Big change in current draw on either side of a capacitor bank
Big change in current draw on either side of a capacitor bank
(OP)
I am in the business of selling high voltage test equipment and am trying to help out a customer. The customer is a small municipal utility. They have two places where there are capacitor banks installed on a 4160v feeder. In both places they are getting widely varying readings on either side of the capacitor bank. I went out and verified this with two different meters.
Here are the readings from one feeder.
Phase A Upstream 42.2A +.04PF Downstream 5.2A +.71PF
Phase B Upstream 41.9A +.35PF Downstream 15.4A +.85PF
Phase C Upstream 39.7A -.37PF Downstream 15.9A +.85PF
Any clues what would cause this? Any idea how to confirm it and fix it?
Thanks in advance for anyone who can help.
Here are the readings from one feeder.
Phase A Upstream 42.2A +.04PF Downstream 5.2A +.71PF
Phase B Upstream 41.9A +.35PF Downstream 15.4A +.85PF
Phase C Upstream 39.7A -.37PF Downstream 15.9A +.85PF
Any clues what would cause this? Any idea how to confirm it and fix it?
Thanks in advance for anyone who can help.






RE: Big change in current draw on either side of a capacitor bank
Is there a detailed 3-line cap bank configuration diagram you can post ?
The two banks are of different sizes judging by the phase currents.
Upstream phase C may have a cap or two with a blown fuse, thus drawing less current. Same reasoning for downstream phase A but in a big way, perhaps 2 of 3 groups per phase of the cap bank are not energized.
I am guessing that individual caps are not tested, just current load readings taken.
RE: Big change in current draw on either side of a capacitor bank
RE: Big change in current draw on either side of a capacitor bank
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Big change in current draw on either side of a capacitor bank
RE: Big change in current draw on either side of a capacitor bank
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Big change in current draw on either side of a capacitor bank
What is the bank size?
What do you mean upstream and downsteam?
Does the downstream mean the load side of the tapping connection point of the cap bank?
Or, it means the second cap bank at downstream of the first bank?
RE: Big change in current draw on either side of a capacitor bank
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Big change in current draw on either side of a capacitor bank
The general consensus seems to be that the capacitors are oversized and that makes sense with the available data. I am going back to see them late this week or early next week and I will see if they can take the cap bank out of service and read the current again.
RE: Big change in current draw on either side of a capacitor bank