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ekstra   ara
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PostPosted: Mon May 04, 2009 9:20 am 
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Location: Chattanooga TN
On the subject of suits rated beyond 40 cal/cm2, be aware that the arc blast hazard is the real problem which creates the "No PPE can protect you" situation. Molten shrapnel propelled at > 700 MPH, sound exceeding 160 dB, and pressures high enough to collapse lungs or throw a worker 25 feet (a documented event) are some of the hazards. See 2009 70E Annex K, para K.4 and "Arc Blast Pressure" section of this article: [url="http://ecmweb.com/mag/electric_putting_arcflash_calculations/"]Putting Arc-Flash Calculations into Perspective[/url]

As for door-mounted monitors which can allow non-contact testing without opening doors, including addressing the issue of "What if the monitor LEDs are already off?", see [url="http://www.graceport.com/prod_checkvolt.cfm"]GracePort R-1A0033W-NPLPH[/url] (page 2 of datasheet). This is the best solution I've seen.

Has anybody discovered any other solution to this problem, beyond what was posted here in 2007?


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PostPosted: Thu May 14, 2009 10:31 pm 
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Could you not put remote test blocks, granted now you are relying on the wiring to and form the test block to not have any breaks, though this would also add aditional expense.


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PostPosted: Mon May 18, 2009 7:25 am 
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Joined: Fri Nov 09, 2007 3:27 pm
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Location: Texas
SirSpark wrote:
Could you not put remote test blocks, granted now you are relying on the wiring to and form the test block to not have any breaks, though this would also add aditional expense.


If you read the rest of the postings on this thread, you will find discussion on this.

IMO - still - the best solution is permamently installed LED indicators in each phase. The voltage presence is visualy verified before the disconnect is open. It's absence is indicated by the LED turning off when the disconnect is operated. In case of fuses it also indicates blown fuses and a good indicator of welded contacts or missing contact closure.

One important thing to remember, whenever a fault is suspected, one should double verify it's validity to eliminate the failure of the detection, eg. failed indicator.


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PostPosted: Mon May 18, 2009 7:48 am 
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I read half the postings and I would say remote test blocks with LEDs. But in all seriousness this may be a bit overkill depending on where this equipment is installed and what it is supporting.

To avoid suiting up maybe once or twice a year this would obviously not be a very cost effective method.


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