2 speed switch wiring - 3 phase motor
Hi there
I am hoping someone may be able to chime in with some advice on wiring up a switch that is on an old BCA Jig borer. The machine has a 3 phase 2 speed motor. The three phase power comes into the machine stand isolation switch and then from there to the two speed switch. On the power input side to the switch there are 4 wires - the three phases and an earth. On the motor side there are 6 wires and happily they are tagged with wire identifier and these match up with the switch terminals so this all seems very straight forward and matches the wiring diagram I have which I have attached a pic of.
https://uploads.tapatalk-cdn.com/202...8978acf998.jpg
Here is the switch
https://uploads.tapatalk-cdn.com/202...e6501bc42b.jpg
https://uploads.tapatalk-cdn.com/202...2125d50363.jpg
My confusion is that there is no obvious terminal to run an earth wire (the 4th wire come in on the power side of the switch). I am not sure where this should go?
Interestingly there is one terminal that has been left wired as shown below - this is the only wire that was left on the switch and all other wires were tagged and it is obvious where they go. B1 green wire connect and then there is the black wire to the only terminal on the switch that doesn’t have a label on it which has made me suspicious of it and if.
https://uploads.tapatalk-cdn.com/202...8155270822.jpg
So can anyone shed any light on where I should be looking to send the earth to?