Disconnects

[jonny1982]

I have heard a lot of different opinions on disconnects. What is the rule on them? If the panel is in site, a certain amount of feet away, etc., are they not needed? Our they only needed on equipment with motors? If equipment is over a certain amount of amps, are they needed? Are they needed to be a certain amount of feet away from equipment they are servicing, or just in site? If the equipment has a disconnect built into, is another needed?

If a chiller has a disconnect inside of it built into control panel, is another needed on the outside of it to be able to shut it down without opening it up?

Thanks.

 

[hurk27]

I have heard a lot of different opinions on disconnects. What is the rule on them? If the panel is in site, a certain amount of feet away, etc., are they not needed? Our they only needed on equipment with motors? If equipment is over a certain amount of amps, are they needed? Are they needed to be a certain amount of feet away from equipment they are servicing, or just in site? If the equipment has a disconnect built into, is another needed?

There are exceptions to where the disconnect for a motor could be installed, it is required to be within site of the motor but the exceptions allow a lockable disconnect to serve the motor out of sight if 430.102(B) exception (a) or (b) are met:

(a) Where such a location of the disconnecting means 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

If a chiller has a disconnect inside of it built into control panel, is another needed on the outside of it to be able to shut it down without opening it up?

Thanks.

Here is what the NEC says:

440.14 Location
Disconnecting means shall be located within sight from and
readily accessible from the air-conditioning or refrigerating
equipment. The disconnecting means shall be permitted to
be installed on or within the air-conditioning or refrigerating
equipment.The disconnecting means shall not be located on panels
that are designed to allow access to the air-conditioning or
refrigeration equipment or to obscure the equipment
nameplate(s).

Exception No. 1: Where the disconnecting means provided
in accordance with 430.102(A) is capable of being locked in
the open position, and the refrigerating or air-conditioning
equipment is essential to an industrial process in a facility
with written safety procedures, and where the conditions of
maintenance and supervision ensure that only qualified persons
service the equipment, a disconnecting means within
sight from the equipment shall not be required. The provision
for locking or adding a lock to the disconnecting means
shall be installed on or at the switch or circuit breaker and
shall remain in place with or without the lock installed.

It allows it to be on or within the equipment, it also allows it to be out of site if it is lockable for industrial sights that use lock out and tag out procedures.

this was from the 2011 so be sure you read the requirements for the code year applicable to your area.

 

[jonny1982]

There are exceptions to where the disconnect for a motor could be installed, it is required to be within site of the motor but the exceptions allow a lockable disconnect to serve the motor out of sight if 430.102(B) exception (a) or (b) are met:







Here is what the NEC says:


It allows it to be on or within the equipment, it also allows it to be out of site if it is lockable for industrial sights that use lock out and tag out procedures.

this was from the 2011 so be sure you read the requirements for the code year applicable to your area.

So there is no 50' rule? It just has to be in site? Would the breaker in the panel qualify as the disconnect ? Do you know what article this is in the NEC?

thanks

 

[arcsnsparks98]

The 50' rule you are mentioning can be found in the code definition of 'in sight.'

 

[Jraef]

The 50' rule you are mentioning can be found in the code definition of 'in sight.'

Lol, looks as though you also noticed that there are several misuses of "site" and "sight" in this thread, which if interpreted literally, change the interpretations of the rules.

Example, "in site" could mean just somewhere at the facility which would be way too vague, so should have been "in sight" as pointed out. Then later "industrial sight" should be "industrial site". Industrial sight might make me think I have to have a vision inspection system installed at every disconnect!

Ok, that last one was a joke...:angel: