Dust Collector

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Dennis Alwon

Dennis Alwon

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Suppose you have a dust collector that is rated 19amps, would you consider this an appliance or a motor. If the nameplate states 19 amps must I add 1.25 for the motor load?

The reason I ask is because of 422.10(A)- first paragraph. They talk about motor oper. with no nameplate but not one with a nameplate. Normally I would think 125% needs to be added but this seems to give leeway
 
Dennis Alwon said:
Suppose you have a dust collector that is rated 19amps, would you consider this an appliance or a motor. If the nameplate states 19 amps must I add 1.25 for the motor load?

The reason I ask is because of 422.10(A)- first paragraph. They talk about motor oper. with no nameplate but not one with a nameplate. Normally I would think 125% needs to be added but this seems to give leeway
Click to expand...

Most of the time the nameplate already includes the 125%.
 
Also the second paragraph in 422.10(A) had me going since it stated 430 for motor operated appliances without a marked rating. This made me think if it were a marked rating then 430 didn't apply-- I knew that didn't seem correct.

Someone had asked me today and I was conflicted but I kept saying "But it is still a motor so 430 should apply".
 
Does this dust collector have as part of the machine a motor controller, switches, safety switches, other limits, and/or any other aux loads associated with the dust collector, and a nameplate that includes data for all the devices combined? If answer is yes it is likely an appliance - although it is still a motor operated appliance.

If it just has a motor, maybe safety switches or other limits - but they need to be field wired, as well as motor controller and other control devices need field wired then you have a motor circuit and possibly a motor control circuit and nothing in 422 applies. JMO.
 
It is one complete unit for a residential wood shop. No name tag info. available at this time, other then 19 running amps. But mostly the question is does it have to be wired at 125% of running amps.?
 
Michael15956 said:
It is one complete unit for a residential wood shop. No name tag info. available at this time, other then 19 running amps. But mostly the question is does it have to be wired at 125% of running amps.?
Click to expand...
That is the million dollar question. If it is an appliance it will depend entirely on what the nameplate says, if it is just the nameplate of the motor itself, and we are indeed installing a 430 motor circuit, then we must apply 125% of the values in tables 430.247-430.250 and not the FLA marked on the motor, unless it is a special motor not included in the tables. Chances are greater of it being an appliance if it is a special rated motor that is not in the tables.
 
Well according to Michael it is rated 3.5 HP which is not in the table but I don't see why 125% would not count based on the art. Michael stated--422.3
 
I'm confused NEC 2008(if still the same in 2011) says appliance motors shall comply with 430,,,,,,,,,,,,,,430 says it will be at 125%.

dick
 
Michael15956 said:
Where in 430? Is it in the note at the bottom of Table 430.22(E)?
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First sentence in 430.22 is the general rule for continuous duty single motor applications.

There are other places where 125% is required depending on whether the circuit or feeder is supplying single or multiple motors, motors and other loads, different types of motors, continuous or non continuous duty motors. All those different situations also would apply to a motor driven appliance as 422.3 directs us to art 430 for motor operated appliances, and to 440 for appliances with hermatic refrigerant compressors, but there are also some sections in 440 that send you back to 430 also.
 
Dennis & Kwired, the question is: is this motor operated appliance (dust collector) considered continuous or other than continuous duty? Section 430.22(E) states if "Other than Continuous Duty" it does not need to be wired at 125%.
 
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