Author Topic: Wiring, DC and the Railpro power module  (Read 1285 times)

carrson

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Wiring, DC and the Railpro power module
« on: September 04, 2017, 10:06:03 AM »
At this time I only have 1 RP unit to run vs my old DC locos that I still wish to run until I can fade them out. I plan to have it set up to switch back and forth between RP and DC. When using DC power my RP will be unplugged and thus the power off. The questions I have are... with the RP power unit off but still connected to the track am I feeding DC power back into the RP power unit ? If so can it be detrimental to the unit?

Thanks
Larry

MtRR75

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Re: Wiring, DC and the Railpro power module
« Reply #1 on: September 04, 2017, 12:26:47 PM »
I am in exactly the same transition situation that you are.  I hooked up a TPDT-center off (triple pole, double throw) switch.  If you have only one DC transformer, you only need a DPDT switch.  Feed both lines of both power supplies to the DPDT switch input terminals.  Connect the output terminals on the switch to your layout.  Use the switch to select which kind of power you want delivered to the track.  When I turn my whole layout on, both power supplies come on, but only one can send power to the track at any time.

To answer your question, with this system, there is never any DC feedback to the RailPro power supply, because BOTH wires exiting the RailPro power supply are turned off when the DC power supply is turned on.   If I plan to run DC only for an extended time, I unplug the RailPro power supply to save wear and tear on it, but this is not necessary to protect it.  If I plan to run only RailPro for an extended time, I simply turn off the DC transformers (using their on-off switches).  But again, this is not necessary to protect the power supplies.

My DC layout has two cabs (transformers).  I hooked up the RailPro to be toggled with Cab A.  I ran the + wire from DC Cab B to the third pole on the triple pole switch -- wired so that Cab A and Cab B are both turned on and off at a the same time.  This assures that both DC cabs are off when RailPro is on.

If you have DC block control switches (as I do) set all of them to Cab A when you want to use RailPro.  If you have a DC directional switch, ignore it when using RailPro.  Use the RailPro Forward/Reverse buttons on the hand-held controller.

The other potential problem is accidentally leaving DC locos on the track when running RailPro (or vice-versa).  You need to be careful not to do that.  If you leave DC locos on a Railpro track, they will immediately take off at top speed as soon as the power is turned on.  No electronic damage, but likely crash damage.  If you leave RailPro locos on DC track, they will just sit there and do nothing.  But this is NOT recommended by the manufacturer.

P.S.  I reread your post.  It sounds like you are planning to put your switch between the wall plug and the power supplies.  Don't do it that way.  Put your switch between the OUTPUT terminals of your power supplies and your track.  That will completely isolate the unused power supply from the used one.
« Last Edit: September 04, 2017, 03:51:38 PM by MtRR75 »

carrson

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Re: Wiring, DC and the Railpro power module
« Reply #2 on: September 04, 2017, 04:36:25 PM »
Thanks for your reply... I was considering install of a double pole switch as you suggested in your last paragraph...makes sense I will do it that way...I am going to set it up so that only one power supply will be on at a time and with the extra double pole install it should act as a fail safe.

Larry

Blueleader

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Re: Wiring, DC and the Railpro power module
« Reply #3 on: September 09, 2017, 10:32:54 AM »
Same situation here, just got RP. Any recommendations on a heavy good quality switch that has plenty of room between connectors?