Dangerous multimeter : MASTECH M890G / M890G2 (aka DC Electronics DC03) - Page 1
Forum section: electronics / testgear

author: uski
author_rank: Frequent Contributor
timestamp: February 12, 2014, 06:50:00 am
content: Hi,I was totally uneducated about multimeter safety before watching Dave's videos. Thank you Dave.Tonight I took apart my old, trusty (I thought !) multimeter I've been using for years.It's a "D.C.Electronics" model "D.C. 03"I wanted to see the protections inside and try to compare with what I've seen on the videos.Are you scared ? You should be, because after opening it I am totally scared !At first glance, nothing looks wrong, right ?Hmm, wait. "20A UNFUSED" ?1000VDC/700VAC max ?Interesting. Let's take a look inside...OK let's focus on the input circuitry...What a nice input protection... a single glass fuse, nothing else !The 20A input really is unfused.No PTC, no MOV, nothing.And on the picture above, look at the center-left, above the red wire...Look at those 2 diodes and those 2 resistors... their legs almost touch each otherThat may be or may not be a safety issue, but it's definitely a reliability and QC one !Speaking of clearances :Look at the fuse.. look at that clearance between the fuse and the resistor... or that lack of clearance !Remember from the first pic, the rightmost banana jack a few millimeters away from the lower fuse terminal is the unfused 20A input !And look at the clearance around the shunt resistor :There is like 2mm between the pot and the shunt.Wait... what's that ?MASTECH M890G2(or M890 G2 or M890G 2 - just making sure people can find this when they use Google)180194... might be a datecode ! January 18 1994...I can find it for sale today on the Internet on many websites ! I could even find it for $50+ ! Incredible !I'm afraid they sold thousands of those, and many must still be in use today (like mine !) or available as "new old stock".And MASTECH seems to be still selling multimeters !It's possible that they have improved (if the datecode is correct, this is 20years old technology), but still...The importer is clearly at fault. I don't think this piece of sh** could be legally sold; it doesn't even have the CE mark !!! (this was purchased in Europe).At least, the manufacturer wasn't lying by putting false labels and safety ratings. But still they should not have sold this because there is absolutely no way for an uneducated user to know the danger of using that piece of hardware.I used that thing a few days ago to check mains voltage...It's a shame, I liked this multimeter ! It feels solid, while still being lightweight. Battery life is huge, accuracy is OK for very basic use, and it has many features (thermocouple temperature measurement with standard socket, capacitance, ...). But safety first ! So... be careful - be safe... my advice : DON'T USE THIS ONE !So, what's your opinion on that multimeter ? Would you use it or toss it ?uski

author: retiredcaps
author_rank: Super Contributor
timestamp: February 12, 2014, 07:29:34 am
content: Thanks for the pictures. I always like seeing the insides of a meter regardless of price, brand and country of origin.It looks like it has two PTCs (circled in red). Yes, I would use this multimeter on low voltage/current enviroments.However, if I had to use this on mains or high voltage, I would get aligator clips for hands free operation. Having said that, this meter may not survive 240VAC if it is in ohms mode?

author: uski
author_rank: Frequent Contributor
timestamp: February 12, 2014, 07:43:53 am
content: Hi there !Quote from: retiredcaps on February 12, 2014, 07:29:34 amIf I remember correctly I paid around 25 euros (35 USD) for this one, it was a "closeout deal".Quote from: retiredcaps on February 12, 2014, 07:29:34 amI think you're right !Google gives me two different schematics for that multimeter.I have attached them to this post. It looks like there is at least one PTC for the ohms range.However I wouldn't trust them for 20A...(and there is no PTC for that range anyway, according to the schematics)Quote from: retiredcaps on February 12, 2014, 07:29:34 amFortunately it's the environment in which I'm using it mostly. But still, with the very low clearance and the component legs that are almost touching each other, it may be unsafe (not a death risk, but a risk to blow up the circuit you are using it on).Quote from: retiredcaps on February 12, 2014, 07:29:34 amI can't manage to read the schematics (I don't understand how they connect the points of the rotary switch) so I can't say, but if you can read it, let me know, it's an interesting discussion !From my understanding, the NPN transistor "Q4" will blow up if in ohms mode with 240VAC.I might try some day, if I get bored... I'll (safely) make a video if I do so(don't try this at home)uski

