Current Transformer leads/other wires in same conduit
Current Transformer leads/other wires in same conduit
(OP)
I have two conduits to an outdoor switchgear. One conduit will contain 24 VDC power and control wiring. The other will contain 120 VAC power wiring. Also, in the switchgear there is a set of 100:5 Current transformers. I need to bring the leads from those ct's back in one of the two conduits. Which one?






RE: Current Transformer leads/other wires in same conduit
RE: Current Transformer leads/other wires in same conduit
RE: Current Transformer leads/other wires in same conduit
I understand the constrictions of using existing conduits, but given the implications of an open circuit on a CT secondary, I would investigate whether it is possible to run another conduit dedicated to CT and PT wiring.
If not possible, I would go with the 120 volt circuits. I would try to physically arrange the CT wires or cable so that it is unlikely that it would be inadvertently opened under load. Remember that depending on the impedence of the load, a CT secondary may show a very low, supposedly safe voltage under load, but if the circuit is accidentally opened, the voltage will tend to increase so as to maintain the current. The voltage can go extremely high until it is limited by saturation of the CT.
My first choice as I said would be with the other AC wiring, all other things being equal. However, I it became apperent that by running with the AC circuits the connections may be somewhat confusing, and by running with the DC circuits the CT wiring could be arranged so as to remove all confusion that may result in a disconnect under load, I would go with the DC wiring.
I would consider any scheme that significantly reduced the possibility of confusion in the future to be the preferred method of connection.
respectfully
RE: Current Transformer leads/other wires in same conduit
RE: Current Transformer leads/other wires in same conduit
RE: Current Transformer leads/other wires in same conduit