Can I VFD this motor

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jaceon

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indiana
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tech
I have an exhaust fan that we've installed, wired 480 3 phase. The boss wants it to basically have two speeds so it doesn't have to run full speed all the time.
I've never messed with VFD's, and the tag doesn't mention VFD. I guess I'm just not positive what all's possible with this particular motor?

Also I don't know how to attach a picture or I could attach the actual name plate but here's some of the basic info.

Teco 2hp/60Hz 460V, 3A, 1170rpm, Code L, S.F.1.15, Nom Eff 88.5, Min Eff 86.5, Design B
Type AEHH8P, ENCL TEFC, Rating Cont, INS F, Phase 3, AMB 40C, DE BRG 6306ZZ, ODE BRG 6306ZZ
"Useable ON V network AT"
 
charlie b

charlie b

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This may or may not be possible. You can't just take any motor and power it via a VFD. It has to be compatible with that type of power source. You need to have a conversation with the motor's manufacturer.
 
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paulengr

Senior Member
Yes. Almost any VFD. The trouble is there is a really steep learning curve with VFDs. I’d rather you start out with something more advanced like a Teco E510 or Schneider ATV312 but the Lenzse/AC Tech drives are particularly simple.

The “inverter duty” rating on motors is a way of pushing distance. All that it means is they added phase paper and maybe slightly thicker insulation to the motor coils. Beyond about 50 feet between VFD and motor you can run into an electrical issue called reflected waves which can destroy a motor. Using an inverter duty motor extends this limit to around 200 feet. After that point you really need to add a dV/dt filter to extend it to over 1000 feet. Or a line termination network at the motor end does the same thing.

VFDs are deceptively simple. They work really well mist of the time. The programming can be very intimidating, ctoo. Because normally we all learn to check what every setting and button does in case it causes problems later. With drives this isn’t practical. Use the defaults unless you have problems. Keep the VFD under 50 feet away and run a separate ground between the motor frame and the VFD frame. That is really all there is to it
 
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winnie

Senior Member
Location
Springfield, MA, USA
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Electric motor research
Supposedly this motor _is_ VFD rated,
www.mrosupply.com

Teco-Westinghouse NP0052 AEHH8P MAX-PE HP: 5 RPM: 3600 FRAME: 184T

The NP0052 is produced by Teco-Westinghouse and is described as a Teco-Westinghouse NP0052 AEHH8P MAX-PE HP: 5 RPM: 3600 FRAME: 184T
www.mrosupply.com www.mrosupply.com

but paulengr is right on target. You can run just about any 3 phase induction motor with a standard VFD, with a bunch of caveats. The benefit is that you will be able to adjust speed over a wide range, and especially for fan applications can save quite a bit of energy.

The caveats read like the list of possible side effects on a medication. If you run the motor too slowly it won't get enough cooling and will overheat (likely not a problem with a fan load, since torque also drops as speed drops). Because VFDs 'switch' at high frequencies, you can see effects that cause more voltage stress on the windings (the reflected waves mentioned), which can reduce motor life. You can also see current that gets capacitively coupled through the bearings reducing bearing life. Etc. Etc.

-Jon
 
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jaceon

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Location
indiana
Occupation
tech
Hey I appreciate the insight. I was hoping for some confidence that this would even work before getting to deep into it, and ya'll have been really helpful with that.
The panel that powers the fan is about 120 feet away, but I could easily mount a VFD within 30 feet. I've worked around VFD's in our cranes, but never really understood them, so it would do me good to learn these things.
Thanks again
 
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paulengr

Senior Member
jaceon said:
Hey I appreciate the insight. I was hoping for some confidence that this would even work before getting to deep into it, and ya'll have been really helpful with that.
The panel that powers the fan is about 120 feet away, but I could easily mount a VFD within 30 feet. I've worked around VFD's in our cranes, but never really understood them, so it would do me good to learn these things.
Thanks again
Click to expand...