author: retiredcaps
author_rank: Super Contributor
timestamp: February 12, 2014, 07:59:42 am
content: Quote from: uski on February 12, 2014, 07:43:53 amYes, I wouldn't use it for 20A especially if it is unfused. I rarely measure current and when I do it is typically less than 1A DC. I would love to get a DC clamp for automotive work, but so far I haven't needed one.QuoteYou can carefully bend some of the components so they are not touching. Whether it stays that way after an accidental drop is another story.QuoteI'm just learning how to read schematics, but I will take a look sometime over the next couple of days. It is 1AM and I'm off to bed soon.

author: retiredcaps
author_rank: Super Contributor
timestamp: February 12, 2014, 08:10:07 am
content: Quote from: retiredcaps on February 12, 2014, 07:29:34 amI should mention that I use the above procedure regardless if I am using a Fluke 87V or $2.99 Harbor Freight multimeter.Good safe practices and procedures are my first line of defense and a good multimeter protects you from the "oops" moments.

author: deth502
author_rank: Frequent Contributor
timestamp: February 12, 2014, 09:31:16 am
content: this is why i feel most of this "safety" hype bullshit is overrated.the meter was fine for you for 20 years and you loved it. it never detonated into a nuclear explosion and killed millions of children, but yet now you feel like all of a sudden it will.dont get me wrong, a nice well designed meter with some protection is good, but if you dont fuck up and just use it correctly, it really dosent matter.

author: Jasper
author_rank: Contributor
timestamp: February 12, 2014, 10:42:46 am
content: Still, "will usually not kill you if you're careful" is not a particular recommendation for me. And, really, with meters available for not *that* much more of much higher caliber, like the Uni-T 61E or Fluke 15B or a ton of others that excel in various disciplines, well...

author: amyk
author_rank: Super Contributor
timestamp: February 12, 2014, 11:26:31 am
content: Quote from: deth502 on February 12, 2014, 09:31:16 amHow else would companies like Fluke sell their really safe meters?I definitely wouldn't use this one or the infamous 830s on the type of high-energy circuits they show in their safety videos, but for low voltage low current stuff it's not really an issue.

author: uski
author_rank: Frequent Contributor
timestamp: February 12, 2014, 01:52:27 pm
content: Hi,Quote from: deth502 on February 12, 2014, 09:31:16 amWhile some people here definitely have more experience than I do, life showed me that :- no matter how careful you are- no matter how clever you are- no matter how you try to stay away from people who might help you making a mistake...you WILL make a mistake someday.Assuming that you can avoid it is just being blind.Trust me (or not), you will make a mistake some day.I don't need a multimeter that totally survives in the event of such a mistake.It doesn't matter if it smokes, makes a big bang, or doesn't work anymore afterwards.However, what I want is a device that I know will fail safely.When looking at the design of that multimeter, I can't say it will fail safely for the operator.This is my definition of "safe".Just look at this video and try to imagine that you have the meter in your hands when this happens :I have hope that the "bullshit" "overrated" meters will behave in a more appropriate way...Using a product for 20 years without an accident does not mean an accident will not happen tomorrow. Multimeters are electrical tools and electrical tools need to be safe.I totally agree that using the meter has been mostly safe for my use, because yes I've used it on low power low current low voltage systems in the past. This is also why I won't be tossing it away, but I'm not going to connect this to AC mains anytime soon. I wanted to make people with similar multimeters aware of the risk they take if they do so.uski

author: sync
author_rank: Frequent Contributor
timestamp: February 12, 2014, 02:11:45 pm
content: Quote from: uski on February 12, 2014, 01:52:27 pmWhen you have that meter in your hand in that situation your are a moron. Very simple. That is a high energy source. This is an area for professionals with professional equipment only. I saw electricians working with face shielding and protective clothing on such circuits. A safe multimeter is not enough.

