Air Comp plugged into wall outlet

[ContractorDave]

I have a couple of situations in a mine where riser mounted 3/4 hp compressors are supplying air for dry systems. They have cords installed and are plugged into wall outlets. The mine electrician doesn't seem bothered by this but it seems very unsatisfactory. Thoughts?

 

[stookeyfpe]

As long it is listed for fire protection service your installation meets NFPA 13. I've seen cord and plug electrical receptacles on samll air compressors used for DPVs.

 

[PEDARRIN2]

Forgive my ignorance, but I am not sure why this would be allowed unless the outlet is on an emergency power circuit.

If the power failed and the system lost air pressure, couldn't that cause a problem?

 

[ContractorDave]

A thanks to stookey for your continued support.
Thanks also PEDARRIN2 but my concern was more to do with what appeared to be a rather flimsy way to connect the compressor (which is part of a life safety system) to the power supply. Whether or not it is a part of an emergency circuit is not really a part of my purview, though I must ensure that the air supply is reliable. If this particular circuit goes down and is not noticed, the low air pressure signal still must indicate to the FAP and/or central monitoring station if low air becomes a problem.

Regards
Dave

 

[gouveia]

There are UL-Listed air compressors that must be hard wired. However, I do not believe that the code requires them. As stated, probably to not good practice. However, I don't blieve it is prohibited. I will have to check with some Elec Engineers to see if there is a NEC requirement.

UL Fire Protection Listing
UL File EX5324 - UL2125 Motor-operated air compressors
for use in sprinkler systems.

 

[Slowzuki]

Air-compressors are not required to be listed, you can grab air from the plant air supply or better yet instrument air.

The power supply isn't required to be supervised either. The client obviously would like the dry system to be reliable. No one wants busted pipe due to freezeups from accidental trips.

 

[JoeWill123]

Just from a practical stand point, it seems very reckless.

Joe G. Willett
Jacksonville, AR