convert 50Hz equipment to 60Hz?

I am trying to figure out how, or if I need to convert a 50Hz drying machine
for use on our 60Hz system. If so, is there a change I need to make to the
machine or something I need to install in the power supply?
Thank you
Shane
Reply to
Shane Manley
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Do you want to be a bit more specific on what you mean by a drying machine? They come in all shapes and sizes and for drying a wide range of things - from a 10MW silo grain drier down to a 5W nail varnish drier.. I guess, with a name like "Shane" it won't be one of the latter??
Basically, most electrical driers consist of a heating elements - which mostly won't care whether it gets 50Hz or 60 - together with a motor driving an air circulation device; the motor may care. There may be a control unit which uses the line frequency for timing, so that may care too.
It may be worth seperating out the supply for the heating elements and driving them from 60Hz. Then use a 50Hz inverter or UPS to drive the motors and control electronics.
Ideally, from here you would re-post with the make and model of the drier, together with any details off any of the motor(s) inside. A link to a circuit diagram of it would help....
Of course some drivers use natural convection and are basically just a heater with an isolator. They can run off practically anything, without worries.
Reply to
Palindr☻me
Check the motor and controls for acceptance to 60 cycles, the heating elements will not care.
Power supply ya right, your talking about an motor generator set if this is going to run for long.
Reply to
SQLit
Thank you.
It's a clothes drier.
If I were to seperate the control and heating power in order to add an inverter why not just add a larger inverter for the whole machine?
Shane
Reply to
Shane Manley
Thanks.
Being a clothing drier, the machine will run intermittently for about 1/2 to 1 hour at a time.
From what I gather, it seems I should just get and invertor for the whole thing anyway. How are inverters sized- by current draw?
Shane
Reply to
Shane Manley
Because the heaters wiill draw a lot of power, and high power inverters are expensive.
This thing is probably driven by an induction motor, with a belt drive to the drum. Induction motors run at sliightly less than synchronous speed, which for a four pole motor (the most likely) would be 1500 rpm for 50 Hz, and 1800 rpm for 60Hz. The speed of the motor in ths case would be something liike 1450 rpm, and this would rise to something like 1740 rpm on 60Hz.
The motor wndings would draw slightly less current at the higher frequency due to their iinductance. It's unlikely that the motor would have any problems with 60 Hz, but the speed of a clothes drier is fairly critical; too low and the clothes will just roll around in the bottom of the drum; too high and they will stick to the drum and be carried right around with it. At the correct speed they will be carried up by the drum until they are close to its highest point, and then fall back down.
The 20% speed increase may be enough to prevent this from happening. The drum is obviously rotating at a much slower speed than the motor, and the reduction is probably done via a belt drive, in which case you could probably correct the speed by a change of pulley, unless they've used some strange non-standard components, and you can't get a pulley to fit. Changing the motor won't help with the speed, you won't be able to get an induction motor which runs just a bit slower than the one you have.
The heaters will work ok on 60 Hz.
The controls probably will.
Nobody can give you a defiinite answer to your question wiithout knowing exactly what components your machine contains, but is unlikely to have any problems wiith 60Hz., other than running slightly faster.
Even going the other way, using 60Hz. equipment on 50Hz., where inductiive components will draw a greater currect, seldom causes problems. I have several transformers marked for 120V 60Hz. whiich I am using on 50Hz. wiithout problems. The difference in frequency isn't very great, it's not like you're trying to use 400Hz. aircraft equipment on an old 16 2/3 Hz. raiilway.
Look for frequency ratings on the individual components of your machiine. If you can't find any, contact the manufacturer for advice.
There may however be other issues to consider. Where in the World are you? Is this domestic or industrial equipment? Single or three phase? What country was it designed for? What Voltage? If it's single phase, and 50 Hz, then it's most likely designed for 220/240V. If you're on 60 Hz., then you're most likely in the USA or Canada, assumiing that you're not in parts of Japan.