author: uski
author_rank: Frequent Contributor
timestamp: February 12, 2014, 02:16:00 pm
content: Quote from: sync on February 12, 2014, 02:11:45 pmThe main issue is education. People (like me, I agree !) are not educated about this.And I'm a hell of a lot more educated that the average Joe that fixes his light bulb.By creating this thread, I wanted to show the risks. Thank you for participatingHowever, I want to point out what you said "a safe multimeter is not enough". So, we seem to agree that you still need a safe multimeter. This is the point of this thread.Why ? Because no matter how educated you can be, if you shut off a circuit, write "DON'T TURN IT BACK ON" on the breaker, go away make your measurement, some guy might still come up and turn the breaker back on to watch the end of the Superbowl.You need "fail safe" tools.

author: sync
author_rank: Frequent Contributor
timestamp: February 12, 2014, 03:07:27 pm
content: I'm also not formally educated. I working with mains voltage since I was a kid. BUT I would never working on such a high energy circuits like in the video. These are very, very dangerous. Stay away from them!http://ecmweb.com/arc-flash/case-deadly-arc-flashRegarding fail safe tools. Yes, multimeters and other tools should be safe. A multimeter with unfused current range is bad. But even with a "safe" Fluke you can kill yourself easily. Connect the leads to current measurement, one lead to hot and touching the other lead.... Even safe tools are not foolproof. When working with dangerous things you should know what you are doing.

author: Huluvu
author_rank: Regular Contributor
timestamp: February 12, 2014, 07:18:08 pm
content: I own really a lot of Multimeters, but for Mains (Household, Electrical Cabinets ...) I would always use my trusty "Duspol"(Similar to an Fluke T130)It is a question about the right tool and for High Energy Circuits you often need to check if there is Energy or not (the exact value doesn't matter)

author: pomonabill221
author_rank: Frequent Contributor
timestamp: February 12, 2014, 09:11:49 pm
content: Maybe the diodes and resistors leads being close like that form an overvoltage spark gap? YEAH, RIGHT!

author: retiredcaps
author_rank: Super Contributor
timestamp: February 12, 2014, 10:34:39 pm
content: Quote from: uski on February 12, 2014, 07:43:53 amWell, in this recent thread, the NPN transistor was faulty when the multimeter was set to ohms mode on mains ACV.https://www.eevblog.com/forum/testgear/tillquist-dt-447-true-rms-model-187-fine-instruments-corp/In Dave's ohms overload test (eevblog #252), all the multimeters survived including the cheap Vichy VC99. However, in Martin's review of the Uni-T UT90C meter, it died on mains ACV mode when it was set to HZ. Oops.

author: AG6QR
author_rank: Frequent Contributor
timestamp: February 12, 2014, 10:49:20 pm
content: The teardown was enlightening in showing where the problems lay.However, without a teardown, I could have told you that the meter was unsafe for high energy circuits when I saw the socket for transistor hFE measurement, the capacitor socket, and the thermocouple socket.As a general rule, meters that are very safe to use on mains power won't have these extra sockets. Just try to find them on a Fluke, Agilent, Gossen, or other high end industrial meter intended for high energy circuits. (You may find them on high quality LCR meters or similar devices that are NOT intended for mains power measurement).When a meter's two primary leads are connected across different phases of mains voltage, then the chassis of the meter and virtually every piece of metal on the circuit board is likely to have mains potential on it, relative to ground. Those types of sockets that allow you to easily insert component leads will also allow fingers to get too close to mains voltage. And if a component is actually inserted in one of those sockets at the same time as the probes are both at high voltage, well...Those component sockets indicate that the designers didn't place utmost importance on safety for high energy voltage measurements. Maybe there's a meter somewhere that has those sockets but doesn't have any other problems with clearances, poor fuses, etc. If so, I haven't yet seen it.

author: deth502
author_rank: Frequent Contributor
timestamp: February 13, 2014, 12:17:17 am
content: Quote from: sync on February 12, 2014, 02:11:45 pmi think those shitty meters are great at weeding out the idiots from the gene pool. darwin at work.

author: uski
author_rank: Frequent Contributor
timestamp: February 13, 2014, 02:08:13 am
content: Quote from: AG6QR on February 12, 2014, 10:49:20 pmThank you for that very interesting remark, I never made the link between those sockets and poor safety !Quote from: deth502 on February 13, 2014, 12:17:17 amYea, and you think shitty cars are great because they kill people in terrible car accidents every day ?Seriously...

