I recently bought a new 3-phase saw for my workshop. Before the saw arrived I had an electrician install some new cable and an isolator, and he left a length of cable from the isolator ready for the saw.
He could not get a suitable wylex triple breaker in time so he used 3 singles (each at 20 amp).
While he was fitting the breakers there was a loud bang, sparks flew and the lights went out. This happened again 10 minutes later but he eventually got it sorted and then he left.
The plan was for him to come back to connect to the saw.
The saw was delivered a couple of days later and the mechanic who was commissioning it wanted to wire it in so that he could run it and check it was cutting square etc. He said the electrician should check out his connections to sign it off.
He told me two things: one was that the cable was in the 'new' colours and the electrician should have put on some kind of a sticker explaining which colour was going where. The second was that he couldn't earth the machine as the electrician had used 4 core cable and had used the metal wires in the sheathing to connect to the earth at the isolator, but the box on the machine is made of plastic so it couldn't be earthed using a gland. It seems it will need an earth wire running alongside the cable to wire into the earth terminal in the machine.
I hope this is all clear, there's more to come.
Once the machine was up and running we both noticed a slight tingling feeling from the aluminium sliding carriage, which stopped when we isolated the machine.
I have several questions for anyone who is interested or feeling helpful.
1. Should the electrician have placed a sticker because of new coloured wiring?
2. Is it ok to use 3 single breakers instead of a triple one (if it trips will they all go or just one or two)?
3. Is it normal to create loud bangs and sparks flying?
4. Should the electrician have used a 5 core cable (is there such a thing?) so that there would have been an earth wire?
5. Why is my machine tingling and will earthing it stop this? If this is the case, then does it mean that there will be a constant loss of voltage to earth?
Questions 2 and 5 are the ones that concern me the most, the electrician is coming back on Tuesday to finish off and I would like to know what is right or wrong before he returns.
Any help will be much appreciated.
Pete
He could not get a suitable wylex triple breaker in time so he used 3 singles (each at 20 amp).
While he was fitting the breakers there was a loud bang, sparks flew and the lights went out. This happened again 10 minutes later but he eventually got it sorted and then he left.
The plan was for him to come back to connect to the saw.
The saw was delivered a couple of days later and the mechanic who was commissioning it wanted to wire it in so that he could run it and check it was cutting square etc. He said the electrician should check out his connections to sign it off.
He told me two things: one was that the cable was in the 'new' colours and the electrician should have put on some kind of a sticker explaining which colour was going where. The second was that he couldn't earth the machine as the electrician had used 4 core cable and had used the metal wires in the sheathing to connect to the earth at the isolator, but the box on the machine is made of plastic so it couldn't be earthed using a gland. It seems it will need an earth wire running alongside the cable to wire into the earth terminal in the machine.
I hope this is all clear, there's more to come.
Once the machine was up and running we both noticed a slight tingling feeling from the aluminium sliding carriage, which stopped when we isolated the machine.
I have several questions for anyone who is interested or feeling helpful.
1. Should the electrician have placed a sticker because of new coloured wiring?
2. Is it ok to use 3 single breakers instead of a triple one (if it trips will they all go or just one or two)?
3. Is it normal to create loud bangs and sparks flying?
4. Should the electrician have used a 5 core cable (is there such a thing?) so that there would have been an earth wire?
5. Why is my machine tingling and will earthing it stop this? If this is the case, then does it mean that there will be a constant loss of voltage to earth?
Questions 2 and 5 are the ones that concern me the most, the electrician is coming back on Tuesday to finish off and I would like to know what is right or wrong before he returns.
Any help will be much appreciated.
Pete