wondering what kind of motor this is

[n0oxy]

Here is a video of a 240 volt vacuum used for duct cleaning, I'm wondering if anyone might know what kind of motor this is. It definitely does not sound like the universal motors that are used in most vacuums, it sounds more like a very large central air type blower motor and I think those are usually shaded motors but not sure. It's really interesting to hear the motor start up, in some ways it reminds me of the old spencer machines. Or maybe it is a universal motor but it doesn't really sound like one.
Mike

 

[tolivac]

Wacted the video-and with this link there are other Hypervac duct vacuum videos-there is one that explains these portable units well.The 240V one has a VFD drive that powers a 3Ph motor from a 240V household single phase source.A VFD drive can ramp the motor up slowly and gently so as to not blow breakers.The vacuum can run from a 30A,60A drtyer or stove outlet.A junction box is available from Hypervac where the vacuum can run from 2 opposing 120V 15A outlets.When I listened to the 120V units starting they have split phase cap start 120V induction motors like in your washer or dryer.I could hear the centrifical switch engage and disengage.No universal vacuum type motors here!Their truckmount has a B&S Vanguard V-twin gas motor powering the suction fan.

 

[madman]

Ooh vfd for 3 phase motor, that's neat. I wonder why it needed a 3 phase motor, as opposed to a capacitor start 240v motor...

 

[mike811]

Looks like typical dust collector motor. I used to work in the wood industry. Our motors in our dust collectors used to be 3 phase 3000 rpm with huge suction fan. Ducting for those were usually 8 or 6 inch.

 

[tolivac]

Capacitor start/run motors cannot be used on VFD drives.If the drive tries to run the motor at too low a speed-the centrifical switch and start winding will keep trying to engage.3 ph motors don't have start switches or caps.

 

[tolivac]

I dealt with woodshop dust collectrs as well-most are "direct air" that I used-the debris going thru the fan before the filter.One I used had the cyclone before the fan so the large debris wouldn't go thru the fine-only the very fine dust-that then went to the filter bags.The large debris went into a bin or barrel under the cyclone.I did like throwing wood blocks into the suction inlets on the direct air collector used in a school woodshop-made such a nice CLANG! as the block went thru the fan turned by a 7Hp motor-and the block reduced to chips!!!The fan on that unit had blades like a quarter in thick steel!Seemed like it would mulch anything it got ahold of.