Bypass the contactor. Don’t start/stop VFDs this way. You can set up a VFD with say a start and stop button or just an on/off switch and also either fixed speeds like a selector switch or use two buttons (faster/slower) to cycle several presets, OR use a speed pot. Just some examples of typical built in features.
 
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jaceon

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Location
indiana
Occupation
tech
Before I return this ATV312 as junk (bought used) just wanting to confirm with some of you VFD intelligent folks that there's not some secret switch used to turn off the display or something else I'm overlooking. All I have hooked up is the ground, L1, L2, and L3 to my supply and the red load light is all I get. controls/display seem dead....
16043518177260.jpg
 
GeorgeB

GeorgeB

ElectroHydraulics engineer (retired)
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Greenville SC
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Retired
I assume you have read the manual, I haven't ... I ASSUME it is not good to apply power without a motor connected. Red LED may just mean no load connected?
 
ptonsparky

ptonsparky

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Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
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I’m sure we’ve powered up VFDs at the shop to program the basic parameters and set up control, no load. We only have 480 via a back fed single phase xfmr, and single phase 240. Both will run a 1-1/2 hp 3 ph fan. Is it a good idea for the 480, probably not. The shop 240 VFD is designed for it.
 
ActionDave

ActionDave

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ptonsparky said:
I’m sure we’ve powered up VFDs at the shop to program the basic parameters and set up control, no load. We only have 480 via a back fed single phase xfmr, and single phase 240. Both will run a 1-1/2 hp 3 ph fan. Is it a good idea for the 480, probably not. The shop 240 VFD is designed for it.
Click to expand...
We never had 480V set up at our shop. Had a three phase delta service. Old 15kva wired up backwards knocked the voltage down to 120V for checking out motors. Even with the leads made up 480V you could start 50hp motor.
 
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jaceon

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Location
indiana
Occupation
tech
I did skim the connection part of the manual, and have tried it with and without load connected. Since it sounds like I'm not missing anything, I'm just going to return this guy and try another fella. Appreciate you guys taking time to discuss
 
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jaceon

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Location
indiana
Occupation
tech
Just as a follow up, that VFD was bad. Got a different one that was good and setup was a piece of cake. Appreciate the help.
 
kwired

kwired

Electron manager
Location
NE Nebraska
ptonsparky said:
I’m sure we’ve powered up VFDs at the shop to program the basic parameters and set up control, no load. We only have 480 via a back fed single phase xfmr, and single phase 240. Both will run a 1-1/2 hp 3 ph fan. Is it a good idea for the 480, probably not. The shop 240 VFD is designed for it.
Click to expand...
Done that as well, even tested out some operational things with no motor connected at times. I do seem to recall those Schnieder drives will return a fault code if it doesn't detect a connected motor, might be a parameter that can disable that feature though.

Also seem to recall them having little or nothing on the display when not in run mode, and no faults to display. Might been how it was programmed for the application? Ones I run into the most are on a grain dryer and are already setup on the equiment, I just have had to play with them a little bit when servicing, I hate their display, not very bright and hard to read in outdoor locations on bright sunny days.
 
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paulengr

Senior Member
kwired said:
Done that as well, even tested out some operational things with no motor connected at times. I do seem to recall those Schnieder drives will return a fault code if it doesn't detect a connected motor, might be a parameter that can disable that feature though.

Also seem to recall them having little or nothing on the display when not in run mode, and no faults to display. Might been how it was programmed for the application? Ones I run into the most are on a grain dryer and are already setup on the equiment, I just have had to play with them a little bit when servicing, I hate their display, not very bright and hard to read in outdoor locations on bright sunny days.
Click to expand...

You can run pretty much any VFD without a motor. Programming wise any of them. To “run” it needs to be in V/Hz mode only (vector does not work for obvious reasons...no feedback current). There is usually a fault code you need to disable as well. This is a standard feature. Drives on 3 contactor bypass systems will fault if the output contactor switches. Same with the input (line) side which also usually allows single phase operation.
 
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