230V/50Hz to 110V/60Hz converter?

[galapogos]

Hi,

I've just purchased a 1200W food processor with an induction motor from US that requires 110V, intending to use it locally where the mains supply is 230V/50Hz, thinking I could just get away with a high powered step down transformer. However, after researching, it seems that the motor might overheat due to the frequency difference.

Is there any affordable way of converting 230V/50Hz to 110V/60Hz?

 

[jedishrfu]

Here's a kind of answer. They suggest reducing the current thru the device by lowering the voltage to say 90 volts.

http://wiki.answers.com/Q/If_you_run_a_60Hz_appliance_on_a_50Hz_will_it_hurt_the_appliance

and this:

http://sound.westhost.com/articles/50-60hz.htm

 

[Windadct]

Also - how do you know it is an induction motor?

 

[galapogos]

Thanks jedishrfu. I actually read the 2nd link. It suggested that doing that would cause significant loss of power and possibly internal supply voltages that are no longer regulated though.

Windadct, I checked the product tech specs. The manufacturer however did not specify if the appliance would work at 50Hz.

 

[galapogos]

Can someone explain why using a 60Hz induction motor on a 50Hz mains supply will generate more current as the 2 links claim? I understand why the motor would spin slower as a directly correlated to the mains frequency, but I don't understand why it would draw more current.

Also, I'm assuming the current drawn by the motor also depends on the load? i.e. if my motor is rated at 1200W, it's not going to be drawing 1200W all the time, e.g. when it's just spinning in air with no load? Is that correct?

 

[Windadct]

Only asking because most appliances in this power range use a universal motor - which would be fine changing the frequency.

 

[Averagesupernova]

galapogos, an induction motor can be thought of as a type of transformer. When the frequency goes down so does the inductive reactance. This causes more current to be drawn even though there is not an additional load on the motor. Look up information on variable frequency drives for induction motors. You will find that maintaining a specific voltage to frequency ratio is important when reducing frequency. In your case I would think that intermittent use would not likely hurt your food processor. However, since you have to change the voltage anyway, you could reduce it a bit farther to maintain the voltage to frequency ratio. Be aware that it will not have the power it would have when run as intended and it may even stall when loaded heavily. I would take Windadct's advice and check to see if it is a universal motor. If so, your concerns over frequency are for nothing. Good luck.

 

[galapogos]

Hi Averagesupernova,

I'm pretty sure it's an induction motor as it says on the product specifications. fyi, it's a Breville BFP800XL food processor - http://www.brevilleusa.com/sous-chef-food-processor.html

So it seems that as long as I keep the V/f ratio the same, it should draw the same amount of current from the mains? i.e. my food processor expects 110-120V/60Hz, which works out to a V/f of 1.83-2. I should then provide it a voltage of 90-100V to maintain the ratio, at the expense of power?

I actually have a 600VA step down transformer at home that outputs 100V/50Hz. However, my food processor is rated at 1200W. Would it work if I don't load my food processor heavily? Also, if the food processor tries to draw beyond 600W, the transformer fuse should break for not being able to provide enough power to the appliance, right? I'm assuming the appliance won't be damaged for not getting enough power?

Thanks again.

 

[Baluncore]

You are over-thinking the solution to this problem without a sufficient foundation of fact.
Frequency is most unlikely to be a problem as the speed control need not be that precise.
Do NOT use a series resistor to limit the supply.
Get a transformer that is approximately 230VAC to 115VAC, use that as the supply for the processor.
The problem will then almost certainly be solved.

 

[galapogos]

Hi Baluncore,

Thanks for chipping in. I'd like to think that it wouldn't be a problem, but most sites I've seen calculates the additional current drawn to be much higher than the 17% difference in frequency. That's the "fact" for me. Do you have a better reason than "speed control need not be that precise"? I'm all ears. Thanks.

 

[Baluncore]

You could run it on a lower voltage to correct for the frequency difference. I have never had a problem running 60Hz equipment on 50Hz and I have sorted out many peoples buying mistakes.

Without full specifications and the circuit details it is not possible to sufficiently analyse the situation. You must either stop building fear, uncertainty and doubt on a foundation of sand, or you must take the first step by plugging it in with a transformer and measuring the current.

 

[Baluncore]

The Australian version appears to be the Breville Kitchen Wizz Pro. Same part number BFP800. It has a four blade cutter while the USA version has only a two blade offset cutter. You will need to check up on the differences.

An optimum solution might be to sell your USA "Sous Chef" on eBay and buy the original Australian designed 220-240V "Kitchen Wizz Pro".

