A variable speed drive module

A variable speed drive module comprising a power supply input 3 (fig 1) to be connected to a source of power. The module comprises a switching arrangement 4 which is controllable to modulate power input via the power supply input and to output variable frequency drive signals to a motor output 5 (fig 1). The module comprises a first control connector 7 (fig 1) which is coupled to the switching arrangement 4 and is configured to connect removably to a second control connector 8 provided on a control arrangement 9, to receive control signals from the control arrangement. The switching arrangement 4 is incapable of outputting variable frequency drive signals to the motor output 5 if the control connectors are disconnected from one another, thus disabling the device. The variable speed drive module may further comprise a control arrangement comprising a second control connector and an attachment arrangement to allow it to releasably attached. The control module may comprise a processor, a communications module communicating signals between the processor and the second control connector and a memory for storing instructions to be executed by the processor.