'Open point' on an 11KV ring main?

Question

What is the 'open point'....can it be changed?

where would it be?

Answer 1

As the name implies ring main units (RMU) employs the looped connection, that is, power supply is coming from both ends of the loop wiring. The advantage of this over the radial feed is that should there be power failure in one end, power could still be supplied from the other end.

However, it is not recommended to close all the switches in the RMU'S to form a complete loop or series connection as any fault in the system will affect both ends of the power supply.

Normally, somewhere in the middle of the loop one switch is opened ( open point) to isolate the two supply points.

Can it be changed?

Yes, depending on the actual load distribution on the two supply points.