110v at junction box (should be 240v)?

Question

i am working in a petrol station where there is 4 wire armour cables entering a junction box each supplying 4 lighting circuits
3 have 240v supply one has 110v in which the lights are not working they may be through a contactor im not sure yet im trying to resolve this problem could you help me please
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Answer 1

Your question is very unclear, and it seems to me that you don't have much experience of electrics, especially 3 phase supplies. I think you should get someone in that knows what they are doing.

You say you have a four core SWA cable(s) (One or more??), each supplying 4 lighting circuits. Each what? core? if so, where is the neutral? if you mean circuits from switches. If you mean individual lighting circuits then you can only have two on a four core cable, i.e. one feed and one neutral X 2 = 4 cores. Where is the junction box? What cables leave the box? What was the reported fault?

Answer 2

First don't mess with electricity if you don't understand it
GET A QUALIFIED ELECTRICIAN IN it will cost a lot ... but a lot less than a funeral or loss of earning while you are in hospital

I THINK you have a 3 phase supply

( four wires armoured cable =three phase)
Each phase is 110 Volts

TWO phases will make 220 volts

BUT DON'T MESS WITH THREE PHASE SUPPLY

Answer 3

Call someone qualified, before you kill yourself, start a fire, and blow up the petrol station.

Answer 4

petrol station require certified specialist electritions -- if you violate this you will void your insurance agreement.