New Cheap Chinese MM and this one is bad, I think. - Page 1
Forum section: electronics / projects

author: DW1961
author_rank: Frequent Contributor
timestamp: September 26, 2020, 07:02:06 pm
content: I had a $17.00 unit I needed to review for Amazon, so today I took in a part.It's suppose to be CAT III 600V.I really wrote a horrible review on this meter. I couldn't see any MOVs, just diodes and resistors, one small PTC (I think) plus the current side uses glass fuses. The glass fuses set me off, but what really set me off is that the battery leads are not contacts, but wires soldered to the board. Just taking off the back and moving it out of the way broke the positive connection. When I got a magnifying glass, I could see the negative connection had two broken wires also, and was about to break off itself. I suspect they used CCA wire and it's really brittle. I've soldered 22AWG copper wires and abused the hell out of them and they don't break off like these did.Anyway, I just had had it at that point. I posted my images and stated in my opinion the unit's only CAT certification is screen printed on front of the unit and described the bad solder joints and glass fuses, and gave it one star.I tossed the unit into the trash because I don't trust it, but then pulled it back out again because I can re-solder the battery contact, and use it for DC low voltage stuff--maybe. I just don't trust it to even take those types of measurements.If any of you think I have over reacted, based on the images (and the fact that simply taking off the back broke the battery lead wire, let me know and I'll modify the review. Those glass fuses and broken battery leads just really set me off. I mean there is kinda shitty and then there is just pure feces.

author: E-Design
author_rank: Regular Contributor
timestamp: September 26, 2020, 07:16:22 pm
content: DW1961, this is going to be your legacy. Finding, exposing and reviewing these poorly designed MM.If you go through enough of them, maybe you can let us know when you find a good one!Dont throw them in the trash, hang them on a poster like the FBI most wanted. Make a wall of shame of sorts..

author: KMoffett
author_rank: Regular Contributor
timestamp: September 26, 2020, 08:49:49 pm
content: All that, and no make/model or Amazon link?

author: floobydust
author_rank: Super Contributor
timestamp: September 27, 2020, 02:07:08 am
content: It looks like your usual "race to the bottom" chinese multimeter, for USD$8 don't expect much.It seems strange to compete at the under $10 multimeter level. Over 660 results on Amazon searching for 'digital multimeter' under $25. Bit of a glut? Then they nickel and dime for features such as temperature or frequency measurement, why bother with another model number for that.The IEC "Cat. xxx" text/label is not legally protected and anyone can put that on a product.BM15A, SZBJ Shenzhen Binjiang Electronics Features: "Safety rating EN61010-1, CAT.III 600V"Mini fuses 3.5mmx10mm with fake UL stamp on the end caps. Nice touch. Real fuses are ceramic only (not glass) and 250V rated.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: September 27, 2020, 02:19:27 am
content: I think all of your factual comments should stay in the review. But maybe your star rating is a bit harsh. With this logic. You are not wrong, it is a terrible little piece of trash. But how does it compare with others in its price range. There are a great many terrible pieces of trash in that range. This one seems perhaps a little below average, but my experience with these things is less than yours. Is it really worst of breed?There are bound to be people out there who really can't afford a good MM. And reviews should guide them to the best of this cheap category, while pointing out all of the shortcomings of a bottom dollar unit.

author: DW1961
author_rank: Frequent Contributor
timestamp: September 27, 2020, 04:39:04 am
content: Quote from: E-Design on September 26, 2020, 07:16:22 pmLOL. Naw, my fascination with them is now over. The only units I will buy, if I need to buy one, is the Amazon brand, and then the name brands, like Fluke. Tired of wasting my time on this junk.I want to figure out my problems with LED strips now. I need to finsh building my strip so I can install my radiator and get my main rig running again.

author: DW1961
author_rank: Frequent Contributor
timestamp: September 27, 2020, 04:52:56 am
content: Quote from: KMoffett on September 26, 2020, 08:49:49 pmOh, I want to wait to see if I really over reacted before that. It's not even posted yet, but when it is, I'll link you to it.The vendor was really nice and said he tried to get the CAT certification from the manufacturer, but the manufacturer never replied. I told him what I found and was sorry he got stuck with these and not to worry about the CAT cert because there isn't even going to be one for this unit. He's a really nice guy.I've never run into mean or otherwise unhelpful Chinese sellers. They are always the most kind people to work with, and generous too. I reviewed a Bluetooth amplified bookshelf speaker that I was really impressed with, and I also reviewed their passive bookshelf speaker and was impressed with that too. However, the Amplified unit has play in the bass and treble knobs (movement back and forth, or slop). They probably will never cause any problems, but one of the things I do when reviewing anything with knobs is to check their wobble. I hate pots with wobble in them. What I mean is that you can grab them and move them back and forth a little. Not a whole lot, but more than feels right to me.They wrote me back and said they checked their other units and they all have some wobble in them, and they would offer me a 20% off on them if I wanted to keep them. They also said they were contacting the manufacturer and would see if they could improve the pots on future runs. I asked them if they would consider just sending me a pair of the passive speakers (I already have one set) and they said sure and shipped them the same day. I received them today. (They said keep both of them.)The same thing happened with a another class D amp I reviewed lately. The treble knob had some play in it, and I told the seller about it. She immediately wrote me back and said they wanted to send me another unit and to keep the one I had. (The play is not from the retaining nut. The first thing I do is take the knobs off and check that.)Anyway, the point is that the vendors are not to blame for this. They're just trying to make a living. I feell bad about telling them when there is a problem, but quality issues are what they are.

author: DW1961
author_rank: Frequent Contributor
timestamp: September 27, 2020, 04:54:44 am
content: Quote from: floobydust on September 27, 2020, 02:07:08 amI'm not a an attorney, but it seems you cold get them for false advertising because a CAT rating is something it DOESN'T have.

author: DW1961
author_rank: Frequent Contributor
timestamp: September 27, 2020, 05:02:59 am
content: Quote from: CatalinaWOW on September 27, 2020, 02:19:27 amThe power lead broke off the battery solder joint just taking the unit apart!The other one everyone helped me tear down was questionable, but it had ceramic fuses, two PTCs, on board press down contacts for the battery, etc. That's my low point. However, it was 35.00 and you can do a lot better buying an Amazon brand that is CAT certified for less.I bought my CAT III 600V Amazon brand for $13.00, currently selling for $16.00. It's made by a known brand that puts out decent meters. So, well, F those cheap ass unsafe, crap models going for more. I wouldn't guide anyone to them. I'd guide them to the Amazon brand.I feel sorry for people buying them because they make them pretty on the outside, and no one is tearing them down and reviewing them, but "Oh great meter, I love it, blah, blah, blah. If they did, and researched like I have, they'd be really disappointed.This thing was a pure piece of shit. The knob contacts were just shit. I would not be surprised if the contacts break off just turning the knob. That's why I tossed it into the trash. I don't want to take any chances with it.The other one you all helped me review, I'd probably use it for measuring low voltage DC stuff. Not this new one.