Be aware that US and Canadian 240V supplies are not like those in most 50Hz. countries; the US system has two live (hot) conductors with a central neutral, 120V from either live to neutral, 240V between the two lives. In most 50Hz. countriies there is a single live conductor at 240V from the neutral. There could be safety implications with single pole switches/breakers/fuses if the machine has them. If you had been going the other way, using a US type machine on a European type supply you could have serious problems, as the machine could well be expecting to find 120V for small loads between one live conductor and neutral; something whiich it certainly wouldn't find in the European system.
If the Voltage is incorrect you could use an auto transformer to step it up or down, but one rated for this sort of load would be large, heavy and expensive.
If this is an industrial three phase machine, things get far more compliicated; there are major differences between three phase supplies in different countries.
Lastly, if your machine works, which it quite likely will, then it may well not comply with the electrical regulations in your country. Manufacturers have to make slightly different versions of basically the same machine for different markets. Sometimes these differences are at the whim of the government, but sometimes there are good underlying reasons for them. For example, British plugs have to contain a fuse, while those in America and mainland Europe do not. The reason for thiis is that British 13A sockets are wired on a ring main, fused at 30A, and therefore each appliance needs a fuse in the plug to protect its flex, which will not be able to carry this much current.
Reply to
furles
Based on experience, I'd say that a 220/230 volt 50Hz clothes dryer will work on US 240 volt 60Hz power without modifications. The drum does turn about 20% faster, so that clothes stay against the outside of the drum instead of tumbling. If it has a motor-driven timer, that will also run 20% faster, and a 30 minute setting will be done in 25 minutes. The heating elements don't care about frequency, and if they run hotter on the higher voltage the thermostat will compensate with shorter "on" times.
That dryer only lasted a few more years anyway, after the previous owner brought it over from the UK years earlier then left it when he sold the camp. I still have the motor saved for future projects...
Mike
Reply to
Mike Lamond
The motor torque will be reduced by the lower current, but the loading will be higher because of the faster drum speed (providing the cloths are tumbling down and not stuck to the drum all the way round), so you should reduce the maximum weight loading by at least 20% (theoretically by nearer 40%, but you'll probably get away with a 20% reduction).
Reply to
Andrew Gabriel
Absolutely not! The heating elements use a huge amount of power - you do not want to buy an inverter sized for the wattage used. You'd be better off just buying a new machine, rather than buying an inverter that could power the existing machine. As others have stated, an inverter for that kind of power would be expensive.
I think you'll be fine running on 60 hz. Your timer will likely be off, so you'll probably need to fudge factor that.
Reply to
ehsjr
Check to see if motor is rated for 50/60 hz, if not replace it with a 60 hz version and change pulley size to maintain correct speed.
Reply to
D.Miller
Oh come now. I'm sure you can find a more expensive way to run your $100 clothes dryer. I suggest special ordering a 50 Hz diesel generator set.
Price out an inverter, price out a new clothes dryer...and do the math.
Bill
Reply to
Bill Shymanski
What bad thing will happen if you run the 50 hZ motor on 60 hZ?
Reply to
ehsjr
Often, the load increases more rapidly that speed. Thus, the motor may end up overloading itself. With reasonable protection as a watchful eye (and sensitive hand) during the first few hours of operation you can determine whether the motor is running too hard for its own good.
Reply to
John Gilmer
Covered already in the thread.
Reply to
Andrew Gabriel
You guys are too much };-) Ha Ha
Connect it to a 50Hz Diesel Generator ? };-)
I Gather this is Not Meant for Use in the USA we have Standards so people wo't have to hassle with these matters, just enjoy yor purchase.
I'd plug it in a let it whirl away .....
Standard Industry appliances are rated 10-20% under tolerance so Use It and change the Motor to a US Rated same torque & Model but only when & if it Burns out, the coils won't mind the extra sizzle., it's only finer rather than faster juice.
Reply to
Roy Q.T.
Yes, I know. I wanted D. Miller's thoughts. He's recommending a new motor, not me. Let's find out why.
Reply to
ehsjr

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