richard
 
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