Relay Wiring Question

[Teeg]

I am using a KW transformer on O-gauge tubular track.  There is an insulated section of track to which several accessories, including a crossing signal, crossing gate and gateman are connected.  When the locomotive crosses into the insulated section of track, it slows down and sparking occurs along the insulated rail.  All of the accessories in this section are connected to the #2 clip within the insulated rail section (nothing is connected to clip 1).  It was suggested to me that a relay might be used in this section to get rid of the sparking and operate the accessories.  I purchased an Azatrax MRAPR-12v DPDT Relay 8A but am confused about how to wire it.  I'm not sure what to hook to the slots on the relay, K1, K2, 2C, 1C, what goes to the NC and NO slots, and how all of this then connects to the KW transformer (i.e., which posts).  Any assistance would be appreciated.

[BigAl 956]

What you are experiencing, sparking and slowdowns are normal if you are using track power for the circuit. The wheels of the train become a switch to provide ground to these accessories. If you powered the accessories with a seperate transformer output instead of using the track then you would not have a slowdown.

Using a relay is a good idea to isolate things. Relays do not draw much power. These accessories all work by having power and ground applied. For the record, when using a KW, ground is the U connection which is fed to the outside rail of the layout.

A relay allows you to use the C-D, 14v connections on the KW to power the accessories without taking away track power.  Since the normal condition of these itemems is off use the normally open side of the relay as the activation. Connect the common side of the acessories to C. Connect the activation side of the accessories to the NO side of the relay and the common side of the relay to D. 

When all this is connected the insulated track will trip the relay and the relay will activate the accessories.

Maybe another member of this forum has a diagram that shows this better. Hopefully this all makes sence.

[ADCX Rob]

BigAl 956

A relay allows you to use the C-D, 14v connections on the KW to power the accessories without taking away track power.

Any drain on the C-D connection will absolutely still drain power from the train, the 145 watt output of the KW is shared amoung all loads, all binding post combinations.  Your suggestion to use a separate transformer is the best solution.

[BigAl 956]

ADCX Rob

Any drain on the C-D connection will absolutely still drain power from the train

The KW will have more than sufficient wattage to handle a train and a couple accessories on seperate circuits. It's made for that.

[ADCX Rob]

[Teeg]

Thanks to everyone for the replies to my question.  I especially appreciate the diagram, which I will follow in connecting the relay today.  I have never wired a relay before, so am grateful for the guidance.  It will be nice to be able to operate the accessories without the sparks and slowdown.

[Teeg]

I replied to this yesterday but it didn't go through for some reason.  Just want to thank you both for the input and the diagram.  I'm going to give this a try today.  Merry Christmas and Happy Holidays to all!