Garbage disposal commercial kitchen

hhsting

Senior Member
I have 120V 800va single phase garbage disposal installed in restaurant commercial kitchen under sink.

Disconnect is fused at 20A for the garbage disposal provided by designer.

Questions:

1. Assume the fused disconnect is on the sink counter. Should not one need 3 feet working space per NEC 2017 section 110.26(A)?

2. Assume the fused disconnect is under sink then would disconnect be in compliance with NEC 2017 Section 110.26(E) and 110.26(A) or not?

3. What code section of NEC 2017 require garbage disposal to have disconnect?


Please all tree questions in NEC 2017
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
1. A disposal never gets a fused disconnect. We install a snap switch and that's it
2. The disposal is under the sink so why would the disconnect not be acceptable there. Again not fused but a standard snap switch
3. 422.30 and 422.31
 

hhsting

Senior Member
1. A disposal never gets a fused disconnect. We install a snap switch and that's it
2. The disposal is under the sink so why would the disconnect not be acceptable there. Again not fused but a standard snap switch
3. 422.30 and 422.31
Right but on the plans designer indicated fused disconnect.

If the designer is providing fused disconnect then where in NEC 2017 it says disposal never gets fused disconnect just a snap switch?
 

Greentagger

Senior Member
Location
Texas
Occupation
Master Electrician, Electrical Inspector
I have 120V 800va single phase garbage disposal installed in restaurant commercial kitchen under sink.

Disconnect is fused at 20A for the garbage disposal provided by designer.

Questions:

1. Assume the fused disconnect is on the sink counter. Should not one need 3 feet working space per NEC 2017 section 110.26(A)?

2. Assume the fused disconnect is under sink then would disconnect be in compliance with NEC 2017 Section 110.26(E) and 110.26(A) or not?

3. What code section of NEC 2017 require garbage disposal to have disconnect?


Please all tree questions in NEC 2017
1. Yes
2.Probably not unless its a big enough sink to comply with 110.26
3.422.31(B)
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
IF you provide a fused disconnect as the disconnecting means, 110.26 would apply but not 110.26(E) as it is for panelboards, switchboards, etc.
IMO, 422.31(C)would apply
 

hhsting

Senior Member
Its 3 comp sink in commercial kitchen. If the fused disconnect is under the 3 comp sink and one bend under the sink to get to the fused disconnect then 110.26(A) would be in compliance if their is 3 feet in front correct? I assume it would not be in compliance top of sink.

Also the fused disconnect under the sink nema 3R ok or has to be higher?
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
The fused disconnect has to be within sight from garbage disposal.

Would it be considered within sight if the fused disconnect is located next to the sink while garbage disposal is under the sink?
What sort of commercial kitchen sink unit you have? Most I've seen are open, just 4 SS legs secured to floor, no cabinet. So most anywhere in the same room might be within site.
 

hhsting

Senior Member
Fuse sizing for garbage disposal disconnect is also not in 422.11(A). It refers back to 240.4 and 240.4(G) table refers back to part II of 422.

What NEC 2017 section one uses to size fuse for garbage disposal disconnect?
 

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
Its 3 comp sink
Again those sinks usually have no cabinet, open underneath. Most locations within room maybe within sight.
Fuse size for the garbage disposal disconnect i dont see it in NEC 2017 422?
Sizing is dictated by motor/mfg and wire size as is most equipment. What does mfg cut sheet or name plate speciations indicate? 422.11(G), 422.30, 422.31, 422.33, or 422.34(D) and consider 422.35
 

hhsting

Senior Member
Again those sinks usually have no cabinet, open underneath. Most locations within room maybe within sight.

Sizing is dictated by motor/mfg and wire size as is most equipment. What does mfg cut sheet or name plate speciations indicate? 422.11(G), 422.30, 422.31, 422.33, or 422.34(D) and consider 422.35
422.31(C) says disconnect means must be within sight or capable of being locked in position. Exception to 422.31(C) is 422.34(D) for other occupancies

So according to 422.34(D) branch breaker if ready accessible can be disconnecting means provided disposal has unit switch.

So one can comply with 422,31(C) Or 422.34(G) but not both? This means branch circuit breaker if ready accessible does not have to be lockable provided disposable come with unit switch? However most garbage disposal don’t come with unit switch?
 
Last edited:

Fred B

Senior Member
Location
Upstate, NY
Occupation
Electrician
422.31(C) says disconnect means must be within sight or capable of being locked in position. Exception to 422.31(C) is 422.34(D) for other occupancies

So according to 422.34(D) branch breaker if ready accessible can be disconnecting means provided disposal has unit switch.

So one can comply with 422,31(C) Or 422.34(G) but not both? This means branch circuit breaker if ready accessible does not have to be lockable provided disposable come with unit switch. However most garbage disposal don’t come with unit switch
422.34 in 2017 has no (G) but 422.34(D) is listed in 422.31 as an exception to the requirements of 422.31(C), that doesn't mean you can't comply with both just you don't have to if conditions of exception can be met.
One extra consideration is most disposals or a lot of them are plug in. If that is the type being used, the cord and plug is the disconnect. I have had 2 that had motor mounted service switch. Found it once on service call for a disposal not working, HO hit switch that was "hidden", (rotational placement of disposal unit) on back of disposal with normal storage stuff under sink.

Overall most of this discussion is speculations of might be or could be. Without knowledge of mfg specifications all is just an exercise of code possibilities, get mfg specs for the appliance and size and design to specs.
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
Overall most of this discussion is speculations of might be or could be. Without knowledge of mfg specifications all is just an exercise of code possibilities, get mfg specs for the appliance and size and design to specs.
Exactly.
Commercial garbage disposals can vary from fractional HP to 3 & 5 HP units some with factory controllers. Without specifics all our answers are speculation.
 

Rock86

Senior Member
Location
new york
Occupation
Electrical Engineer / Electrician
Right but on the plans designer indicated fused disconnect.
Is the design specifically calling for a fused disconnet, or do they have a disconnect sysmbol indicating the electrical contractor is to provide a means of disconnect? Did the designer call for fuse sizes?
 
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