Lever Switches

[Alan564017]

I'm having a problem with getting point motors to work. I have surface mounted point motors connected to lever switches R044 (all hornby), all powered from DC off a bog standard hornby transformer. Plug it in, all work fine, once, then all dead, not even a buzz. I have to unplug it for a while before trying again and getting one go again before they die. All the wiring is good and properly connected, nothing touching, the transformer is fine as I connected it to the track and ran a loco. Its a temporary layout and everything worked fine before. Any ideas?

[Noel]

From memory solenoid point motors usually work off 15v AC using passing contact lever switches rather than 12v DC. If you are using a Hornby 12v DC controller then its circuit protection is probably being triggered when the normal temporary short is created by the lever switch, especially if operated slowly (i.e. period of short is longer than few milliseconds). Many old DC controllers had 12v DC outputs for train track, and separate 15v AC outputs for things like solenoid point motors. I guess if you wait a min or two it will reset and work again once, or work once after ever power off.

 

Solution is to use a different transformer with 15v AC output that has less sensitive short circuit protection, or use a CDU (Capacitor discharge unit).

[Alan564017]

Thanks for the info Noel, the hornby controller is the R965, it says on the top the output is 16V. As I said in the first post, this is a temporary layout, which is dismantled and reassembled 3 or 4 times a year. Prior to this every thing worked fine with all the same constitutent parts