480 V 3phase dual winding motors help
480 V 3phase dual winding motors help
(OP)
I have a client that has 3 such motors. Two manufactored by Siemans-Allis and one motor by Newman electric motors Inc.
I wish to convert these motors from two stage (windings) to a vfd start and control. Is this possible and how would it be done.They motor drive positive displacement blowers.
I can not find the corporate office for either of the motor manufacturers. Does anyone have this information.
I wish to convert these motors from two stage (windings) to a vfd start and control. Is this possible and how would it be done.They motor drive positive displacement blowers.
I can not find the corporate office for either of the motor manufacturers. Does anyone have this information.





RE: 480 V 3phase dual winding motors help
If you applied a VFD to the 4 pole winding of this motor, you could duplicate the performance of the original two windings at the original speeds as well as operate it at any speed between.
There are two pitfalls to this approach. First, the motor may not be capable of operating at speeds below 600rpm without overheating. Second, the motor will (probably) not be constructed using inverter duty magnet wire or insulation, so it may not last very long on a VFD.
Anyway, this will give you an idea of what factors to consider. If you provide your specific motor data we can see if this applies to you as well.
RE: 480 V 3phase dual winding motors help
Siemens Energy & Automation Inc., Motors & Drives Div.
3333 Old Milton Pkwy
Alpharetta, GA 30005 USA
Tel: 513-841-3100
Fax: 513-841-3290
Assets: 50M+ ($50,000,000 - 99,999,999)
Activity(ies): Manufacturer
Description: Adjustable Speed Drives & Drive Systems; Static
Excitation Systems.
RE: 480 V 3phase dual winding motors help
RE: 480 V 3phase dual winding motors help
if this is the case all you have to do is parallel the windings. the vsd can now be connected across the motor terminals. any drive supplier can assist you from here.
kind regds.
RE: 480 V 3phase dual winding motors help
I believe this approach would be most common for a large fan with high inertia which creates severe starting duty.
Perhaps in your case it is the high starting torque demanded by the load which makes the starting duty severe from a motor heating standpoint?
RE: 480 V 3phase dual winding motors help
So, if this is the case, the question to answer if you want to upgrade the system is:
- do you want to upgrade your starter to a modern design of similar function?
- or -
- do you want to upgrade your system so that it is variable speed?
My guess is that you want a modern starter of similar function. If so, a solid state soft starter will accomplish that at less expense than a VFD. A VFD would only be desirable if you want variable speed operation of the blower.
RE: 480 V 3phase dual winding motors help
1. Do you happen to have model or type numbers, serial numbers, etc. from the nameplates?
2. The motors may also be soft started over y-delta soft starter.
RE: 480 V 3phase dual winding motors help
A reduced voltage starter is one that starts the motor with reduced voltage across the windings. The methods of accomplishing this include primary reactor, primary resistor, autotransfomer, part winding, wye-delta, and (of course) solid state starters.
The primary factor that distinguishes a 'soft start' from the other types of reduced voltage starters is the fact that a soft starter offers continuously variable voltage from start to full speed. Specifically, the starter begins at 0V (full frequency) and ramps the voltage up to full value (240V, 480V....) based on user selection of acceleration time. This is done using SCR's.
All other types of reduced voltage starter involve discrete steps in the voltage applied to the windings. In other words, the motor starts in steps beginning at, for example with a autotransformer starter, 65% voltage and 42% torque right away. After a fixed time delay, the starter switches to full voltage and full torque. Two steps...'half speed' and full speed. If you stand next to one starting, you will hear (and see on the ammeter) two distinct steps. It is possible for these types of reduced voltage starter to have more than two steps, but this is not common and is more costly for each step added. However, no matter how many steps you add, the result is that for each step the motor sees an step increase in voltage and as such has an inrush and a torque surge with each step.
A soft starter uses SCR's to ramp the voltage up to full value based on user settings for acceleration. The ramping of the voltage (and torque output) is continuous from 0V to full volts. If you stand next to one of these while starting, you will not notice steps in starting but will see a gradual increase in speed. This is the basis for the name "soft start".
RE: 480 V 3phase dual winding motors help
Models No.PE-21
SN 1-5141-lr46473-01 and 1-5141-lr46473-01
Type RGE
Design B
Service Factor 1.15
Frame 365T
460 VAC, 3 phase, 82 amps, 1775 RPM
The other motor is a 75 HP Newman Electric Motor
Model or Frame 4054U/DD3482BB
SN X.4440316
Design Class A
440 VAC 3 phase, 80 amps, 1770 rpm
I believe all three motors have a class F winding
Thanks for you kind assistance
Dave Sullivan
RE: 480 V 3phase dual winding motors help
Please clarify whether you desire a new controller to functionally replace the old one or do you want to change the method of operation for your sysem fom single speed to variable speed.
RE: 480 V 3phase dual winding motors help
As a matter of interest the motor speed (blower) will be a function of flow based on a 4 - 20 ma single with lower limits to assure that the system does not go below a minimum speed.
The existing system is just one speed but starts with a twi stage system that I believe is a low voltage system.
Thanks for all the kind assistance this forum is wonderful
Dave Sullivan