For a start, running each off of a separate outlet is a really bad idea, you need to set up a proper industrial enclosure with the correct power supply feed with suitable capacity.
The entry to the enclosure would first be the disconnect followed by suitable fusing for each servo amplifier and power device etc.
There is a copy of Industrial enclosure wiring etc, AKA NFPA79 out there in PDF to get some idea, it is NA based, but most will apply to a UK application.