Grey area in NEC 430 Clarification requested

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RWZIMM

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I have run across a rather grey area in the NEC that I would like to get some clarification on. I have a MCC unit with starters that control the roof top fan systems and other motors around the plant. Under the new 2008 NEC 430.102(A) it requires disconnects within site of the motor being controlled and the controller. The exception reads that you do not need a separate disconnect for the controller if the controller is lockable.
So my question:
Am I required to provide a separate means to disconnect power to the
motor within line of sight of the motor if my starter or disconnect in the main gear that supplies the branch power to that motor is lockable and the facility has a written lock out tag out procedure?

Example: 480V 3 Phase Rooftop fan does not have a disconnect or controller on the roof or within sight of the roof top fan motor, but it is supplied with a Starter Bucket in the MCC that can be locked in the open position and the facility has a written lock out tag out procedure.

I have always thought I was required to provide some means for disconnecting power to the fan unit within line of sight of the motor whether it was a lockable controller or lockable disconnect.

Thanks
 
Welcome to the forum.

Look under 430.102(B). The exception allows for the DS not being required to be in sight if you have a lockable controller (which you do) and you meet the criteria for either of expections (a) & (b). It sounds like you may be able to justify it under (b) if indeed only qualified persons are going to service the equipment.
 
I guess it's a judgment call, and I seldom have to confront it, but I would be hesitant if "the facility has a written LOTO procedure". To me, the exception requires a little more than that.
I've been fortunate that the only time I have seen the motor disconnect omitted, the industrial facility has a strict, supervised procedure and trained personnel.
 
By the way, this is not new for the 2008 NEC, it was added to the 2002. Some minor changes in 05 and 08, the big change for 08 is the language that the lock means must remain in place.
In an industrial facility with trained electricans and a good LOTO program, it may be possible to omit the disconnects.

But for a commerical location, I would not. You will force workers to work hot. the idea of the disconnect is to make it easy to LOTO.
 
And I want to add this rule does not seem gray at all. The exception only applies to industrial facilites.
 
Definitly agreeable. I was not suggesting that he stretch rule to avoid using the disco, but the exception is there and I definitly think it's valid. In a lot of industrial setting that I see nowadays older MCC remain in operation while new mechanical units are added that usually include unit mounted VFD controller which provide disconnects pretty standard so it's becoming less of an issue.

tom baker said:
And I want to add this rule does not seem gray at all. The exception only applies to industrial facilites.
Click to expand...
 
Thanks for the help with this issue as this information provided pretty much matched my own but it is good to get a second opinion. I still am not too comfortable with omitting these disconnects within sight of the fan motors since they are on the roof and the MCC room is a long way away. And well just how good or how much can you rely on an owner adopted LOTO procedure?
 
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