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terminal block and breaker screws considered live parts

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jjsparky

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Location
Westminster, Colorado, USA
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Superintendent I/E
1: If I'm in a jbox with tewrminal blocks and the voltage is 208v between screws, are the screws considered exposed live parts?
2: If I'm in a bucket in a MCC that has a circuit breaker in it and the line side is insulated, are the load side screws of the breaker considered exposed live parts?
 
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jim dungar

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Location
Wisconsin
Occupation
PE (Retired) - Power Systems
Anything that is energized (above 24V per NFPA70E) and can be touched by (1/4" is a common maximum hole size for 'finger safe') is consider an exposed live part. If you are using conductive probe type devices, like a screwdriver or the stripped end of a conductor, just about any visible conductive surface may be of concern.
 
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jjsparky

Member
Location
Westminster, Colorado, USA
Occupation
Superintendent I/E
I took a Nfpa 70e class 10 to 12 years ago. I asked the instructor the same questions. He said the screws were “exposed” live parts because to touch them, you would have to purposefully try to make contacts.
 
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