RBT Circuit Diagram

This is the circuit inside the RBT hand control box.

The diodes have been added to help prevent damage to the controller in the event that the plug is incorrectly orientated in the socket.

In May 2025 the two position forward / reverse switch was changed for a three position forward – off – reverse type. This required the addition of an extra diode as below.

This extra diode means that the battery meter will read slightly lower in reverse than in the forward direction. We use 1N5819 schottky diodes which have a voltage drop of around 0.4V. These are available from RS, part number 486-4460.

Having an off position between forward and reverse does mean that our more advanced controllers [the Pro series] may restart if the transition between forward and reverse is done slowly. This restart can be avoided by operating the switch quickly, or alternatively a capacitor can be connected across white and green, a 100uF 50V electrolytic will allow about 4 seconds before the restart occurs. * This capacitor has been added to all RBTs from serial number 26500 onwards.

The centre off position also means that horn relay 2 will not operate if the rocker switch is in the centre position.