Gaugemaster GM500 relay with facing points

[spikey]

While lack of funds prevent me from progressing with my facing three-ways/frog switching/point motors issue as per my other thread, I'm now wondering if I can effect an improvement in another area of the layout.

 

I have a pair of facing points (i.e. standard 2-way electrofrog) with Gaugemaster PM2 solenoids which are fired via a single GM500 relay in order that both respond to the same switch movement on the panel.  This means that all six outputs of the GM500 are used.  It would be nice if I could have indication on the panel of which way the relay/points are switched, but it's not obvious to me how I might do that, given that the relay output I'd normally use is already used. 

 

Is there a relatively simple way of achieving my objective? 

[Brian]

How are you operating the GM500?

Its a latching relay and requires a pulse to one relay coil to energise and latch the relay and it then remains mechanically latched until a second pulse is sent to the other relay coil to release the relay!  Its not designed to operate solinoid motor coils such as the Seep PM2

 

 

Edited November 28, 2021 by Brian

[ejstubbs]

38 minutes ago, Brian said:

Its a latching relay and requires a pulse to one relay coil to energise the relay and it then remains mechanically latched until a second pulse is sent to the other relay coil to release the relay!  Its not designed to operate solinoid motor coils such as the Seep PM2

 

Indeed: using a latching relay to switch solenoid point motors will have the same effect as using a standard (i.e. not momentary or passing-contact) SPDT switch - i.e. generally, not a good one.

 

It's perfectly possible to "fire" two point motors from one momentary SPDT switch (assuming your CDU is up to the job) without resorting to relays or any other electrical jiggery-pokery.

 

1 hour ago, spikey said:

It would be nice if I could have indication on the panel of which way the relay/points are switched, but it's not obvious to me how I might do that, given that the relay output I'd normally use is already used. 

 

Is there a relatively simple way of achieving my objective? 

 

Based on what you wrote on this thread, and your rather "spikey" insistence that you had followed the Gaugemaster wiring diagrams for the GM500, I suspect that you're actually using the relay for frog polarity switching, not for driving the PM2 point motors as your OP to this thread suggests (if you are using them for that, then you haven't followed the wiring diagram).  In which case I'd suggest that one solution to your requirement would be to add another GM500, to drive LEDs on the control panel which indicate which way the points are set.  Both the point motors and the two GM500s would be fired from the same momentary SPDT switch on the control panel.  This solution does assume/require that your CDU is up to the job of firing all four solenoids at once.  (Note that the relay controlling the LEDs could - in fact should - be located adjacent to the control panel, you don't have to run wires back to the control panel from the points using this approach.  That's a potential benefit compared to an approach based on microswitches driven by the points - although you could use microswitches for frog polarity switching, as discussed on the thread linked above, and use the relays for driving the LEDs.)

 

Another potential solution could be to use ordinary (i.e. not momentary) SPDT switches - which would show the points settings on the control panel by their position - in combination with push-to-make pushbutton switches to fire the point motors and the frog polarity switching relay.  That would not require additional relays or microswitches, but would mean different switches at the control panel end of things.

 

No doubt others will be able to contribute further alternative solutions.

Edited November 28, 2021 by ejstubbs

[spikey]

Cheers chaps.  I should have made it clear that the facing points are both fired by the CDU via the one centre-off momentary SPDT switch.  The GM500 is used for switching the frogs on both points simultaneously.

 

I note the suggestion of changing to a DPDT switch + pushbuttons, but for me the obvious thing to do is introduce a second GM500 so each point has its own, keep the one momentary switch, and use one of the spare sets of relay contacts to switch the LEDs.