4QD controllers are used for locomotive speed control by model engineers worldwide, both private and commercial. Indeed our DNO controller, and its predecessor the VTX, were designed specifically for this application. Our model locomotive customers tell us that our controllers give really smooth operation and are simple to install. Many have controllers still going strong after 20+ years. All our controllers have adjustable acceleration and deceleration ramp times which can be adjusted to give realistic locomotive speed control.
The size of controller you need depends on the power and current rating of your motor. As a general guide the following ranges are suitable for model locos:
DNO range – for small/mid size locos up to 5″ / 7¼ ” gauge – with motors up to 100 amps.
Pro-150 – for mid size locos up to 7¼ ” / 7¾ ” gauge. This has a number of settings which can be changed via the optional display / programmer, but will still work out of the box with the standard settings [just like the older Pro-120].
Pro-160 – for mid size locos up to 7¼ ” / 7¾ ” gauge. With a 2 line display that can be mounted remotely the Pro-160 has features designed specifically for locos, these include a dead mans handle input, a slow / fast mode switch to allow new driver training, built in radio control input, and readouts of voltage, current, and temperature. The Pro-160 also does away with relays for long term reliability
4QD range – for large locos with motors up to 300 amps.
We have a list of all the locomotive sites and suppliers that we know about, please let us know if you’d like to be added to the list.
There are also some locomotive knowledgebase articles that address loco specific issues.
Here are just a few of the fantastic models that our customers have built.
From time to time we get asked if we can do special projects. Here’s a picture of a custom control box that we built.