Motor Disconnect Required?

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Horton said:
NEC 2008 430.102 (2) exception permits motor installation WITHOUT disconnect AND out of sight of controller if the controller is properly installed AND has capability of locking the motor circuit open with the locking mechanism remaining attached to the controller.
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In order to use that exception you must meet the requirments of either 430.102(B)Exception (a) or (b). Depending on the installation that may not always be that easy.

430.102(B) Motor. A disconnecting means shall be provided for a motor in accordance with (B)(1) or (B)(2).
(1) Separate Motor Disconnect. A disconnecting means for the motor shall be located in sight from the motor location and the driven machinery location.
(2) Controller Disconnect. The controller disconnecting means required in accordance with 430.102(A) shall be permitted to serve as the disconnecting means for the motor if it is in sight from the motor location and the driven machinery location.
Exception to (1) and (2): The disconnecting means for the motor shall not be required under either condition (a) or condition (b), provided the controller disconnecting means required in accordance with 430.102(A) is individually capable of being locked in the open position. The provision for locking or adding a lock to the controller disconnecting means shall be installed on or at the switch or circuit breaker used as the disconnecting means and shall remain in place with or without the lock installed.
(a) Where such a location of the disconnecting means for the motor is impracticable or introduces additional or increased hazards to persons or property
(b) In industrial installations, with written safety procedures, where conditions of maintenance and supervision ensure that only qualified persons service the equipment
FPN No. 1: Some examples of increased or additional hazards include, but are not limited to, motors rated in excess of 100 hp, multimotor equipment, submersible motors, motors associated with adjustable speed drives, and motors located in hazardous (classified) locations.
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You are correct, sir

You are correct, sir

I was pointing out to those stating that the disconnect MUST be within sight that they were mistaken. Fortunately most of our customers have written safety policies that per the NEC allow us to install motors without disconnects.
 
Horton said:
NEC 2008 430.102 (2) exception permits motor installation WITHOUT disconnect AND out of sight of controller if the controller is properly installed AND has capability of locking the motor circuit open with the locking mechanism remaining attached to the controller.
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Horton said:
I was pointing out to those stating that the disconnect MUST be within sight that they were mistaken. Fortunately most of our customers have written safety policies that per the NEC allow us to install motors without disconnects.
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Despite the statements in the NEC, the OP has stated he requires compliance with both the NEC and the NFPA79.

The main panel disconnect has restrictions on location. It can be used even if out of sight of the machine provided it fulfills all the motor disconnecting requirements of the NEC and his industrial shop has written safety procedures.

Otherwise under the NFPA79:2007:5.3 the motor disconnect is an isolation device that must be within sight of both the motor and the machinery that might move. There is no exception under the NFPA79 for written safety procedures.
 
Horton said:
I was pointing out to those stating that the disconnect MUST be within sight that they were mistaken.
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There are very, very few times when a motor disconnect can be out of site of the motor.

The exception uses the word impracticable which essentially means imposable.

So if you have submersible pump motor it would be impracticable to have the disconnects in site.

Impracticable is not the same as impractical which is how many people like to read the exception.
 
iwire said:
We went down this road before and I showed you how the people who write the code feel about it.

I cannot help if you do not agree with them, perhaps you could put in a change proposal?
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It is not a question of agreeing or not, it is a question of what reality is and reality is that nearly without exception industry install what I described AND it meets the NEC.

But i have no problem of shutting down entire industries if that is what you prefer, or not to be able to build anything as it is not cost competitive. We are on our way to out-legistlate and out-regulate the US from the market. As Khrushcev said, following Lenin: we will sell them the rope they will use to hang themselves.
 
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iwire said:
We went down this road before and I showed you how the people who write the code feel about it.

I cannot help if you do not agree with them, perhaps you could put in a change proposal?
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bob -

I can only guess you are not speaking of industrial.

Because, speaking of industrial only, (2008) 43.102.B.1, 430.102.B.2, Ex to (1) and (2), has not substantually changed in the last 40 years - although I can not verify more than twenty years of that (1990).

My personal exposure during the last 40 years (guessing several thousand motors), I only remember six that had local disconnects - that was a jet fuel pumphouse at an airport.

I must have missed it when you "went down this road before and I showed you how the people who write the code feel about it"

These un-named people certainly did not write their feelings in 430.102. The exception is absolutely clear and is the industry standard. (edited to add) No change proposal is needed. The code reads exactly as it should

So it isn't a case of disagreeing with them or you. That premise is just simply wrong.

cf
 
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Cold Fusion said:
bob -

I can only guess you are not speaking of industrial.

Because, speaking of industrial only, (2008) 43.102.B.1, 430.102.B.2, Ex to (1) and (2), has not substantually changed in the last 40 years - although I can not verify more than twenty years of that (1990).