author: deth502
author_rank: Frequent Contributor
timestamp: February 13, 2014, 10:38:13 pm
content: Quote from: uski on February 13, 2014, 02:08:13 amapples and oranges, boy. apples and oranges.a failure of a faulty automotive system has nothing to do with user input. being a fucktard and putting your tongue to the 10,000v transformer secondary to see if its on, you only get what you deserve.

author: uski
author_rank: Frequent Contributor
timestamp: February 13, 2014, 10:41:09 pm
content: Quote from: deth502 on February 13, 2014, 10:38:13 pmI agree with you but none spoke about connecting such a multimeter on a 10,000v secondary.However, connecting it by mistake as an amp-meter on a mains circuit, that can happen, and it's not being a fuc**ard (is it ?), when the multimeter is rated at 750VAC and supposedly protected by a fuse.

author: LordKaos
author_rank: Newbie
timestamp: March 25, 2014, 09:59:23 pm
content: Hi!Mine started to turn on as pleasure, no matter when I wanted...now, I won't turn onAnybody is having the same trouble?Battery is ok, and the problem cames while it was in its box.Thanks Pals.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 25, 2014, 10:29:19 pm
content: Quote from: LordKaos on March 25, 2014, 09:59:23 pmHow do you know the battery is ok?Do you have another meter to measure the battery and defective meter?

author: oldway
author_rank: Super Contributor
timestamp: March 26, 2014, 08:16:20 am
content: Quote from: uski on February 12, 2014, 01:52:27 pmThat's a bullshit....If we assume that who is using a device, whatsoever it is , does not know what he's doing , we can easily show that almost everything is dangerous.Using a hair dryer, when you get out of the shower , or worse, when you are in the bath , is certainly far more dangerous than the worst multimeters can be.Working on electrical circuits with high energy , it is a job of specialists, electrician or power electronic engineer, not for amateurs or hobbyist at all.The 10A input current of the multimeter in this video is connected to and powered from a high energy source . (NH fuse with breaking capacity of 100KA )An electrician or a power electronic engineer never uses this current input of the multimeter simply because he always measures the current with a current clamp .I used anUNFUSEDFluke 73 during 5 years to measure voltages on DC bus of high power DC drives up to530V 5000A...It's not dangerous at all if you know what you do...If absurd errors are possible, we may as well show that the simple fact of having opened this cabinet is dangerous because the same idiot that connects the current inputs of his multimeter could also try to tighten the cables connections with not isolated tools and without taking all necessary precautions to ensure that these connections are not under tension and they could not be turned on accidentally.

author: LordKaos
author_rank: Newbie
timestamp: March 26, 2014, 01:00:58 pm
content: Quote from: retiredcaps on March 25, 2014, 10:29:19 pmHi!I tested three different new batteries and nothing happens. (batteries tested with another multimeter and my tonge for sure)The strange thing is that when the fail started to appear, after some turn ons and turn offs, the multimeter turn on. I also check the power switch and it´s working ok.Thanks

author: G7PSK
author_rank: Super Contributor
timestamp: March 26, 2014, 02:24:32 pm
content: Quote from: retiredcaps on February 12, 2014, 10:34:39 pmThe meter blew on HZ because Martin did not read the specifications carefully enough if he had he would have noticed that on the HZ range maximum voltage rating is less than 30 volts rms, it is intended for audio work on the HZ range if you want to read the HZ from the mains or a power circuit you should set the meter to the relevant volt range and then press the HZ button.Incorrect use whether deliberate or accidental will always get you into trouble, DMM are not really the right tool for working on high power circuits, if you look in the kit box of linesmen they have separate voltage meters and amp meters, some of them on long fibre glass poles.I always use a clamp meter for measuring the current from gen sets and an old AVO meter for voltage testing, you do not need to worry about a few milli amps or burden voltage when there is tens or hundreds of KVA in the circuits.

author: oldway
author_rank: Super Contributor
timestamp: March 26, 2014, 03:10:21 pm
content: Old AVO analog meters are very dangerous, you never should use them for measuring voltage on high energy circuit because the inputs are the same for voltage and current.All multimeters with the same inputs for voltage and current are dangerous.The circuit breaker of those old AVO meters can't interrupt high ac current nor any dc current ...It is slow acting (actueted by the pointer) and has little clearance between contacts and nothing to help extinguish the arc.I already have seen a lot of old AVO with fully damaged circuit breaker.

