Systems connection

[ampere]

Could I connect a three phase power supply to a single phase system power supply without disruption of service and/or destruction of the panel?
I have a three phase distribution panelboard and system and I have to use, alternatively, the single phase AND the three phase power supply.
It's looking stupid, but is a real problem (from supplier's drawings...!).
Thanks and regards.

 

[dpc]

If I understand your question correctly, you can not do it. The three-phase supply and the single phase supply cannot be connected to the same panelboard.

However, you should be able to supply single-phase loads from the three-phase supply.

I don't understand why you need to use the single phase supply.

dpc

 

[jbartos]

Suggestion: My interpretation of your posting is as follows:
1. There is a system that has to be smoothly transferred from a single phase power supply to the three phase power supply and vice-versa.
2. If 1. is correct, then the next assumption is that the three phase power supply and the single phase power supply have the same voltage, frequency and fuse or circuit breaker protector rating.
3. If 1. and 2. are correct, then a fast static transfer switch may be one solution, if you can tolerate about 4milliseconds disruption in the power supply.
4. If 3. does not do, then you will need an uninterruptible power supply, that you can get either for 3phase supply or single phase supply, depending on circumstances.