Operating 50 Hz motor on 60 Hz using VFD
Operating 50 Hz motor on 60 Hz using VFD
(OP)
Can We operate a 50 Hz motor on 60 Hz using variable frequency drive (VFD)?
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Operating 50 Hz motor on 60 Hz using VFD
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RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
The voltage does matter though. The drive cannot create voltage that is not there, meaning that it is limited to the maximum line voltage. It can however provide any LOWER voltage than the line voltage.
Without further details we cannot help you more than that.
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: Operating 50 Hz motor on 60 Hz using VFD
400V/50HZ motor, 440V/60HZ VFD output control by pot full scale. Burn out motor winding, i suspected the motor over-voltage/over-frequency due to mis-configuration of VFD setting. Prior replacement of the motor, i set VFD output 400V/50HZ with pot full scale. Hope the setting will suffice motor lifetime..
Any thoughts?
"..the more, the merrier" Genghis Khan
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
is there any disadvantages ? If yes then Please Explain ??
RE: Operating 50 Hz motor on 60 Hz using VFD
Just as ScottyUK said above, unless your power supply voltage is raised above your 50Hz voltage the torque will drop with the increased speed over nameplate.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
As itsmoked and ScottyUK have mentioned, there are specifics involved that need attention not only to the equipment, but also to the nature and dynamics of the load attached to the equipment.
For example, as ScottyUK mentioned you need to increase the voltage at the same ratio as the speed in order to maintain the motor torque. But even if you DID increase the voltage, if your load is a centrifugal pump or fan, at 120% speed the PUMP will require 172% power (shaft kW) from the motor. But at 120% speed the motor power only increases to 120%, so unless your motor started off being more that 50% over sized to begin with, you will come up short and overload the motor. If you can't increase the voltage, it's even worse.
"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Operating 50 Hz motor on 60 Hz using VFD
To reach 120% speed, max motor torque must be at least 144% of rated torque (considering rated torque = pump torque at 50Hz speed).
RE: Operating 50 Hz motor on 60 Hz using VFD
If the load holds the speed to 1500 RPM with 60 Hz applied, that is a slip frequency of about 17% That's over a 700% overload.
In practice, with that much slip, the motor will develop more than rated torque and run faster than 1500 RPM, but you will still be in a serious overload condition.
If your protection settings allow this condition, then either the motor, the drive or both are liable to emit the magic smoke.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Operating 50 Hz motor on 60 Hz using VFD
A fan or centrifugal pump's power requirement depends on flow, not just on speed. Not every centrifugal pump or fan application has an unregulated discharge, nor is every pump or fan motor sized for full (flow) "run out". Many, particularly small ones, are operated quite far to the left hand side of the pump curve. The ones that require full run-out performance etc. obviously cannot have their speed increased meaningfully beyond their nominal operating speed.
Many other types of pumps (i.e. positive displacement types) are far less steep in their torque versus speed curve, and in fact the dominant sizing case for the motors for such applications is often the torque required at minimum speed.
As to "the magic smoke coming out"- that's where a VFD's 2nd function- as an overload and soft starter- comes usefully into play.
RE: Operating 50 Hz motor on 60 Hz using VFD
I know you said 'small' but remember in some industries anything which doesn't require an MV supply is considered 'small'.
There's a big difference in stresses on the rotor if you run a 4-pole machine at 100Hz compared to running a 2-pole machine at 100Hz. Many 2-pole machines won't be good for 100Hz operation, especially as the size increases, due to factors like mechanical strength, bearing limitations, balance accuracy, and so on. Some motors certainly are capable of operation at these higher speeds but it's not wise to assume without checking, especially with modern motors which are designed to meet their stated spec but often don't have much margin on it as manufacturers strive to cut costs to a minimum.
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
RE: Operating 50 Hz motor on 60 Hz using VFD
120% speed the PUMP will require 172% power, but if suppose motor torque is equal with PUMP required torque at rated, motor can't supply a higer torque than rated (suppose can increase voltage at 60Hz accordingly), so PUMP speed can't increase and don't require 172% power. At 60Hz, motor torque curve may intersect PUMP curve in unstable zone.
iop95 (Electrical)12 Oct 15 12:47
waross, it's true if motor have enough torque to accelerate pump at that speed, so will be in overload, but if don't have torque will go in unstable region
iop, you have mentioned 'unstable region' & 'unstable zone' many times. I have never heard of this. Would you please explain what & where this is?
www.KilroyWasHere<dot>com
RE: Operating 50 Hz motor on 60 Hz using VFD
Unstable region (zone) is between pull-up and max torque of IM curve.
RE: Operating 50 Hz motor on 60 Hz using VFD
1500 RPM is 83% of 1800 RPM, still above maximum torque.
The original question:Simple Answer; YES.
The question as it seems to be developed;
Can we run 50 Hz driving a centrifugal pump at 60 Hz.
Only if the motor is about 75% over sized at 50 Hz.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Operating 50 Hz motor on 60 Hz using VFD
http://yourelectrichome.blogspot.ro/2011/08/torque...
RE: Operating 50 Hz motor on 60 Hz using VFD
www.KilroyWasHere<dot>com
RE: Operating 50 Hz motor on 60 Hz using VFD
I have heard first time in school, 25 years ago. :)
https://books.google.ro/books?id=m5I003c-PmUC&...
RE: Operating 50 Hz motor on 60 Hz using VFD
www.KilroyWasHere<dot>com