petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- Semi-retired engineer
I had an interesting conversation with myself this afternoon.
A customer wants us to make a piece of equipment for them that features 820V L-L 3 phase power.
However, all loads are switched L-N, only one load per contactor.
No single contactor will ever see anything but 475V to neutral, single phase.
Q: Can I use standard contactors, fuses, etc.? Or I am doomed to buying very expensive relays to switch the loads.
Part of me is saying that the answer is obvious that I have 800+ volts and need to buy equipment rated for 800+ volts. Another part of me is saying it is a 475V system because no single component will ever see more than 475V to neutral.
If it matters, I do not know if the neutral is really connected to earth or not at this stage.
A customer wants us to make a piece of equipment for them that features 820V L-L 3 phase power.
However, all loads are switched L-N, only one load per contactor.
No single contactor will ever see anything but 475V to neutral, single phase.
Q: Can I use standard contactors, fuses, etc.? Or I am doomed to buying very expensive relays to switch the loads.
Part of me is saying that the answer is obvious that I have 800+ volts and need to buy equipment rated for 800+ volts. Another part of me is saying it is a 475V system because no single component will ever see more than 475V to neutral.
If it matters, I do not know if the neutral is really connected to earth or not at this stage.
