Converting frequency on US devices (60Hz - 50Hz)

Thread Starter

classic1984

Joined Sep 1, 2017
4
Hi guys, I need some assistance on using small US devices designed to operate at 60hz. I'm in the UK (50Hz/220v) trying to use US clippers. Because of the frequency difference, the volt transformers alone don't work. The clippers become loud and violently rattle.

Some say the solution is an AC to 12v DC converter and a DC to AC 110/60Hz car Inverter as seen below.
http://www.buythebest10.com/wp-content/uploads/2015/09/6101v4Z8YML._SL1000_.jpg


Are these methods accurate, as in an identical function as 120/60hz mains? I've heard some say that you need a pure sine wave, but most reviews seem good.

Just needed to make sure. Appreciate any assistance.

Thanks.
 

MrChips

Joined Oct 2, 2009
30,706
As far as I can tell, without having prior experience, that appears to be the logical approach, i.e. use a 12VDC to 110VAC/60Hz inverter.
 

dendad

Joined Feb 20, 2016
4,451
You could try lowering the voltage to say, 90V.
The current through the internal coils may be to high, and they could be saturating as the frequency is lower.
I have come across American equipment the had 220V rated transformers that overheated in Oz as the frequency is lower even though the voltage was ok.
 

Thread Starter

classic1984

Joined Sep 1, 2017
4
Thanks for your input guys. I have $500 worth of equipment, and if the DC converter+inverter set up in the videos works, that's like $45, so it might be worth pursuing.

Technically Is there any reason for it not to work?
 

DickCappels

Joined Aug 21, 2008
10,153
(Some text and media removed for clarity)

I've heard some say that you need a pure sine wave, but most reviews seem good.
(Some text removed for clarity)

Technically Is there any reason for it not to work?
(This is an opinion because I have not performed the necessary experiment) Yes. Some inverters put out a pretty crummy approximation of a sine wave. The more "square" the waveform the higher the magnetizing current which creates the force that makes your clippers vibrate. For the best experience find an inverter that has a clean sine wave output.
 

Thread Starter

classic1984

Joined Sep 1, 2017
4
So I went with this set up..

Converter
https://www.maplin.co.uk/p/12v-5000ma-car-accessory-socket-ac-dc-power-supply-l25ay

Inverter
https://www.amazon.com/gp/product/B06W9NMXVZ/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

The clippers will only switch on maybe 70% of the time. The inverter red light will often show. I think the issue is converter related as I've since tried another converter (below), matched up the Bestek inverter and the clippers fare even worse. They cut great, when they'd manage to switch on.

https://www.amazon.co.uk/gp/product/B07125GXGY/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I've been warned about 'cheap' converters made in china, so maybe that's the issue. Other than that, I can't think of a reason why this wouldn't work. The converters have more than enough capacity for my devices.

Any help greatly appreciated.
 

dendad

Joined Feb 20, 2016
4,451
A lot of devices have a start surge current that is much higher than the run current so that is most likely your problem.
Try running the inverter from a car battery for a test and see if the clippers start reliably. If so, you need a bigger 12V supply.
If not, it looks like a bigger 110V inverter is the answer.
 

#12

Joined Nov 30, 2010
18,224
The inverter red light will often show.
Seems to me that the start surge is tripping the overload safety. (dendad got here first.)
I think I'm grateful he's here because he can do most of what I can do on this site.

I have an idea that placing an inductor in series with the load will suppress the start surge and encourage the wave form to be more sinusoidal. You might even tune the inductor to 60 Hz with a capacitor. The size and quality of these components is impossible to calculate without a current rating provided. If you were a designer, I would suggest a transformer with a low voltage, high current output and place that winding in series with the load. The primary winding could then be tuned to 60 Hz, but you aren't a designer.:(

You approach is valid. You are only working on the details now.
 

#12

Joined Nov 30, 2010
18,224
On a side note, is frequency really an issue at all here, or just voltage?
Frequency is almost the entire problem, and I only said, "almost" because somebody can surely think of an exception, no matter how trivial.
 

xox

Joined Sep 8, 2017
838
Frequency is almost the entire problem, and I only said, "almost" because somebody can surely think of an exception, no matter how trivial.
Ah, sorry I overlooked your preceding post! But surely certain devices aren't so sensitive to such minor differences in frequency, or are they?
 

#12

Joined Nov 30, 2010
18,224
Ah, sorry I overlooked your preceding post! But surely certain devices aren't so sensitive to such minor differences in frequency, or are they?
The differences are not minor. Almost everything European has difficulty with American designs.
 

#12

Joined Nov 30, 2010
18,224
I don't know why the U.S decided on 60 Hz, but it sure caused a dichotomy that resulted in a million problems.:mad:
 

dendad

Joined Feb 20, 2016
4,451
I think those clippers will be mechanically resonant at 60Hz. Often they are not a motor but an electromagnetically driven core that is linked to the blades. Hence the need for 60Hz.
 

Thread Starter

classic1984

Joined Sep 1, 2017
4
I just noticed the converter I posted in the first link. Upon reading some of the reviews, many people are complaining about intermittent power and not being sufficient enough to power their device, which pretty much seems like my problem, so maybe the issue is the product and not necessarily the proposed setup. Many use similar inverters for the same purpose so I don't think it's that.
 
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