Installation and Wiring

Motor Speed and Performance Curves

We’ve had a couple of cases recently that made us think about the importance of getting the gearing of an electric motor correct. Whilst it is true that electric motors can give good torque at Read More

Loco Wiring: Auto Reversing Lights

Some models have separate forward and reverse lights that need to change automatically when reverse is selected. The 4 relay version of the HRB can be configured to do this by following the diagram below. Read More

Improving Heat Dissipation

We’re finding that more of our controllers are now being used in warmer situations, both in hotter countries, and in small enclosures with restricted ventilation. So we thought we’d write this guide on improving heat Read More

A Basic Installation

We often get asked for a full list of the parts needed when installing a controller. Although that’s a bit of a “how long is a piece of string” question, here is our view of Read More

Component Suppliers

We’ve put this page up to list handy sources of the sorts of components often needed for motor installation. Connectors PEI- Genesis    

Motor Noise Suppression

Electric motors are electrically noisy, the sparks commonly seen at the brushes are a source of radio frequency interference [RFI] that can interfere with both the host controller and other systems. Good motor noise suppression Read More

How To Wire Up a Porter 5

We were asked if we could make some videos on how to wire up our controllers. First up is Dillon demonstrating how to wire up a Porter 5 controller. Dillon was our first work experience Read More

Pro-150 with shunt wound motors

Here’s a diagram showing how to use the Pro-150 with shunt wound motors. The principle is to use the brake driver on the Pro-150 to activate a relay that feeds the field winding, and to Read More

Catching diodes

If you have horns or relays fitted to your vehicle, you should fit catching diodes, one across each device to prevent a damaging voltage spike, why? read on for the full story…. Coils, inductance and Read More

Multi speed control

We’ve been asked for a way to switch a motor between a number of pre-set speeds [ multi speed control ]. Here’s a simple little circuit that we put together for the 4QD range but Read More

Double Heading Wiring Diagram [DNO]

This diagram shows how to connect two DNOs in different model locomotives together using the expansion port.     You can download a PDF version here. For the slave cable we recommend using a bulgin Read More

Driving the DNO by Raspberry Pi

Our DNO range is ideally suited for use as an interface between a Raspberry Pi, Arduino  etc, and a motor. The Pi can provide a PWM output via its GPIO pins and this can be Read More

Pro-150 Basic Wiring Diagram

This diagram shows a basic wiring scheme for the Pro-150 running on 24V with ignition and reversing switches. For clarity we haven’t shown the optional display / programmer which connects via 2 cables to its Read More

Switching for Double Heading

We were asked for a diagram for a double heading switch that could let either loco be at the front of the pair, and could be facing either way. This seems to make selection of Read More

Fuses and Circuit Breakers

Choosing fuses and circuit breakers is a difficult subject…… Difficult because motor currents in most applications are very peaky. Difficult because the controller’s battery current is not the same as the motor current. Difficult because Read More

Radio Control Wiring Hints

Any radio controlled machine with motors has potential problems, and this page of radio control wiring hints hopefully helps to identify and solve them. The block diagram shows the electrical system of a typical radio Read More

Wiring for Push Button Use

This diagram shows how to connect a Pro or DNO (or earlier NTX and NCC) series controller for push button use, or with a centre-off switch. Note that the diode shown between the buttons must Read More

Loco Wiring: Hand Control & Horn Relay Board

4QD’s Reversing Bell throttle hand control and associated Horn Relay Board are designed to simplify miniature Loco wiring whilst maximising features available. The Reversing Bell throttle gives a dead man speed control and may be Read More

UNI / Egret Wiring Options

The Uni and Egret both have a 4 pin input connector, but only require 3 wires for input. This is done to allow different options to be selected by varying the input wiring. Standard 10K Read More

Good Wiring Practise

Our controllers get used in a wide variety of applications often switching large currents (several hundred amps perhaps) at around 20kHz. This makes the wiring used with them more critical, and this page tries to Read More

Multiple Controllers [Double Heading]

This page describes wiring that allows multiple Pro-150s and 4QD series controllers to be controlled from a single speed potentiometer. This is useful when double heading model locomotives. As the Pro-150 is a programmable controller, Read More

Double Heading Switch

We were asked for a system such that either loco could be at front and could be facing either way. This seems to make selection of reverse very complicated, but it is in fact quite Read More

Foot Pedal

4QD’s Bell throttle assembly is a finger-tip operated ‘position sensor’ which is also very suitable for use as a position sensor for a foot pedal operated throttle. The diagram shows how it might be done. Read More