Hi, I have just started out in DCC and have purchased Lenz: TR100 and a Compact, also a LE0512A which I have fitted to a Minitrix 4472 N-Gauge. The engine ran fine on DC, and through channel 0 on the Compact before conversion. The engine is picked up fine on the programming track and I have set the engine to 01 (which reads back fine). When I place the engine on the main track (just a straight length), the engine grumbles, and then runs backwards at full speed, regardless of the dial. Pickups are through the tender, and I am positive I've wired it correctly (right rail = red, left rail = black. Orange to where the right rail used to go, grey to where the left rail used to go). I've insulated the motor from the chassis, and am now stuck. Suggestions greatly appreciated. Many thanks.

-- Dan Johnson (dan_a.johnson@ntlworld.com), September 19, 2004

Answers

Dan,

It sounds like your motor is not isolated from both the right or left wheel pick-ups. Or your motor may be still attached to your headlight and you are getting power to your motor through the blue wire.

You say that your orange and gray wires are going where the power pickups used to go. That doesn't mean the same thing necessarily as going directly to the motor. Directly to the motor and only the motor is what you are after. Verify that your motor is isolated from everything using an ohm meter.

-- Allan Gartner (wire4dcc_admin@comcast.net), September 22, 2004.

Dan,

One more thing. If I am right and your motor isn't really isolated from the power pick-ups, it is possible that you have blown your decoder.

-- Allan Gartner (wire4dcc_admin@comcast.net), September 23, 2004.

Hi, You were absolutely right - on both counts. The brushes are held in place by a spring, and only the bottom one was isolated - so I was getting 12V straight through to the decoder. It's quite poorly now. Once I'd installed my new one (getting expensive now, this hobby!), I had another intermittent problem: there was a spring underneath the motor which was also connected to the bottom brush. This connected with the chassis (only when everything was screwed together) and also caused a short. Fortunately I spotted it and fixed it before I fried another chip. Now I'm up and running, and very, very pleased with myself. Roll on the conversion of my LNER Mallard! Thanks for your help so far. Dan...

-- Dan Johnson (dan_a.johnson@ntlworld.com), September 26, 2004.