Accessory Diagrams

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

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

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

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