Network protectors

We're curious as to how other utilities are treating dead front protectors. Specifically, when a worker is opening a cabinet to a dead front protector, can this be considered as non-exposure to energized equipment?

Rob
robert.gray@avistacorp.com

I would vote 'YES'. With 'live break' or 'dead break' elbows there are no exposed energized parts. Without exposed lived parts, Arc Flash is not required. The low voltage side would be a different story.

Of course, I would treat this the same way as entering a manhole with energized cables. There are live parts, but you need to be in FR PPE and tic trace for voltage to verify there are no cracks or leakage in cables - then you could remove FR.

Rob,

Not sure of the type of cabinet you are referencing. Can you be more specific?

Alan

Network protector access

Alan,

The "cabinet" I was referring to, would probably be better described as the enclosure door. This is to a network protector, such as an Eaton CM52. The conductors are insulated and isolated in a composite resin frame. This is in contrast to the older protectors, where exposed conductors are accessible as soon as the door is opened.

Thanks,
Rob

Approval

Does the cabinet have any approval rating with the door open - with the secondary protection system?

I work for a utility in the south and we wear the FR clothing ANYTIME we open or move the NP switch handle. We wear class 1 FR clothing as of right now. The company will be conducting studies on the secondary 2010 so who knows what calorie we will be wearing. We have GE CMD CM-22 and CM-52 netowrk protectors and we wear class 1. It doesnt matter if its dead front or not. While youre reading this thread do you know anysites that have people talking about network protectors. I have been trying to find some and cant locate anything.

I would consider opening a door to expose dead front parts to not be an interaction likely to cause a fault. Why was the door opened, though? Is there another action that follows?

Of course secondary networks fall under the less than 1000 V 4 cal/cm^2 exception.

the door could be opened for a number of reasons. i.e. maintence, inspections, son on and so forth. There has been accidents even fatalities on just racking in a piece of equipment some due to human error and some due to mechanisms.