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Don't drop the screwdriver


red750

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Astonishing arc as they leave at the end!

I watched it several times, kept thinking I'd be really nervous that the red ground clamp he had on the cable could be knocked/pulled off during the procedure.

Was the wrap he was putting on to stop the yoke thing from working it's way down the cables? If so, I'd say they are very much in need of some simpler quicker attachment.

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1 hour ago, IBob said:

Astonishing arc as they leave at the end!

I watched it several times, kept thinking I'd be really nervous that the red ground clamp he had on the cable could be knocked/pulled off during the procedure.

Was the wrap he was putting on to stop the yoke thing from working it's way down the cables? If so, I'd say they are very much in need of some simpler quicker attachment.

Hmmm.  Out in the weather. Rainwater as an electrolyte. Out of sight for easy inspection.  Lots of electricity. 


I say a simple same metal spiral clamp would be the best solution over any form of screwed clamp with different metals involved that has the perfect conditions to corrode and fail without warning. 

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On 20/04/2022 at 10:06 AM, kasper said:

Hmmm.  Out in the weather. Rainwater as an electrolyte. Out of sight for easy inspection.  Lots of electricity. 


I say a simple same metal spiral clamp would be the best solution over any form of screwed clamp 

 

The problem very high voltages is the corona discharge.  Any sudden change of shape (eg bolts) will create an additional high voltage that can cause a discharge, between phases in this case.  The mathematics of corona discharge is the same as a stress raiser on a rotating shaft.  

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16 minutes ago, Geoff_H said:

The problem very high voltages is the corona discharge.  Any sudden change of shape (eg bolts) will create an additional high voltage that can cause a discharge, between phases in this case.  The mathematics of corona discharge is the same as a stress raiser on a rotating shaft.  

One of the many reasons I try to play with high voltage as little as possible - I’m very good at following wiring diagrams and processes drafted by people who know what they are doing and what’s safe for me to do. 

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I actually commissioned the Eraring power station end of the first 500kV power line in Australia..  the scary thing is a 330/500kV switchyard on a wet dark night it crakles and sparks.  I worked at Vales Point power station when we had 330kV current transformer explosions.... Very very scary.

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Digressing, but when the first of those CT's exploded in Qld, nobody knew why, but someone reported an increase in RF noise in their AM radio. So, I ended up wandering around HV switchyards nervously aimimg a alloy yagi antenna at CT's, looking for the rising RF that might indicate impending explosion. My apprentice followed me to carry the spectrum analyser. The engineer who thought this was a good idea, stayed in his cosy safe office.

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I was an engineer but we used the same method to discover a faulty CT.  We discovered the RF radiation after an operator said that now that a ct exploded that he could watch tv again...

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  • 4 months later...

I'm retired too...  never worked so hard in my life. Actually I "retired " at 50, and the first thing I did was build a kit-house for my son. It was much harder work than I had got used to.

I remember using a "U " tube for leveling the house while the real builders all around used laser levelers. ( the real builders all used the f word all the time and one day one of them made a mistake which nearly got him thrown off the effing  roof by all the subsequent lots) . It was all great fun.

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  • 1 month later...

Quite right kasper about high voltage. A long time ago, somebody died when the high voltage arced across about a meter or so to get a control-line model flier.

He had been careful to make sure that he wouldn't touch the lines, but the ability of extremely high voltage to jump was something that caught him out.

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