Current / Watts Drawn by Ultrasonic Cleaner

Does anyone know how many input mains (110V or 220v) watts are used a typical 3 transducer ultrasonic cleaner (with and without a heater function)?

I know the output ratings are typically 200 -300W for the transducers and 300W for the heater but that does not tell me how large of a step-up transformer I would need to operate a 220V cleaner on 110V mains input.

I have found a good deal on a ultrasonic generator that can operate multiple frequency transducers but it is 220V input and I don't know if my 110V to 220V 300W step-up transformer will be up to the task.
 
Mine is 180/300 watts. Heaters are 100% efficient - it's really easy to turn power into heat. The transducers operate at a fixed frequency, so there's no reason they should be less than 85% efficient. I expect you need 500 watts if you're going to run both, 5 amps at 110v, 2.5 amps at 220v.

Your step up should be fine if you don't use the heater, or if you use it before putting in the records, then turn it off when you turn on the ultrasonics.

Most people think the record cleaner should operate at 75-85 degrees. You probably keep your house at 68 so you could just skip the heater entirely. There's no reason to think hotter water works better. You can use a low temperature surfactant, like any good dishwasher rinse aid. You could couple that with enzymes, like rocco & roxie. The dishwasher rinse aid will do the same job as alcohol so there's no reason to use alcohol, which is not particularly good for your vinyl.

You can get a 6l ultrasonic cleaner on ebay for $85. I've looked into making a DIY ultrasonic cleaner and I don't see how to do it cheaper than China does.

If your wife complains, tell her it will also clean her jewelry. In my experience that turns the complaints into an instant smile. It's all presentation with women - 100%.
 
Last edited:
Caveat- I'm not suggesting Alconox for record cleaning, though I have used it. What they say about temperature is interesting-
Temperature for Ultrasonic Cleaning

As for power, I don't know the power factor for ultrasonic cleaners but can imagine it might not be great, save for the heater, which is purely resistive. I'd go slightly oversize on the step-up if possible, about as suggested above.
 
Mine is 180/300 watts. Heaters are 100% efficient - it's really easy to turn power into heat. The transducers operate at a fixed frequency, so there's no reason they should be less than 85% efficient. I expect you need 500 watts if you're going to run both, 5 amps at 110v, 2.5 amps at 220v.

Your step up should be fine if you don't use the heater, or if you use it before putting in the records, then turn it off when you turn on the ultrasonics.

Most people think the record cleaner should operate at 75-85 degrees. You probably keep your house at 68 so you could just skip the heater entirely. There's no reason to think hotter water works better. You can use a low temperature surfactant, like any good dishwasher rinse aid. You could couple that with enzymes, like rocco & roxie. The dishwasher rinse aid will do the same job as alcohol so there's no reason to use alcohol, which is not particularly good for your vinyl.

You can get a 6l ultrasonic cleaner on ebay for $85. I've looked into making a DIY ultrasonic cleaner and I don't see how to do it cheaper than China does.

If your wife complains, tell her it will also clean her jewelry. In my experience that turns the complaints into an instant smile. It's all presentation with women - 100%.

Thanks. I think you are correct on all counts.

I have spent all week doing research on ultrasonic cleaners. The specs I have found show that a 300W generator (transducer driver) uses 1-2 amps. So, my 300W step-up transformer should be adequate for that. As you said, the heater is another story all together.

I found a 300W, 40KHz, 110V cleaner for $89 delivered. Can't beat that price. To build one from parts would be about $300 - $400. On the other hand, if you want to try any frequency other than 40KHz, it becomes a push.

I have decided to go all in and am going to buy the the 40KHz unit off the shelf and also build one that can operate at 40/80/120KHz. It will probably be summer before I get it built.

I'll post the results of using one frequency 40, 80, or 120KHz and various combinations of the 3 frequencies on records in different conditions: "from not well cared for" to "looks like new" condition. I'll probably also compare using multiple frequencies and some method of manual pre-cleaning.
 
The smallest features on a record are about 3 microns.

40khz has a wavelength of 36mm. 120khz has a wavelength of 12mm. These waves are 10,000 times the size of the small features. It's interesting that they work so well. A wave that fits in the groove is about 100 microns, which is about 12mHz. A wave which gets into the features is about 120mHz. My intuition is that the cleaners would have to work at lots of megahertz, but apparently they're just fine at 40khz.

I've read a couple places that 80khz doesn't work as well as 40, but by all means try it and report back. The definitive test is to have several dirty records. Clean one at 40khz, one at 80, one at 40 then 80, one at 80 then 40, and compare the sound.
 
