Arc Resistant

[satnam123]

Hi
We are asked to give a third party opinion as a consulting engineerg in terms of buying a Arc resistant or Arc arrestor 5KV switchgear.
I beleive Arc Arrestor is not the right world, It should be Arc illuminator, I think it is a technology patented by ABB.

I am a small fish so don't have much exp. with switchgear.
What I know is that Europe is way far in power tech than North America and they have been using this ABB tech., which uses a fiber optic cable to trip a upstream breaker when a fault occurs and these breakers are not regular 5 cycle breakers. They are special less than half cycle breakers.
Now how to decide which one any body should buy,
both Arc resistant(type A B or C) + Arc illuminator
or only Arc resistant or only Arc illuminator.

This is all I know and I might be wrong. I would appreciate comments, who have exposure to this area.
Regards,

 

[stevenal]

Arc flash calculations and PPE requirements so far do not recognize arc flash diversion. Current and time are the input quantities for determining incident energy. Since the ABB technology works on the time factor, this can actually reduce the PPE requirements. No flash photography please.

 

[satnam123]

Could you kindly advise me , what does arc flash diversion means and what is your suggestion as an engineer as to what one should opt for?

 

[stevenal]

I was refering to designs that work by directing the arc flash incident energy away from the worker likely to be exposed. So far the calculations deal with open air arcs, or the arc from an open cabinet that directs the energy toward the worker.

 

[davidbeach]

The arc resistant gear is designed to divert the blast from an arc fault out the top, some times also ducted out of the building. This requires that the doors be closed and properly secured. If the door is open while someone is working on the gear, the arc resistant gear provides no more protection than standard gear. Some arc resistant gear lets you access the control wiring while maintaining the arc blast deflecting characteristics for any arc faults on the power circuit. For indoor gear, arc resistant gear may be very expensive over insurance as there are few causes of arcing faults in closed gear in a clean environment with no vermin. For outdoor gear where dust and condensation may be more of a problem, and anywhere that vermin might try entering the gear, arcing faults may occur at anytime, even with the doors closed.

The ABB technology described senses an arcing fault and turns off the power, works just as well with the door open as with it closed, just don't take flash photos around an active system.

 

[RonShap]

I've seen a product that attempts to detect an arc flash, and imposes a bolted fault (crow bar device) to help the upstream device clear faster.

 

[Zogzog]

RonShap, do you have a link for that product?

 

[RonShap]

Arc Terminator by Square D

http://www.squared.com/us/services_...5707400549FB4/$file/040705Terminator_main.htm