460/60HZ to 360V/60HZ
460/60HZ to 360V/60HZ
(OP)
How to convert a 3p/2HP/460v/60hz motor in applicaion 3p/2hp/360/60hz?
Motor needs rewind, is it?How to calculate the rewind date based on the original winding data?
Motor needs rewind, is it?How to calculate the rewind date based on the original winding data?





RE: 460/60HZ to 360V/60HZ
RE: 460/60HZ to 360V/60HZ
RE: 460/60HZ to 360V/60HZ
RE: 460/60HZ to 360V/60HZ
Connect them as open delta, auto transformer boost configuration. They will take 360 volts (240+120=360) up to 480 volts (240+120=120=480) and supply 4 amps. Your 2 hp motor should draw only a little more than 2 amps at 480 volts.
The transformers may be mounted at the motor location or the starter location, whichever is more convenient.
respectfully
RE: 460/60HZ to 360V/60HZ
Converting the winding for 360v operation is routine and straightforward for a competent shop. The original winding will have to be detailed and changes made to the wire cross-sectional area and number of turns per slot. For a drop in voltage it means less turns and an increase in wire CSA. The exact changes are arived at by means of a formula that all EASA member repair shops have access to. Note that full-load current will increase slightly after the conversion.
RE: 460/60HZ to 360V/60HZ
Drives with an active front end to provide power factor correction use a form of boost converter to develop a high DC bus voltage even from a relatively low AC input while still drawing a fairly good representation of a sinusoidal current from the utility. These drives can operate in the manner described, with a higher output voltage than the input.
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Sometimes I only open my mouth to swap feet...
RE: 460/60HZ to 360V/60HZ
RE: 460/60HZ to 360V/60HZ
I also think MotoDrv just read the application information backwards. We've all made minor errors like that, at least I have
place1234,
Where are you seeing a 360V 60Hz power supply? I don't show that on any of my charts for world industrial voltages.
Another option, if you do not already have the motor, is to find a 2HP 1 phase 208V 60Hz rated motor, because the Y voltage of 360V is 208 (assuming you have a 4 wire system of course).
JRaef.com
"Engineers like to solve problems. If there are no problems handily available, they will create their own problems." Scott Adams
For the best use of Eng-Tips, please click here -> FAQ731-376
RE: 460/60HZ to 360V/60HZ
I am agree with StarDelta. If you need the motor for 360 Volt the better choice is rewind.
Note:
Tn= New Turns per coil En= New Voltage(Desired)
To= Old Turns Per coil Eo= Old Voltage
Tn= To x En /Eo. This is true if the connection(delta or Wye), No.Circuits,Groups and Coils per Group remains constant. For 360 Volts The Turn ratio will be: 360/460 = 0.782 then the new turns per coil will be lower= 0.782 To, take account for the new 360 Volts motor will drain more Current(4.3 Amp) for it you most vary the Wire Size.(When the turns in a coil are changed, the wire size changes in order to provide the same slot fill) in this case will be greatest to support the new current.
The new Wire Size will be:
CMo=Old circular mil area, CMn = New circular mil area.
CMn = CMo x To/Tn then the CMn = CMo x To/0.782 To
= 1.278 CMo.
Best Regards
Petronila
RE: 460/60HZ to 360V/60HZ
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: 460/60HZ to 360V/60HZ
Is clear, Place is taking account the chance to rewind the motor and is asking about this practice. I think too this is best way, also is asking "How to calculate the rewind date based on the original winding data?".
Regards
Petronila
RE: 460/60HZ to 360V/60HZ
I am changing my vote to the transformer
Skip the rewind..
The transformer will enable the motor to remain a stock version, keeping costs lower than a custom version and a heck of a lot easier to replace when/if it fails.
RE: 460/60HZ to 360V/60HZ
Transformer and VFD is a effcient way to solve this problem. My question is rewind of this motor, is there any difficulty? See, in the case, there is one batch of these motors, say 1000 numbers, what is the solution? The solution is : rewind.
RE: 460/60HZ to 360V/60HZ
http://www.barks.com/eacurr.html
JRaef.com
"Engineers like to solve problems. If there are no problems handily available, they will create their own problems." Scott Adams
For the best use of Eng-Tips, please click here -> FAQ731-376
RE: 460/60HZ to 360V/60HZ
pulling a motor out... Sending it off to a shop... Getting it torn down... Stripped of windings.. Re-wound and coated... reassembling it... testing it... transporting it back.. reinstalling it(belts, gears, couplings.. etc., is going to be less costly than a few pallets of transformers purchased in bulk shipped one way??
Also the, "360V in 60Hz land", question has never been answered has it?
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: 460/60HZ to 360V/60HZ
With such numerous units, imagine 1000 motors... it's goes like a tricky decision for rewinding or hooking up with additional equipment like transformers or drives.
I'll go with rewinding but prior to send it to a rewinding shop. It is best to check the winding with a service provider's rewinder or technician to evaluate the winding for possible reconnection rather than complete rewinding.
RE: 460/60HZ to 360V/60HZ
I was assuming that the motors were not yet installed. Good point.
RE: 460/60HZ to 360V/60HZ
If I was looking to buy 1000 360V/60hz motors I would approach the different manufacturers to get a motor of the correct voltage and frequency without rewinding. There's got to be one out there that would accomodate this.
RE: 460/60HZ to 360V/60HZ
I am more curious about the 360 V/60 hz stuff. I am with Keith on this about this location of yours.
Oh, BTW, I am not with Keith about rewind since I feel lesser the components (however well-made, reliable etc. etc.), lesser the chances of faiure. (Sorry Keith )
I agree with Lionel also.
RE: 460/60HZ to 360V/60HZ
1. "My question is rewind of this motor, is there any difficulty?" : No
2. "there is one batch of these motors, say 1000 numbers, what is the solution?": Perform an economic study to know if is better rewind all motors or Install a new Three phase transformer capable to handle this 1000 Motor load (2.5 MVA??). In the case your choice is a new transformer what happeneed if the transformer fail? this will shut down all motors.By Reliability I think the better choice is rewind all motors because you can have two or three motors like spare parts.
Another alternative is to look the internal winding connection, If the motor is connected for 460 Volts in DELTA you could reconnect the winding for two wyes and the motor will works fine at 380 Volts, then you can use the 360 Volts motors because you will be only 20 Volts below the new voltage rated (380V): 5% less.
Regards
Petronila
RE: 460/60HZ to 360V/60HZ
RE: 460/60HZ to 360V/60HZ
Since the frequency remains 60 HZ, and If the very same orginal connection and circuits are left in the new winding (n), the original turns per coil (TPCo) will be reduced and the original conductor cross section area (Acuo)increased.
TPCn = TPCo*(360/460)= 0.7826*TPCo
Acun= Acuo*(460/360)=1.278*Acuo
RE: 460/60HZ to 360V/60HZ
If it was a single or a few, I would scrap them and install new motors with the correct data, rewinding is much too costly, at lesst in high wage countries.
Greetings Aksel.