Last edited:
The groove is not cleaned by the wave propagation, it is cleaned by the cavitation bubbles when they collapse. In order for cavitation to occur, there does need to be a minimum distance between xducer and record (> ½ wavelength IIRC). The size of the bubbles are inversely proportional to the frequency and the energy released is directly proportional to the size of the bubble, so higher frequencies will create smaller bubbles but will not be as aggressive (lower frequency cavitation can etch metal). The smaller bubbles will also be more evenly distributed and higher qty than larger bubbles which prevents "hot spots".
 
The smallest features on a record are about 3 microns.

40khz has a wavelength of 36mm. 120khz has a wavelength of 12mm. These waves are 10,000 times the size of the small features. It's interesting that they work so well. A wave that fits in the groove is about 100 microns, which is about 12mHz. A wave which gets into the features is about 120mHz. My intuition is that the cleaners would have to work at lots of megahertz, but apparently they're just fine at 40khz.

I've read a couple places that 80khz doesn't work as well as 40, but by all means try it and report back. The definitive test is to have several dirty records. Clean one at 40khz, one at 80, one at 40 then 80, one at 80 then 40, and compare the sound.

From what I have read so far:

The primary ultrasonic cleaning effect is caused by the implosion of tiny bubbles. This "cavitation" effect does not require the bubbles to actually penetrate into the grooves. When the bubbles implode, they in effect suck debris out of the grooves. At lower frequencies the bubbles are larger and implode more forcefully than at higher frequencies. Because of this, a 28KHz transducer is actually capable of eroding the stainless steel cleaner tank and would probably damage a record.

A 40KHz frequency is known to be safe for records at least in the short term. However, there seems to be some debate as to whether higher frequencies might remove smaller particles that are deeper in the groove and also leave less cleaning residue behind.
 
At lower frequencies the bubbles are larger and implode more forcefully than at higher frequencies. Because of this, a 28KHz transducer is actually capable of eroding the stainless steel cleaner tank and would probably damage a record.

A 40KHz frequency is known to be safe for records at least in the short term.

Here's the rub: The "40kHz" machine may not actually run at 40kHz. I measured a commercial record cleaner with 40kHz transducers and it ran at 35kHz. The individual transducers were designed for 40kHz, but none of them had their resonant frequency at 40k (see first plot below). When lumped together in parallel, there was no resonant peak at all, the impedance just dropped with lower frequency (second plot). As far as I could tell, they adjusted the frequency until the power consumption equaled the rated 200W (if I dropped the frequency further, I could get 350W consumption), although power consumed does not equate to sonic power produced. As with any tuned circuit, maximum efficiency is achieved when the generator frequency equals the resonant frequency of the load.

I have the Degritter USRCM and the transducers appear to be hand matched (they all had the exact Fr written on each one and they were all very close). When measured in parallel, there was a definite dip in impedance at 120kHz so the load is well matched to the amplifier driving it. They also sweep the frequency around 120kHz to ensure all 4 xducers are working at max efficiency.

From what I've read on the audio blogs, these US devices are not well understood, either by the users or the mfrs. The cheap cleaning tanks for auto parts and jewelry are just that, cheap attempts to use a technology that is vastly more complex than it appears. Most of the 40kHz machines that are not made specifically for record cleaning should be used with hearing protection. While you cannot hear the sound waves coming from the tank, the SPL can be dangerously high and has the ability to damage your hearing.
 

Attachments

  • 40kHz Impedance.jpg
    40kHz Impedance.jpg
    122.3 KB · Views: 90
  • 30-40kHz Phase.jpg
    30-40kHz Phase.jpg
    128.6 KB · Views: 84
Last edited:
I just found this. It is a paper on ultrasonic cleaning that covers almost all that is necessary for a basic understanding of the process. I cannot link to it though because the link just downloads a PDF. Do a Google for "fundamentals of ultrasonic cleaning". Look for the result that is the same and includes "Extreme-Macro". It was second on the results list after People Also Ask when I found it.

It seems weird because you will also see "cleaning insects" but the PDF has nothing to do with bugs. LOL
 

PRR

Member
Paid Member
2003-06-12 7:04 pm
Maine USA
www.diyaudio.com

Attachments

  • ultrasonic-cleaning.pdf
    431.3 KB · Views: 11
  • macro-gallery-moth.jpg
    macro-gallery-moth.jpg
    24.3 KB · Views: 37
Last edited: