What wiring do I need for my new dust collector?
#1
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What wiring do I need for my new dust collector?
I just assembled a new Grizzly 3hp dust collector.
The manufacturer recommends a 40a circuit, but I have checked around and everyone runs them on 30a circuits without any problems.
The plate says it draws 22a, Grizzly says it is 20a, and I measured it at 19a. I also measured the starting amperage as 140a; and started it repeatedly without incident on a 30a breaker. Square D says a 30a breaker will handle 150a for 4 to 12 seconds without tripping, and the DC only draws 140a for a split second before dropping down to 19a.
I can either put a plug and outlet on it, or hardwire it. It is 15' to the panel, so figure 25' of cable; not much voltage drop.
My understanding is that if I hardwire it I can use#12 wire (1.25*18A, which is below the max of 25a for #12) and a 40a breaker (2.25*18a). So, my plan would be to run #10 romex to a junction box and a #12 whip to the switch box; all on a 30a breaker. Is that okay?
Is MC okay for the whip, or do I need something more substantial? What is acceptable.
I think those values would not be acceptable for a plug/outlet. What would I need there? Would 30a all the way be okay?
Thanks
The manufacturer recommends a 40a circuit, but I have checked around and everyone runs them on 30a circuits without any problems.
The plate says it draws 22a, Grizzly says it is 20a, and I measured it at 19a. I also measured the starting amperage as 140a; and started it repeatedly without incident on a 30a breaker. Square D says a 30a breaker will handle 150a for 4 to 12 seconds without tripping, and the DC only draws 140a for a split second before dropping down to 19a.
I can either put a plug and outlet on it, or hardwire it. It is 15' to the panel, so figure 25' of cable; not much voltage drop.
My understanding is that if I hardwire it I can use#12 wire (1.25*18A, which is below the max of 25a for #12) and a 40a breaker (2.25*18a). So, my plan would be to run #10 romex to a junction box and a #12 whip to the switch box; all on a 30a breaker. Is that okay?
Is MC okay for the whip, or do I need something more substantial? What is acceptable.
I think those values would not be acceptable for a plug/outlet. What would I need there? Would 30a all the way be okay?
Thanks
#2
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It sounds like a 30 amp circuit would be fine as long as it is dedicated to the dust collector.
#6
Is the suggestion for a 40 amp circuit in the manual? Have you called and talked to them directly? Perhaps it is a misprint. Sounds like 30 amps should do it no problem.
I like to connect all my machines with a plug. That gives me more flexibility in my shop to move things around.
I like to connect all my machines with a plug. That gives me more flexibility in my shop to move things around.
#7
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Nope, not a misprint. I called and they confirmed it. Now... all the guys in tech support know is how to read the manual, so if it is a misprint they would probably just repeat what is in the manual.
Shop Fox, a sister company, uses the same motor in a somewhat different unit and calls for 30a.
I suspect someone occasionally has a substandard 30a breaker that trips on startup, so to CTA they call for a 40a.
Shop Fox, a sister company, uses the same motor in a somewhat different unit and calls for 30a.
I suspect someone occasionally has a substandard 30a breaker that trips on startup, so to CTA they call for a 40a.
#8
The plate says it draws 22a, Grizzly says it is 20a, and I measured it at 19a.