author: G7PSK
author_rank: Super Contributor
timestamp: March 26, 2014, 03:29:47 pm
content: I never ever switch the thing to current if I could be bothered I would disconnect the current shunts inside. The overload circuit breaker is a magnetic unit in the one I have, an ex MOD panclimatic, will survive just about any thing short of getting shot, certainly withstand a bow up from inside as it is a metal case unit with O ring seal, so heavy as well that the user will not be holding it in their hand. To my mid that makes it a very safe meter to use far safer than any Fluke with short leads that has to be held close to the work under test. And it has proved itself several times where I have connected it to 415 volts after inadvertently leaving it on 100 volt range a very undramatic click as the trip pops then just a push on the button and it's ready to go again.As I said it before it is not so much the meter but how it is used.

author: LordKaos
author_rank: Newbie
timestamp: March 26, 2014, 03:39:57 pm
content: Quote from: G7PSK on March 26, 2014, 03:29:47 pmWhy to disconnect the shunt? In another multimeter, last week I missconnect the positive point and 8A runs trought the multimeter....I was lucky that the shunt acts as a fuse (and one of the cables too)...and that current don´t damage the whole unit.I repaired the shunt with an small 5mm of solid cooper conductor...at least to be used with lower currents.

author: oldway
author_rank: Super Contributor
timestamp: March 26, 2014, 05:51:15 pm
content: Quote from: G7PSK on March 26, 2014, 03:29:47 pmYou really don't know anything about AVO and how they work.Try to connect it to 415Vac high energy with knobs selecting 10ADC...It will explode in your hands and the circuit breaker will not even trip (because it is actuated by the pointer reaching full scale) as the pointer don't move at all in this condition.And try (better not !) to measure voltage on a 300V battery of several hundreds Ah with 10AACselected...Again, the circuit breaker will not trip (for the same reason I have already explained) and your AVO will explode in yours hands...And if 10ADCis selected, the circuit breaker will trip but will for sure not be able to interrupt 300Vdc.I have 3 Universal Avometer at home, one model 7, one model 8 Mark 1, and one model 8 Mark6.In the late one, it's the printboard which act as fuse !

author: Carrington
author_rank: Super Contributor
timestamp: March 26, 2014, 06:41:48 pm
content: My first digital multimeter, still working.

author: retiredcaps
author_rank: Super Contributor
timestamp: March 26, 2014, 09:35:48 pm
content: Quote from: LordKaos on March 26, 2014, 01:00:58 pmI would check for V+, V- on the 7106.There is also a way to enable the test pin (37) to test the lcd. See the 7106 datasheet.http://www.petervis.com/meters/ICL7106%20and%20ICL7107%20Digital%20Meter/ICL7107%20LED%20Display%20Settings.html

author: Macbeth
author_rank: Super Contributor
timestamp: March 26, 2014, 10:12:54 pm
content: Quote from: G7PSK on March 26, 2014, 03:29:47 pmAhhh... That would be AVO "Test Set No.1" with the 2.5kV range if I am not mistaken. I also have one dating back to the early 70's, but the "panclimatic" compensation PCB on the back of the meter mechanism was rattling everywhere as the boltheads had came apart. Sadly my attempt at drilling them out in order to tap and replace became a cropper as all the swarf got stuck in the magnetic coil. Doh!

author: zapta
author_rank: Super Contributor
timestamp: March 27, 2014, 02:10:22 am
content: Quote from: uski on February 12, 2014, 01:52:27 pmGreat video. This DMM should on ITAR list.

author: Mr. Coffee
author_rank: Regular Contributor
timestamp: March 27, 2014, 04:17:01 am
content: I wish to explode it. Can you send it to me so I can make a video of the Mastech?

