Hello,
We have a 208v 3-phase panel in our server room filled with 20amp circuits. We would like to change them to 30amp circuit that goes to the twist lock circuits so we can plug in bigger equipment. If all possible. What I can’t figure out is how many 30-amp circuits we can get in the 208v 3-phase panel.

Willy281

Each dedicated 30 amp 208 volt circuit will use a 2 pole breaker.

What also needs to be done is calculate the total new load of all the circuits to be sure the main feeder for this panel can handle the new total load.

Allow 80% capacity of the feeder rating, if 200 amp allow 160 amps max load, for example.

I have found in real server rooms, the actual load ranges between 50- 70% of nameplate KW rating. Best to use KVA if available. Check your equipment before installing more load if possible. Check afterwards. Try to use PDU strips in racks that have an amp meter in each. APC makes these.

When increasing KW load in a server room, also plan on needing more cooling.

My experience is exclusive electrician for a banking data center, with 1000 KVA genset and double ended redundant 1200 amp service , ranges between Tier 2 & Tier 3 level, among several other smaller server rooms and DR sites.