# 480 vs 4inch rigid



## 360max (Jun 10, 2011)

...too much pressure on the bushing?


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## HARRY304E (Sep 15, 2010)

There was no bushing....:no::laughing:


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## 480sparky (Sep 20, 2007)

HARRY304E said:


> There was no bushing....:no::laughing:


Looks like a grounding bushing to me.


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## HARRY304E (Sep 15, 2010)

480sparky said:


> Looks like a grounding bushing to me.


Well,,,,



I need better glasses...:whistling2::laughing:


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## 360max (Jun 10, 2011)

looks like the short burnt through the top edge of grounding bushing until it reached the conduit


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## 360max (Jun 10, 2011)

HARRY304E said:


> Well,,,,
> 
> 
> 
> I need better glasses...:whistling2::laughing:


thats ok Harry, the post still counts :whistling2:


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## 480sparky (Sep 20, 2007)

HARRY304E said:


> Well,,,,
> 
> 
> 
> I need better glasses...:whistling2::laughing:


Maybe the plastic burned away.... or got knocked off/broken during installation and was never there.


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## HARRY304E (Sep 15, 2010)

360max said:


> thats ok Harry, the post still counts :whistling2:


Yeah!!:laughing:


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## HawkShock (Nov 27, 2012)

It would be more impressive if it was 277:whistling2:


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## Jlarson (Jun 28, 2009)

It always wins.


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## sparky970 (Mar 19, 2008)

I would blame that on a poor install


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## five.five-six (Apr 9, 2013)

HawkShock said:


> It would be more impressive if it was 277:whistling2:


It was.


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## Ozzy1990 (Jan 24, 2013)

Plastic is still on the bushing


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## yamatitan (Sep 4, 2010)

At least they used bushing these guys didnt but it was only on the 208 side of the transformer. The new tenant didnt need the transformer for what they where doing so I just disconnected it and let the owner decide what he wanted to do.


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## BBQ (Nov 16, 2010)

An old thread of mine. http://www.electrical-contractor.ne...p/topics/119389/4_RMC_vs_Utility_Current.html


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## RIVETER (Sep 26, 2009)

Ozzy1990 said:


> 480 wins
> 
> View attachment 32209


I have to say that it looks as though 480 volts was not involved...Not enough damage.


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## Big John (May 23, 2010)

yamatitan said:


>


That's an interesting one. I see an EGC, so I assume the fault occurred inside the flex itself, and the connections were high enough impedance that the breaker took forever to clear it?


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## HawkShock (Nov 27, 2012)

five.five-six said:


> It was.


Prove it. I don't believe it at all. There is no evidence to prove anything has happened there at all. 
I also don't believe in sarcasm.


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## yamatitan (Sep 4, 2010)

Big John said:


> That's an interesting one. I see an EGC, so I assume the fault occurred inside the flex itself, and the connections were high enough impedance that the breaker took forever to clear it?


Fault happened at the other connector inside the panel that I didnt take a picture of. No bushing on that side either, insulation rubbed through and it was over. Happened at night when no one was in the warehouse not sure how long it took the breaker to clear but it did trip. Not till everything melted though.


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## LJSMITH1 (May 4, 2009)

Ozzy1990 said:


> 480 wins
> 
> View attachment 32209


Ahh...Compression Set (aka cold-flow) of the conductor insulation...will do it almost every time...which is one reason why bushings are required with conductors over 4AWG.

We had a 4" Mogul come in which had 3- 600MCM's in it which were pulled WAAYYYY too tight. 5 days later - BOOM. 1" diameter hole right through one of the hubs.


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