Teardown - Chinese Ultrasonic Cleaner 10 Liter

[orion242]

So a quick tear down of this guy.

http://www.ebay.com/itm/291236823191?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

First impressions were not bad.  Seems like a decent buy for the money.  The manual and front panel has all the hallmarks of something straight from china.

The manual seems pretty adamant about not running the unit for long periods at a time or risk failure.  Always something that instills confidence.  For my purposes, this is not much of a problem.  The unit has a sizable cooling fan…so wonder what they are driving to the max or further?

Inside the beast things look fairly nice.  Most all the wiring is tied up nice and in heat shrink tubing.

First thing I found a bit "dicky" as Dave would call it is the case ground.  They connected it with a ring terminal to a screw and nut holding the handle together.  No lock tight, no lock nut or washer.  Nut comes loose, there goes the ground.  Easy enough to fix.

[orion242]

Looking at the driver boards, they seem to be clean.  They spent the time to fuse them at least.  The main transistor driving the transducers is a FJP13009 with a decent heat sink.

Going after the processor board was like entering a house of horrors.  What dark hole did this turd come out of?  Dirty as hell and crusty component placement.   Sure seems like the driver boards didn’t get made in the same place.

After blowing off it became apparent what all the crap was on the board.  Apparently the cheapest tack switch in the market that day was too long.  No problem, just file them down after manufacture.  Guess plastic isn’t conductive so why clean off the board.

[orion242]

All in all I'm happy with it for the money spent so far.

Quick check of the power draw and it lines up with the claims.  Heater is ~230W and the ultrasonic is ~240W.

The heater is a bit under powered IMO.  I may add some insulation around the tank edges internally to see if that helps things a bit.  It seems to maintain 60C once it finally makes it up there.  Starting with hot water is a must unless you have all the time in the world.

[miguelvp]

Nice, I did look at them a while back but I can't justify the price just yet. Maybe I'll tell the wife that it's for her wedding ring and other things that need to be clean/sterilized.

Thanks for the teardown.

[saturation]

Nice find.  I does seem decently made, with some flaws as you point out.  I'm in need of one.  There is a more popular version [ 290 sold] with only 2L basin for $75.  A problem I find with these  cleaners is non-industrial quality tend to have US transducer failures after a while.

Was the temperature setting accurate?  Was the timer accurate?

[orion242]

I checked the temp a few times and it's withing 1-2C of the setting, which seeing temp sensor is just foil taped to the bottom of the tank is about all I would expect.  I didn't bother with the timer, but seems reasonably close.

I assume the transducers are the first thing to go also.  Ebay has an assortment of these transducers, I'm sure a replacement can be found there.

http://www.ebay.com/itm/50W-40KHz-Ultrasonic-Piezoelectric-Transducer-Cleaner-for-Cleaning-Medical-/161418870003?pt=LH_DefaultDomain_0&hash=item2595507cf3

The transducers are epoxied onto the tank, so removal and replacement might be a treat, but they are cheap enough source.

[orion242]

Not high on my "to-do" list, but just thinking about it, I bet it wouldn't take much to hack into the drivers to externally fire them for sweep frequency.  There are only 4 wires between the processor and driver boards.  2 must be power for the processor, the other two have to be signals for kicking on the heater and transducers.  Driver boards don't have much to them as you can see.  Add a micro and vary all 4 transducers 2-3Khz around 40hz when the processor kicks them on.

Project for a rainy day perhaps.

[saturation]

Thanks orion242.  Yes, my concern for the controls is that if the unit is dodgy it may shut off too early or too late and if it fails to shut off it will prematurely wear the US transducer.  Also, better to burst 4 minutes x 5 than sustained at 20 minutes so I'd like the timer to be ~1 min accurate. 

I too load the unit with hot to warm solution to speed up cleaning.  But I'd like to know the unit keeps the solution at some temperature consistently so I need not reheat it and if at least consistent I can add or subtract an offset as a correction factor. 

I checked the temp a few times and it's withing 1-2C of the setting, which seeing temp sensor is just foil taped to the bottom of the tank is about all I would expect.  I didn't bother with the timer, but seems reasonably close.

I assume the transducers are the first thing to go also.  Ebay has an assortment of these transducers, I'm sure a replacement can be found there.

http://www.ebay.com/itm/50W-40KHz-Ultrasonic-Piezoelectric-Transducer-Cleaner-for-Cleaning-Medical-/161418870003?pt=LH_DefaultDomain_0&hash=item2595507cf3

The transducers are epoxied onto the tank, so removal and replacement might be a treat, but they are cheap enough source.

