Combined MV/LV Switchgear Room 3

[Instrument1352]

Hi,

We are considering use of an existing 60+ years plant. The main substation has both MV and LV gear in the same room, opposite each other. All the oil and air breakers, protection relay, etc. are still the original 1960's. There is an opportunity to upgrade if necessary.

Is it a requirement to have separate rooms for LV & MV? I know it is ideal but can think it is not always feasible.

Thanks

 

[Padlock01]

Hi Instrument1352
First I would dump the oil switchgear and Install SF6 MV switchgear depending on voltage level.
issue a Single line diagram (SLD) to would be tenderers for switchgear they will advise on Type
of protection relays.
As far as the separation of MV / LV switchgear I would advise separation.

 

[dpc]

This will dictated by local codes, and you haven't given a location. In the US there is no requirement for separate rooms for HV and LV switchgear.

 

[waross]

One possible issue is "Entry by Authorized Persons Only".
Many training programs limit entry to switch rooms to qualified persons.
Combining the rooms may exclude entry by workers who are qualified only for low voltage systems.
It depends.
I remember an accident in a combined 480 Volt, 4160 Volt switch room.
I was in the switch room when it happened.
Miraculously no-one was injured.
The worker was qualified, for 480 Volt systems (barely) and should never have been near 4160 Volt switch-gear.

Bill
--------------------
Ohm's law
Not just a good idea;
It's the LAW!