Turntable Wiring

Model Railroader General Discussion (Model Railroader)
1

I have a HO layout and I am adding a turntable. I’m having trouble wiring the turntable and have not found any details on the procedure.

What is the best resource or can someone walk me through the process?

Alan

2

Alan:
which part of the wiring is the problem? Can I assume that it’s powering the tracks on the turntable?
What sort of turntable? Is it Atlas, a plastic kit, a wood kit, or scatchbuilt?
–David

3

Or is it indexing that’s causing you problems? There’s a few good solutions to that for both the electrically and non electrically challenged.

4

Alan…you don’t say, but I’ll guess: You want to wire the turntable’s bridge track so that the polarity stays ‘right’ no matter which end of the bridge (zero or 189 degrees) is at the track you’r travelling to. The way most TT’s do this is to have the ring rail in the pit cut into 2 half-circles, insulated from each other. The turntable’s bridge has a pickup under each end, to ride on the ring rail.(like a track wiper) Wire from each wiper to ONE rail on the bridge track. The GAP in the ring rail shoudl be placed at about 90 degrees to where the ends of the bridge are for most operation - you don’t want it right under where the end of the bridge will be when you’re lined up with a track.

5

OOPS!! Hit the’enter key too soon…anyway, when you hook the pit wiring up, you might have to swap polarity on it one time to get the bridge to match your main line track coming in. Get THIS set up right. When you add tracks around the pit, set THEIR polarity by matching the direction on the turntable…(I.e…Set turntable bridge once to match main line coming in, then set other tracks from bridge. When the bridge is spun end -for-end, the ring rail setup will automatically swap polarity on the bridge for you. (If you’re DCC, just wire an autoreverser between the main power and the bridge rails.) Hope that helps! -joe

6

David;
I have the Heljan 804 turntable. It’s a plastic kit that comes with the wipers and brass rings to power the turntable track. I also have an Atlas “TWIN #210” that I purchased when I bought the turntable.

I have power to the track and can rotate the turntable. I have tried using the TWIN and followed the directions from the TWIN but didn’t have any luck making it work so the polarity can be changed and the engine be turned 180 degrees.

I have used a light tester to test power to the TWIN and out on both sides to the mainline and to the reverse loop (directional control) / turntable. I only get power to the mainline side and none to the turntable/reverse loop side? Is the switch bad or is this normal?

Thanks for you help and I look forward to your reply.
Alan

7

Hi Alan:
Sounds as if your Twin may not be working. I’m not really familiar with them, but if you don’t get a light on the TT side, it sounds bad. Try switching the wires so the TT is hooked up to mainline terminals. If your TT works but not the mainline, then the Twin may be bad. Does it have a reverse switch built in? Does that affect anything?
–David

8

David,

Thanks for your help I took it all apart and started over and was able to get it working.

Thanks again,
Alan