[BillWojo]

Years ago I had a customer ask me to look at a large Bronson? cleaner. I was surprised to see that the transducers where just epoxied to the bottom of the tank. 4 of them were just hanging off by there wires. Seems like the epoxie just gave up. The control circuits were off to the side so they didn't land on them and short anything out. I assume that this stuff is built better than that? It's probably at least 25 years old at this point.

BillWojo

[SeanB]

Normally you dismantle the transducer and silver solder the base to the case, then put it back together with the correct torque when cool. Epoxy is both faster and you do not run the risk of disturbing or breaking the ceramic. Unless both surfaces are totally clean ( chemically clean so they are reactive) and have the right surface roughness for mechanical surface area, and the epoxy is mixed thoroughly and applied in a way that does not leave air bubbles they will eventually fall off.

[SL4P]

Sorry for being pedantic - but it's a TACT switch,
as in TACTile.
Cheers

[orion242]

Well after firing a handful of batches through it I noticed an issue with it.

The temp sensor is taped to the bottom of the bin.  On 2 sides, about 1" up from the bottom, the heaters are taped to the bin.  If you leave the heater on to take the bath up to temp, it will overshoot by 8-10C once you either stir up the fluid or kick on the ultrasonic.

Not a big issue.  I'm sure the heaters are causing convection along the sides such that the water is rising up past the heaters.  Cooler fluid is sinking down the center of the bin and passing by the sensor at the bottom.

Not a big deal, just kick on the ultrasonic for  1-2 minutes prior to use or mix the tank manually.  As long as the fluid is mixing, it does hold temp well.  Moving the temp senor may even correct this issue.

[svicar]

Helo all
does somebody know what is the transformer on both boards (that small one with blue tape). It has no data on it

best regards

[Cyberdragon]

Woah, wait a minute, is that the AC filter choke at the bottom  of the driver board? Did you do that or is that...PEELING?! That tape on that does not look good.

[lllars]

Thanks for the teardown!  It was helpful to me when researching them a couple months ago.  I ended up getting the same model, and have been pretty pleased with it.  I've used it a lot, putting maybe 50 hrs on it so far.  It seems like the ultrasonic action has actually gotten a little stronger over time.  But, it's not perfect.  I wash a lot of small metal parts, and usually some don't get all the way clean.

So, I decided to try to soup-up the cleaner.  I ordered 4 more transducers and 2 driver boards off ebay, and finally go them all installed and wired up today.  I can't really say if it works any better or not yet, because the new driver boards are overheating.  So I was only able to test it for about one minute.  I'm not too surprised. The new driver boards are only rated to 100W max, and I've got each one wired to 2 60W transducers.  It's the transistors that are overheating.  The original drivers use 13009 transistors rated to 12A, whereas the new boards have 13007 transistors rated to 8A each.  So now I've got some 13009's on order to replace them, and hopefully that will solve the problem.

In the meantime, here are some photos of my modifications.  Note that my cleaner had the heaters mounted in the bottom center of the pan, so I had to move them to mount the new transducers.

[xrunner]

I have one just like it only a smaller version (tank). Same front panel. Funny thing is if you use it for a while cleaning things, the temp of the water gets up to something like 42C. Nothing really wrong with that temp but it kinda makes it pointless to have a water temperature setting that you can set for lower temps when it will simply heat the water up anyway (by virtue of it operating) to 42C. Yea if you want it higher than that, the temp control will help you ... 

[orion242]

Thanks for the teardown!  It was helpful to me when researching them a couple months ago.  I ended up getting the same model, and have been pretty pleased with it.  I've used it a lot, putting maybe 50 hrs on it so far.  It seems like the ultrasonic action has actually gotten a little stronger over time.  But, it's not perfect.  I wash a lot of small metal parts, and usually some don't get all the way clean.

So, I decided to try to soup-up the cleaner.  I ordered 4 more transducers and 2 driver boards off ebay, and finally go them all installed and wired up today.  I can't really say if it works any better or not yet, because the new driver boards are overheating.  So I was only able to test it for about one minute.  I'm not too surprised. The new driver boards are only rated to 100W max, and I've got each one wired to 2 60W transducers.  It's the transistors that are overheating.  The original drivers use 13009 transistors rated to 12A, whereas the new boards have 13007 transistors rated to 8A each.  So now I've got some 13009's on order to replace them, and hopefully that will solve the problem.

