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 Post subject: Phase swapping in 13.8 kV cabinet
PostPosted: Wed May 06, 2020 7:40 am 
Sparks Level

Joined: Tue Apr 03, 2012 1:28 pm
Posts: 64
Location: Louisville KY
Just curios what the group's thoughts are on this one:

An electrician during a utility switchyard construction project (energized yard with a section being replaced) notices that a 13.8 kV indoor cabinet has A and C phases backwards according to the design. After a lengthy discussion, and due to some verifiable operational limitations, a decision is made to lockout and verify the upstream VCB, and not hang grounds.

The electrician enters the cabinet with voltage-rated gloves, arc flash clothing, no sleeves, no hardhat/faceshield, and lifts the shields from the cables, and shorts each phase to ground to "discharge any static charge." He then proceeds to swap the phases with no issues.

What would you say in that scenario if you were informed after the job had been completed?


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 Post subject: Re: Phase swapping in 13.8 kV cabinet
PostPosted: Fri May 08, 2020 6:12 am 
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Joined: Wed May 07, 2008 5:00 pm
Posts: 879
Location: Rutland, VT
The utility I used to work for never would have allowed that. Grounds needed to be hung, visible breaks on both sides and test for de-energized prior to working.

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Barry Donovan, P.E.
www.workplacesafetysolutions.com


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 Post subject: Re: Phase swapping in 13.8 kV cabinet
PostPosted: Sat May 09, 2020 4:18 am 
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Joined: Tue Apr 03, 2012 1:28 pm
Posts: 64
Location: Louisville KY
I received a call after this happened and the utility wanted my opinion. I’m with you - I’ve never seen a utility allow work like this without grounds applied, and usually it’s required to form a local equalized potential zone. The reason the contractor gave was downtime limitations on the upstream transformer that could have a detrimental effects on the grid.

Obviously OSHA allows utility energized work - it happens often, but the requirements greatly increase when doing so.

Just curious what this group thinks about it. Thanks for your reply!


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 Post subject: Re: Phase swapping in 13.8 kV cabinet
PostPosted: Sun May 10, 2020 10:05 am 
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Joined: Wed May 07, 2008 5:00 pm
Posts: 879
Location: Rutland, VT
The utilities I worked for would require that the work be considered energized work if no grounds were applied, even if there are visible breaks and the circuit tested dead. All energized work procedures would have to be followed. Typically this extends the down time.

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Barry Donovan, P.E.
www.workplacesafetysolutions.com


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 Post subject: Re: Phase swapping in 13.8 kV cabinet
PostPosted: Mon Jun 01, 2020 1:27 pm 
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Joined: Sat Nov 21, 2009 10:23 pm
Posts: 124
Location: Ohio
What was the actual concern, metering?


Kenneth Sellars wrote:
Just curios what the group's thoughts are on this one:

An electrician during a utility switchyard construction project (energized yard with a section being replaced) notices that a 13.8 kV indoor cabinet has A and C phases backwards according to the design. After a lengthy discussion, and due to some verifiable operational limitations, a decision is made to lockout and verify the upstream VCB, and not hang grounds.

The electrician enters the cabinet with voltage-rated gloves, arc flash clothing, no sleeves, no hardhat/faceshield, and lifts the shields from the cables, and shorts each phase to ground to "discharge any static charge." He then proceeds to swap the phases with no issues.

What would you say in that scenario if you were informed after the job had been completed?


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