Motor and heat

I purchased a dust control unit from a big box store. Ran it for two hours last night and worked great but - the motor was so hot I couldn’t keep my hand on it. I would expect the motor to be warm but not that hot.

Any thoughts please.

Suspected it wasn’t right.

Thank you

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Sounds like cavitation. Size and length of hose? How many Cfm? Let it run without a hose and see if it gets hot.

I’ll give that a try before I take it back. I have a 6ft x 2.5" hose on it but I put a vacuum attachment on the end of the hose which I’m certain restricted suction. I’ll check cfm after work.

Thank you

I bought the 4" line. The dust collector came with an attachment that coverts the “in” to a 2.5" hose mount but won’t fit in or onto the 4" tube. Picking up connection now that will. I need to save up for a suckit or inventibles option to attach to the machine.

I think you’re

going to find other problems with that motor.
I run a 2 1/2 hose from the boot all the way to the dust collector.
It runs for hours on end an barely gets warm.

Do you have an amp meter that you can connect to it?

With the host blocked, no air, it should pull the least amount of amps.
With the hose off and intake wide open, it will pull the most amps and can overspeed the motor and impeller.

If it isn’t pulling a lot of amps, and still getting hot, then I would say there is something wrong with the motor.
There should be a plate on the motor that lists the specs on it.

It’s a dust collector. And I can post a picture of the plate mounted on the motor once I get home.

My plan is to run it for an hour with the 4" hose connected. If it gets as hot as it did last night it’ll go back to be swapped out. I picked it up at Menards for $100 bucks. I believe the brand is Portal. Just like most Chinese products, it’s the luck of the draw.

you can make a dust collector blast valve from a 4in pvc t fitting to regulate suction while letting unrestricted flow into the system

Ran the motor with no hose attached for less than 10 minutes and it’s hot enough to make me pull my hand away. Replacing it tomorrow.

Box says 660 cfm.

With no hose attached the motor and impeller are maxing out so it is pulling max amps and will be hot.
It needs some hose and restriction on it. There is a balancing act between too open and too restrictive, but watching the amps is the best way to tell. I have a digital amp meter and vacuum gauges on both sides of my unit which tells me how it’s running. I know I have a leak now because the amps have risen with everything closed.

I would replace the unit anyway.

It’s best if you can get about 4’-5’ of straight pipe right into the intake and then your branches/hoses off of that. The straight pipe cuts down on turbulence and gets close to laminar flow.

I’d also recommend a cyclone or separator in front of the impeller if you can. It will catch a lot of the junk before it gets to the impeller. You don’t want the impeller eating pieces of wood, clamps, etc.

Used as it is intended and even working it a bit, It should not get as hot as you describe.
With all inlets to the impeller closed the motor would be working the least, that is with minimal load.

Once the impeller starts moving air, the load increases and the motor should warm accordingly, but not to the temps you mention.
This also appears to be a T.E.F.C. motor. Totally Enclosed Fan Cooled. It does not need air from the impeller for cooling. I would exchange it. It would cost less in time that it would to rebuild your shop after the fire.

Mine is a Grizzly 1 horse dust collector.
TEFC motor.

Thank you all for sharing your knowledge.

I’m swapping this unit out today and reevaluating how I’ll hook it up.

I would say your start windings aren’t dropping out, ie the centrifugal switch isn’t working.
Not worth digging into, just return.

Chalk this up to “you get what you pay for”. Replacement unit gets just as hot as the first. I hate taking stuff back but i wouldn’t feel safe running this longer than 15 minutes at a time. It’s at 200 degrees or more according to my calibrated hands. I’ll put the $100 bucks toward a better system.

I did learn quite a bit. Thank you for the help.

check out a harbor freight dust collector, I have heard many good things about them for the money. Better airflow too!

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If there is one around you they are having sales this weekend. I have a 25% off coupon for tomorrow only that I can email you if you don’t have one.

Try to vent to the outside if you can instead of into the bag. The bag/wanna-be-filter on those types of units can cause more harm because they are so open and can send the really harmful size particles into the air. A lot of people, if they can’t vent outside, replace the bag with a Wynn filter.

I started with a Grizzly DC I found on craigslist, added the bigger Dust Deputy, and vented outside. It worked really well for a one tool-at-a-time thing.

Thanks Patrick- I do have a harbor freight available. Need to go check coupons now. I’ll take this Menards system back today.