Wiring air compressor

[speedshop]

Picked up a new compressor for the shop, 7.5hp single phase. I need help picking out what wire to order. It says #6 wire if under 50 ft or #4 if over 50 ft. I will be right at 60 ft from the breaker box. I have a 200 amp service and want to use wire that is in the flexible metal coving to avoid conduit. Suggestion on where to buy and which size? Example- would i need 6/4 or 6/3 etc.

Thanks for your help

 

[cvairwerks]

Probably better price it out first. #4 MC runs in the 6-7$ a foot range. May be cheaper to run conduit and change to flex were necessary.

 

[pattenp]

You need 3 conductors. 2 hots, 1 ground. The #6 is plenty.

 

[alfredeneuman]

May be cheaper to run conduit and change to flex were necessary.

in the flexible metal coving to avoid conduit.

EMT is approved for "protection against physical damage".
MC and AC cables aren't, and all flexible conduits aren't either.

 

[micromind]

It wouldn't bother me one bit to use 6/2 with ground for 100'.

 

[speedshop]

I will be running the cable on a steel beam 10’ up so not concerned about not being in conduit.

 

[mm08822]

Provide the motor nameplate and compressor nameplate.

 

[speedshop]

Provide the motor nameplate and compressor nameplate.

Here is the product page

7.5 HP Air Compressor, 2 Stage, V4, 1 Phase, 80 Gallon, Vertical, Silent Air System

Our 7.5 HP Air Compressor, with Silent Air technology, is built to exacting standards, designed to provide years of quiet, reliable service.

emaxcompressor.com

32 amp running
50 amp breaker

 

[wyliesdiesels]

Here is the product page

7.5 HP Air Compressor, 2 Stage, V4, 1 Phase, 80 Gallon, Vertical, Silent Air System

Our 7.5 HP Air Compressor, with Silent Air technology, is built to exacting standards, designed to provide years of quiet, reliable service.

emaxcompressor.com

32 amp running
50 amp breaker

motor circuits are sized by HP NOT running amps or nameplate amps

wire is sized by 125% of HP FLC table amps

for 7.5HP thats 40 x 1.25 = 50a rated wire. #8 THWN in conduit or 6/2 NM-b

breaker can be max 250% of FLC amps so 100a

will need to be hardwired. nema plug not rated for 7.5hp

will also need a disconnect if not within sight of and further than 50' from breaker panel

 

[wyliesdiesels]

I will be running the cable on a steel beam 10’ up so not concerned about not being in conduit.

how do you plan to secure the NM-b then?

 

[speedshop]

how do you plan to secure the NM-b then?

Metal strap and sheetmetal screw

 

[speedshop]

how do you plan to secure the NM-b then

motor circuits are sized by HP NOT running amps or nameplate amps

wire is sized by 125% of HP FLC table amps

for 7.5HP thats 40 x 1.25 = 50a rated wire. #8 THWN in conduit or 6/2 NM-b

breaker can be max 250% of FLC amps so 100a

will need to be hardwired. nema plug not rated for 7.5hp

will also need a disconnect if not within sight of and further than 50' from breaker panel

Thanks

 

[wyliesdiesels]

Metal strap and sheetmetal screw

metal strap is not the proper attachment for NM

 

[speedshop]

metal strap is not the proper attachment for NM

Ok zip ties will work

 

[mm08822]

EMT would work and look much better. You already have some on the wall.