Electric ac induction motor 50hz to 60hz?

[Poolworx]

Can a single phase single speed 1.5hp induction motor run on both 50 and 60 hz 115 volts

 

[James]

Generally speaking, yess most will run at 50 or 60Hz
is there a nameplate on the motor?

 

[Lucien Nunes]

But obviously at 17% different speeds. A 4-pole induction typically runs at 1725rpm on 60Hz but 1425rpm on 50Hz. Heat dissipation and maximum torque may be affected by running a motor designed for one frequency only, on the other frequency, due to the winding and capacitor reactances not being optimal.

 

[Poolworx]

Unfortunately I don't have the name plate I threw the motor away. I also read a 50hz operating on 60hz can cause the motor to stall

 

[Fazz711]

Unfortunately I don't have the name plate I threw the motor away. I also read a 50hz operating on 60hz can cause the motor to stall

Unlikely to stall.
You will get minor differences in torque and power but not enough to cause problems

 

[Poolworx]

So could i run this motor on 60Hz without any significant issues

1KW/1.5Hp
220V/1Ph/50Hz

 

[Lucien Nunes]

It depends what it's driving. The motor itself will usually be OK, so long as the load is still correct , although it will run 17% fast.

What might make the difference is whether it coupled to a load that is designed for 1425rpm that will then demand an increased torque at the higher speed. E.g. If it is coupled to a centrifugal pump, because the pump torque/speed curve is typically a close approximation to a square law, the pump might demand a torque increase of (60/50)² = 44% extra torque and therefore 73% extra hp, which might overload the motor unless it was generously specced for 50Hz operation.

Is this, in fact, a pump? Or what is the application?

 

[Poolworx]

It depends what it's driving. The motor itself will usually be OK, so long as the load is still correct , although it will run 17% fast.

What might make the difference is whether it coupled to a load that is designed for 1425rpm that will then demand an increased torque at the higher speed. E.g. If it is coupled to a centrifugal pump, because the pump torque/speed curve is typically a close approximation to a square law, the pump might demand a torque increase of (60/50)² = 44% extra torque and therefore 73% extra hp, which might overload the motor unless it was generously specced for 50Hz operation.

Is this, in fact, a pump? Or what is the application?

Yes it's a swimming pool pump

 

[Poolworx]

Alternatively I would have to buy a 50hz to 60hz solid state frequency converter?

 

[Lucien Nunes]

For a pump I think you would have to ask the manufacturers, or do some detailed calculations from the curves. The pump might put too much mechanical load on the motor due to the extra speed. I don't know about pool pumps but it is possible that there are different impellers for 1425rpm and 1725rpm versions of the same pump.

I would ask their advice before investing in an inverter drive.

 

[Poolworx]

For a pump I think you would have to ask the manufacturers, or do some detailed calculations from the curves. The pump might put too much mechanical load on the motor due to the extra speed. I don't know about pool pumps but it is possible that there are different impellers for 1425rpm and 1725rpm versions of the same pump.

I would ask their advice before investing in an inverter drive.

Are inverter drives costly

 

[Fazz711]

Are inverter drives costly

Not any more.
Can be had for just over £100.

 

[Fazz711]

Just had a Google and can now be had for just over £50.
They get cheaper and cheaper all the time.
I recently got a single phase to 3 phase one for an industrial pillar drill for £100.
Used to be considerably more than that.

 

[Poolworx]

How would I size one for this motor?
1KW/1.5Hp
220V/1Ph/50Hz
To run on 60Hz

1.25kva 220v 50hz input 60hz output
Thanks

 

[Fazz711]

How would I size one for this motor?
1KW/1.5Hp
220V/1Ph/50Hz
To run on 60Hz

1.25kva 220v 50hz input 60hz output
Thanks

Google the kw volts and vfd/vsd.
When you get it set the parameters to match the pump you have and the drive will do the rest.

 

[Fazz711]

Something like this.
Ebay UK number 265213284360
Slightly more than £50 but best going slightly more on the kw rating

 

[Poolworx]

Thanks Fazz711

Unfortunately it doesn't ship to usa however I found a similar one but it says "The input for this VFD is 1 or 3 phase, and the output is 3 phase. Should I be looking for one with Single phase output not 3 phase

 

[Poolworx]

This is the spec for the one I found

 

[Fazz711]

Thanks Fazz711

Unfortunately it doesn't ship to usa however I found a similar one but it says "The input for this VFD is 1 or 3 phase, and the output is 3 phase. Should I be looking for one with Single phase output not 3 phase

Yes look for single to single.
Either that or look for three phase pump.
Which would be more efficient.

 

[James]

I have never come across a decent single phase to single phase speed controller

if I was doing it, I would be Looking for a 3 phase motor and a single phase to 3 phase inverter

I could then buy a decent quality system and not have to worry about the effects of capacitors and how they interact with a vfd drive.

 

[Fazz711]

I have never come across a decent single phase to single phase speed controller

if I was doing it, I would be Looking for a 3 phase motor and a single phase to 3 phase inverter

I could then buy a decent quality system and not have to worry about the effects of capacitors and how they interact with a vfd drive.

That would be the way I would do it.
Three phase pumps are better quality and more efficient.
But you have to factor in the cost of new pump if you allredy have a good one.
Proper single phase to single phase are good enough to run a pump.
I understand not using cheap speed control they very rarely work well unless you spend decent amount on them

 

[Poolworx]

Forgive me if i butcher this but if the input voltage is 220 volts 50Hz and the output is 3 phase, im assuming the output voltage is 220 volts across phases and 60Hz. Could i not then feed the motor from 2 of the phases

 

[Fazz711]

Forgive me if i butcher this but if the input voltage is 220 volts 50Hz and the output is 3 phase, im assuming the output voltage is 220 volts across phases and 60Hz. Could i not then feed the motor from 2 of the phases

No don't think so as the unit will see an imbalance and shut down