NEC 2020 article 230.71(B)(3) and Switchboards

wwhitney said:
All of those disconnects are not in compliance with the 2020 NEC 230.62, in particular 230.62(C), which is what I paraphrased in my previous quote. Most likely those manufacturers have modified their designs, or come out with supplementary guards that can be installed to comply with 230.62(C).

Edit: for a somewhat dated document from one manufacturer on this topic, see:


Cheers, Wayne
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Just look at this video below. They put barriers and say it's compliant with 230.62(c) but it still has exposed line side terminal where the fuses is supposed to be installed...

 
Tainted said:
Look just below the barrier, there’s metal there to hold the fuses on the line side. It’s exposed.
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I admit I have never examined a fused switch like this in person, but when the switch is in the "off" position, aren't those terminals deenergized? As long as the barriers cover the line side lugs and the movable blades of the switching mechanism in the "off" position, you can change the fuse without being exposed to energized conductive surfaces.
 
Tainted said:
Maybe but I thought the whole point was to be able to service the equipment while it is energized.
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Service as in change the fuses or change the load side conductors while the line side conductors are energized, without being exposed to energized parts. Which it appears you can.

Obviously if you try to change the line conductors while they are energized, you are going to be exposed to energized parts.

Cheers, Wayne
 
Tainted said:
Look just below the barrier, there’s metal there to hold the fuses on the line side. It’s exposed. I circled in redView attachment 2575393
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What Wayne said. The fuse holders are on the load side of the switch component. So you can turn off the switch and replace the fuses without them being energized. And the extra barriers are supposed to keep you from contacting the still energized terminals on the line side of the switch component if you're a klutz or someone bumps into you.

Likewise, for panelboard type service equipment, any bussing or terminals on line side of the main breaker will now be covered or guarded. MLO panelboard service equipment is no longer allowed.
 
I also work in the NYC area (PE with both design and contracting experience). Currently we do alot in the power system study world and my colleagues at the local 3 shops are all baffled how they are going to meet this code section. If I am not mistaken there have already been requests for clarification to the code committee.
 
jaggedben said:
What Wayne said. The fuse holders are on the load side of the switch component. So you can turn off the switch and replace the fuses without them being energized. And the extra barriers are supposed to keep you from contacting the still energized terminals on the line side of the switch component if you're a klutz or someone bumps into you.

Likewise, for panelboard type service equipment, any bussing or terminals on line side of the main breaker will now be covered or guarded. MLO panelboard service equipment is no longer allowed.
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Might be a stupid question but what if someone needs to clean the equipment while energized? Cleaning is a form of servicing.
 
Tainted said:
Might be a stupid question but what if someone needs to clean the equipment while energized? Cleaning is a form of servicing.
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I've never heard of people needing to clean live parts in panelboards or switchboards as regular maintenance or servicing. I mean if you really need to do that you de-energize it.

Perhaps we haven't been clear, but these new rules apply entirely to parts on the supply side of service disconnecting means. i.e. the stuff you can't turn off without the utility turning it off (or pulling the meter, if self-contained).
 
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