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138Kv Metering PT for Bare Hand

138Kv Metering PT for Bare Hand

138Kv Metering PT for Bare Hand

(OP)
Hello All,
I am a contractor wanting to get bare hand certification on 138Kv line. We have several utility companies that we currently work for that could utilize our bare hand services but they do not want to take on the liability of having an outside individual certify our guys on their facilities. My question is, if we constructed our own field could we take a 138Kv Metering PT and feed 120v backwards to produce the 138Kv voltage? I believe in theory it would work but I'm not sure if the windings would eventually take a dump. We would only need single phase and could make the 3 phases all the same potential with no current. Like I said, it would be to bare hand live line certify our guys. I know we could have a step up constructed or rent a mobile but I'm looking for the cheapest solution in creating the 138Kv/80kv live line. Let me know what yall think.

RE: 138Kv Metering PT for Bare Hand

Egads. There's a good reason some states outlaw that type of work.

RE: 138Kv Metering PT for Bare Hand

A CVT certainly would not work. I have no idea about inductive PTs.

Living in a state that doesn't allow bare hand work, I don't know exactly what you have to certify. Note though, that having all three phases at the same potential would drastically decrease the amount of discharge experienced when personnel attempt to bond either to the conductor or to ground.

RE: 138Kv Metering PT for Bare Hand

There is a possibility to use a single phase inductive Station Service Voltage Transformer (SSVT) rated for 138 kV, 20 to 100kVA capacity that might be considered for the application described. Also check similar application used in high voltage laboratory for testing purpose that could be used as reference.

Since this is unusual application, it is recommended to work with a qualified EE and get the manufacturer involve. Some issues to address are:
• Safety issues and compliance with code and standard.
• Transient voltages and surges. Determine need for surge arrester.
• Primary and secondary protection.
• Voltage regulation at the 138 kV considering small variation at the LV primary side
• Neutral and ground connection both primary and secondary (common neutral?)
See below technical information of the SSVT. Good luck

http://www02.abb.com/global/brabb/brabb155.nsf/bf1...

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