My personal exposure during the last 40 years (guessing several thousand motors), I only remember six that had local disconnects - that was a jet fuel pumphouse at an airport.

I must have missed it when you "went down this road before and I showed you how the people who write the code feel about it"

These un-named people certainly did not write their feelings in 430.102. The exception is absolutely clear and is the industry standard. (edited to add) No change proposal is needed. The code reads exactly as it should

So it isn't a case of disagreeing with them or you. That premise is just simply wrong.

cf
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Having spent nearly 15 years of doing nothing but HVAC/BAS Control Systems I rarely see a disconnecting means within sight from the motor. Between MCC's, VFD's, and RTU's you are almost always near the motor but cannot see it.
 
Common industry practice: Written safety procedures and motor disconnects for the facility out of sight of the motor. NEC exception applies.

NFPA79 restriction applies to industrial machinery only, not the facility. Industrial machinery motor disconnects must be within sight of both the motor and the driven machinery.
 
iwire said:
There are very, very few times when a motor disconnect can be out of site of the motor.

The exception uses the word impracticable which essentially means imposable.

So if you have submersible pump motor it would be impracticable to have the disconnects in site.

Impracticable is not the same as impractical which is how many people like to read the exception.
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Bob,
There are two exceptions to this rule...the one you are talking about and the one that permits the remote lockable controller disconnect to be used as the motor disconnect with written safety procedures. This applies to most industrial occupancies. I rarely see an industrial installation where the motor disconnect is within sight of the motor, unless the routine operations require that the motor be locked out. In this case, where routine cleaning or things like that require that the motor be locked out, the disconnect is often at the motor because having the point of lockout at the motor speeds up the process.
 
don_resqcapt19 said:
Bob,
There are two exceptions to this rule...the one you are talking about and the one that permits the remote lockable controller disconnect to be used as the motor disconnect with written safety procedures. This applies to most industrial occupancies. I rarely see an industrial installation where the motor disconnect is within sight of the motor, unless the routine operations require that the motor be locked out. In this case, where routine cleaning or things like that require that the motor be locked out, the disconnect is often at the motor because having the point of lockout at the motor speeds up the process.
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One word: Meltric. Look it up....:)
 
pfalcon said:
Common industry practice: Written safety procedures and motor disconnects for the facility out of sight of the motor. NEC exception applies.

NFPA79 restriction applies to industrial machinery only, not the facility. Industrial machinery motor disconnects must be within sight of both the motor and the driven machinery.
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weressl said:
One word: Meltric. Look it up....:)
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Meltric appears to qualify for NFPA79:2007:5.5.5(4) and 5.3.2 although I didn't see the listing posted.

don_resqcapt19 said:
Bob,
There are two exceptions to this rule...the one you are talking about and the one that permits the remote lockable controller disconnect to be used as the motor disconnect with written safety procedures. This applies to most industrial occupancies. I rarely see an industrial installation where the motor disconnect is within sight of the motor, unless the routine operations require that the motor be locked out. In this case, where routine cleaning or things like that require that the motor be locked out, the disconnect is often at the motor because having the point of lockout at the motor speeds up the process.
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I mention NFPA79 since the OP says his shop has adopted it. If this application is industrial machinery and not the facility then the remote lockable controller disconnect must be within sight of the machine and the driven machinery due to NFPA79:2007:5.3,5.4,5.5

If the application is the facility or they had not adopted NFPA79 then I don't see an issue for an industrial shop with written safety procedures being out of sight.
 
pfalcon said:
...
I mention NFPA79 since the OP says his shop has adopted it. If this application is industrial machinery and not the facility then the remote lockable controller disconnect must be within sight of the machine and the driven machinery due to NFPA79:2007:5.3,5.4,5.5

If the application is the facility or they had not adopted NFPA79 then I don't see an issue for an industrial shop with written safety procedures being out of sight.
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It is my opinion, based on the scope of NFPA 79, that it never applies to anything installed by the electrician...it only applies to the industrial machine as built by the manufacturer.
 
don_resqcapt19 said:
It is my opinion, based on the scope of NFPA 79, that it never applies to anything installed by the electrician...it only applies to the industrial machine as built by the manufacturer.
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And any changes made to that machine,
NFPA79:2007:1.3.1.1 ... the changes shall conform ...
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NFPA79:2007:1.1.1 ... commencing at the point of connection of the supply ...
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with no exception granted for who actually built, installed, assembled, or changed the machine. So to break down your statement:

Applies only to an industrial machine :: YES
as build by the manufacturere :: NO - 1.3.1.1 says any additional changes shall conform. No exclusion is made for it not being the manufacturer that makes the change.

Just like the NEC, it covers what it covers with no exclusion for who worked on the equipment. The two scopes cover the manufacturer, the contractor, the factory owner, and the DIY homeowner.
 
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