I've worked on the outskirts of a major city in Australia and have found at times the line currents of three phase motors installed across a wide area in the same region run out of balance, but only slightly, maybe one to two percent.
When run on a local generator they always come back into...
Gents,
good morning/evening. We are in the process of specifying CTs for a 22 kV 50 Hz switchboard protection system (Incomers, feeders and bus-zones) and are trying to validate the calcs for CT ratios, burdens etc.
We were using the ABB publication:
Calculation of the Current Transformer...
Gents,
In a project with which I'm involved it is proposed that a squirrel-cage induction motor (1250 HP 3.3 kV) be direct-connected to its dedicated feeder transformer secondary (approx 2,500 kVA) and then started and stopped (running for a week at a time aproximately) by means of the 33 kV...
We are debating fixed vs removable for our next switchgear, 22 kV 1250 Amp about 20 panels two incomers, bus tie in the middle. Prot will be three layer (X,Y and backup)but probably not relevant. I'd really appreciate observations from anyone who has been through the same exercise. Anyone who...
I'm in Melbourne, OZ, ie 50Hz. Can anyone point me to orthodox guidance on FUSE sizing for motors with PF correction capacitors connected in parallel. I will soon have a 25 kW 0.56 PF 415 volt 16-pole motor. I want to bring the 77 amp motor FLC back to a line current of only about 50 amps...