 

[galapogos]

Thanks again Baluncore. It would not be very feasible trying to sell a 110V appliance in a country that supplies 240V, nor ship it to a country that supplies that due to the weight/bulk of the item, but thanks for the suggestion.

Just a few more questions:

I have a 600VA, step down transformer that supplies 100V. My processor is rated at 1200W. If I do not load the processor heavily/at all, is it possible to test it with the transformer? I'm assuming that the fuse in the transformer would blow if current requirements exceed what the transformer is rated for, and the attached transformer will not be damaged?

Also, how would I measure the current? With something like a Kill-A-Watt?

 

[Ed Smith]

Here's a kind of answer. They suggest reducing the current thru the device by lowering the voltage to say 90 volts.

http://wiki.answers.com/Q/If_you_run_a_60Hz_appliance_on_a_50Hz_will_it_hurt_the_appliance

and this:

http://sound.westhost.com/articles/50-60hz.htm

Just got a kitchenaid pro 600 stand mixer its a USA 110v 575W motor.
The seller here in Thailand provides a 1KW 220v to 110v transformer.
There is a speed sensor & control board in the mixer.

There are plenty of auto ac voltage stabilisers here & I am sure that I can get one with 110v output but should I worry about the HZ & if so what can I do to get as close as possible to what the machine expects.
I am sure that I could adjust the 110ac up or down a bit.

Also would ac filter caps help on the 110ac output as it has 10 speeds & the auto speed sensing.

I am keen to know as it seems a hard job to make 60hz
Ed

 

[Ed Smith]

You are over-thinking the solution to this problem without a sufficient foundation of fact.
Frequency is most unlikely to be a problem as the speed control need not be that precise.
Do NOT use a series resistor to limit the supply.
Get a transformer that is approximately 230VAC to 115VAC, use that as the supply for the processor.
The problem will then almost certainly be solved.

Hi, Can you read my recent post and advise me?
Ed

 

[NascentOxygen]

Just got a kitchenaid pro 600 stand mixer its a USA 110v 575W motor.
The seller here in Thailand provides a 1KW 220v to 110v transformer.

You are implying that Thailand's power is 50Hz?

If you are listening to a nearby portable radio, does the mixer create major static?

 

[Ed Smith]

Correct, here in Thailand its 220vac 50hz... sort of , I have seen upto 238vac on my Drantz tester

 

[NascentOxygen]

There was a second question.

 

[no_alone]

What do you think will happen if I use this product which support 120V/60Hz:
https://www.oxo.com/oxo-on-9-cup-coffee-maker
in Europe with a power converter (from 230V to 110V but still 50Hz instead of 60hz)
Thanks.

 

[Baluncore]

What do you think will happen if I use this product which support 120V/60Hz:

Voltage converters usually have a 2:1 ratio so you would get 230V : 115V. There is plenty of tolerance to voltage variation so the voltage should not be a problem.
There is a 5% chance that frequency might be a problem. I therefore predict a 95% chance it will work OK.

 

[Planobilly]

When I moved from the United States to France we ran many U S devices on step down transformers without issue. That does not prove that your device will work but I don't see trying it with with a transformer as being a big risk.

Billy

 

[rbelli1]

Get rid of it and buy a food processor that matches you power system. Make sure it has a proper switch and no computer inside. I can almost guarantee that the computer will fail long, long before any of the mechanicals get even close to being slightly worn. Why must everything be computer controlled? At least it's not "In the cloud" and reliant on a server in China.

BoB

 

[jim hardy]

What do you think will happen if I use this product which support 120V/60Hz:
https://www.oxo.com/oxo-on-9-cup-coffee-maker
in Europe with a power converter (from 230V to 110V but still 50Hz instead of 60hz)
Thanks.

I think it will make fine coffee
but the clock probably uses power line for its time base
if so it will only advance 50 minutes every hour, losing 4 hours per day
so you'll have to plan ahead when setting your morning brew timer

and if these "perfectly timed cycles" use the same clock ,

Water is pumped to the brew basket in perfectly timed cycles,

you will get 1.2X the number of cups as you selected, so beware of overflow

that's what i think

Have some fun and try it out !

old jim
EDIT after thinking on this

the coffeemaker probably rectifies the line voltage to power the computer
simple power converters just chop line voltage to reduce rms, leaving a high peak
that's okay for heaters and motors

but it may well very shortly wreck the computer's power supply as suggested by Mr rbelli

there's a small chance they used a universal power supply that'll run on 230 volts but you're taking a chance, you'd have to open it and look

so i revise my thought.

I think it will likely let the smoke out of the computer board.