In the meantime, here are some photos of my modifications.  Note that my cleaner had the heaters mounted in the bottom center of the pan, so I had to move them to mount the new transducers.

Wow!  Seems like overkill, but I guess if 4 transducers are good....8 must be better!

Mine is still working great, no problems with it.  Let us know how the supercharger works out.

[Restorasonics]

Yeah these little ultrasonic cleaners are great for small items

[url]https://www.restorasonics.com/medical-ultrasonic-cleaners]https://www.restorasonics.com/medical-ultrasonic-cleaners]
[url]https://www.restorasonics.com/medical-ultrasonic-cleaners[/url]

Moderator note: User banned

[MacMeter]

Yeah these little ultrasonic cleaners are great for small items

[url]https://www.restorasonics.com/medical-ultrasonic-cleaners]https://www.restorasonics.com/medical-ultrasonic-cleaners]
[url]https://www.restorasonics.com/medical-ultrasonic-cleaners[/url]

Looked at your website link. Many of those models look exactly like the Chinese rebranded ones you can find on both EBay and Amazon for half those prices?

My short story:
A year a go, I went through the research phase of buying an ultrasonic cleaner. I didn't think I'd have to go through it, but my first unit, a "buyers" highly rated $80.00 plastic Chinese model from Amazon was NG. As most know, you NEVER run these with no water in them, as you will ruin the transducer. It worked ok the first few times I used it. This model had a small heater, which you could turn ON/OFF manually. With the unit OFF, and heater OFF, I plugged it in. This time there was no water in it, but remember, it was OFF. In a few minutes, I could smell the familiar scent of electronics slowly burning. I touched the bottom of the unit, OUCH, and the heater was ON, all by itself. I contacted the seller just to confirm this should not happen, and it was agreed it was faulty and I returned it. Since I am paranoid about burning my place down, I decided to do my homework, and see if I could find higher quality units at a decent price, of course adjusting my budget upwards!

I even found a long YouTube video by Lewis Rossman. He had a higher end model and reviewed it, over a cheaper one. At first I was surprised at all the very similar units I was seeing online, eBay, Amazon, etc. They sure looked good, but the really low prices made me suspicious. I then started seeing the same electronic interface on many other sites, same units, just rebranded, some using the term "medical", with double the price tag.

As we know, just like DMM's, the printing on many Chinese products may in fact be bogus, important things like true UL listings etc. So I wanted to avoid these, regardless of their low prices, industrial looks, and wattage settings etc. Looking at the real, name brand medical units, you end up finding two popular brands and in the 2.5 liter size, I was looking at over $600, a lot more then my first $80 plastic one. I'm sure some of the price markup, was these high end name brand models are used mostly in the medical community.

I didn't want to spend that much, but I was only finding the two extremes, tons of similar inexpensive  Chinese knockoffs, or really expensive high end reputable brands, not made in China. I finally found a US company that makes them in the US, and I called and spoke with them. They have experience making even very large units for industry needs, and the prices were very reasonable. The model I bought is linked below, a year a go, it was $250, now it's $100 more, not as great a deal, no idea why the price went up so much. Regardless, they use industrial transducers, the heart of these devices. With its 60 minute timer, I've run it for hours, back to back, with heater on, works great, and I have more faith that it won't burn my home down! That alone was worth paying more for.

So beware, while many of these start to all look the same, not all ultrasonic cleaners are made the same, and some may actually be a hazard. Happy shopping!

http://www.sharpertek.com/shheuljecl6x.html

[orion242]

Another forum member asked about the fuses.

There are 3 fuses on this model.  All are 250v 3A.

[Neo2199]

Well after consideration of my budget I will try this Chinese one for $115 6L tank. The Sharpertek one is like 3 times more expensive now so out of my budget. I intent to use not that often so transducer life should be good enough for me.

[phantom]

hi! please help me! i've a similar ultrasonic cleaner! broken!!! i would like to fix it...my model is ps-40a (10lt)

this is the logic board



my problem is that i should change the chip in the circle but there is nothing written on it

[Ultrapurple]

After reading this thread I had a quick look across eBay and found a kit eBay auction: #322081244848 consisting of a driver and transducer. Although it doesn't specifically say it's medical-rated, the details on the listing include:

"6. Vibration head or transducer ceramic glue application head shock stick firmly to the pelvic floor cleaning"

Obviously a multi-purpose device!