bigger 600A CT's or run in parallel?
Posted: Tue Oct 18, 2016 10:49 am
Hi Everyone,
I am connecting a Omnimeter II v.3 (3phase - 4wire) to a new Cummins diesel genset that puts out 600A per leg. I ordered the EMK 600A solid CT rings (only type offered by EKM for 600A) and these have a 45mm inner diameter. I am running three electrical cables in parallel for each phase (triple lugging 4/0 cable so a total of 9x hots, 3x neutrals and 1x ground) but my 4/0's wire has an outer diameter of 24mm. Pulling out my geometry book says that if the wire's was just a bit skinnier (20.8mm OD) I could fit three inside the 45mm CT, but alas, only one of the 24mm wires will now fit. Similarly, three 24mm wires fit inside a 52mm hole, so that is the minimum size I am looking for.
Is there a 600A 26.6mA CT ring available with a larger inner diameter? Rogowski coils? Or is my only solution to parallel three 600A CT's for each leg? I can't reduce the size of the wires and there is no other place to put the CT's where the diameter is smaller.
I saw paralleling CT's on another chat here on this forum:
http://forum.ekmmetering.com/viewtopic.php?f=8&t=3226
Kind thanks in advance,
Eric
I am connecting a Omnimeter II v.3 (3phase - 4wire) to a new Cummins diesel genset that puts out 600A per leg. I ordered the EMK 600A solid CT rings (only type offered by EKM for 600A) and these have a 45mm inner diameter. I am running three electrical cables in parallel for each phase (triple lugging 4/0 cable so a total of 9x hots, 3x neutrals and 1x ground) but my 4/0's wire has an outer diameter of 24mm. Pulling out my geometry book says that if the wire's was just a bit skinnier (20.8mm OD) I could fit three inside the 45mm CT, but alas, only one of the 24mm wires will now fit. Similarly, three 24mm wires fit inside a 52mm hole, so that is the minimum size I am looking for.
Is there a 600A 26.6mA CT ring available with a larger inner diameter? Rogowski coils? Or is my only solution to parallel three 600A CT's for each leg? I can't reduce the size of the wires and there is no other place to put the CT's where the diameter is smaller.
I saw paralleling CT's on another chat here on this forum:
http://forum.ekmmetering.com/viewtopic.php?f=8&t=3226
Kind thanks in advance,
Eric