author: oldway
author_rank: Super Contributor
timestamp: March 27, 2014, 08:56:16 am
content: Quote from: zapta on March 27, 2014, 02:10:22 amStupid video and stupid idiot who make this video.If you want, you can explode every single multimeter with high energy, even a Fluke 87Try to measure 10KV on power grid with a multimeter, or 500Vdc high energy (1000 ah battery for example) on current input 10A...Fuse is not able to interrupt such a voltage and your meter will explode, watsoever the brand !In normal use, an electronician will never try to measure high energy main supply.Do the same as this video, but connecting to outlet of your home....The multimeter will not explode....the 16A circuit breaker will interrupt the current and nothing worst will happen....perhaps, your multimeterr will be damaged but you will not be injuried, nor killed.If you are such an idiot to connect your test leads on 10A for measuring a voltage, better NEVER work with voltages higher than 24VI maked such mistake with an unfused analog multimeter when I was a childeren of 8 years old, and nothing bad happened....The multimeter was damaged and fuse blowed.Measuring on high power grid is not for childeren nor for idiots.It would better to say: IF YOU DON'T KNOW WAT YOU ARE DOING, BETTER NOT TO DO ITTher are safety rules for working with electricity, you have to know and to respect them.

author: han
author_rank: Frequent Contributor
timestamp: March 27, 2014, 09:30:00 am
content: Quote from: zapta on March 27, 2014, 02:10:22 amTry search capacitor explosion.then everybody should only use 5KV nonpolar capacitor....

author: Lightages
author_rank: Unknown
timestamp: March 27, 2014, 06:19:11 pm
content: Quote from: G7PSK on March 26, 2014, 02:24:32 pmMartin did nothing wrong IMHO. I am not sure when the meter he was testing was designed, what version of CAT rating spec was in force at the time, nor if Uni-T actually did real testing and design to the CAT rating. The present CAT rating standards state that all inputs, and all modes of operation must withstand the CAT rating the meter is specified to meet. With the new rules you cannot mix and choose CAT ratings on different functions.Meter safety ratings evolved to where they are for a reason. Sure someone can do the same stupid thing for years and get away with it but that does not make the practice safe. It is for the unexpected and the random events that the CAT ratings were made to address. Proper education, procedures, and equipment all have a part in the safety of the user/worker.

author: Wytnucls
author_rank: Super Contributor
timestamp: March 27, 2014, 08:07:42 pm
content: According to the manual, on the UT-90C, the overvoltage protection on all selections, except voltage (1000V DC/750V AC), is 600V peak. The meter should have survived 220V AC on Hz.To avoid harms to you, please do not attempt to input frequency voltage being tested higher than 30V.The manual doesn't mention possible damage to the meter.The maximum amplitude of 30Vrms quoted in the specs, is probably for accuracy measurement validity.http://www.uni-trend.com/manual2/UT90C%20Eng%20Manual.pdf

author: Carrington
author_rank: Super Contributor
timestamp: March 30, 2014, 02:22:10 am
content: Genuine DMM:

author: oldway
author_rank: Super Contributor
timestamp: March 30, 2014, 05:21:19 pm
content: No joke at all, I saw an "electrician" doing this....measuring voltage on power cables by touching them with his finger and not been injured.And smiling, he said: here, that's 220V and the other wire, only 110V.What about safety rules ?

author: SeanB
author_rank: Super Contributor
timestamp: March 30, 2014, 06:02:22 pm
content: His name Clifford by any chance?

author: oldway
author_rank: Super Contributor
timestamp: March 30, 2014, 09:09:27 pm
content: Quote from: SeanB on March 30, 2014, 06:02:22 pmThe only thing I know is that he is Brazilian.

author: Porto
author_rank: Contributor
timestamp: March 31, 2014, 01:19:34 am
content: Here are some pics of my old Metex M3800 DMM I used the last 20 or so years; it served me quite well.I just bought a new one, a Voltcraft VC890 True RMS thingie which I'm yet to use regulary.The internals are similar as the OP's DMM but this one doesn't use a normal glass fuse and there is an extra250v/2A fuse as well... niiiiiice!It also have one 2A fused socket and a 20A (!!) unfused socket.It also has some resistor legs nearly touching eachother so the build quality is quite the same.On the 7th pic you can clearly see I almost fried the thing once...

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 04, 2016, 08:53:56 pm
content: This DMM is still in production, probably since 1997 or so. It is very cheap, but it has many functions, units display and four input jacks. For the price it is still better than many cheap DMMS, that have only three input jacks and no units display. This 890G DMM might be OK for young hobbyists that never work with voltage above 24V or so.Yes, it has no CAT rating.I got this DMM in 2000. It still works. But you might kill it with 50V when in ohms range. :-(http://www.uni-t.eu/pl/3436-miernik-uniwersalny-m-890-g

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 04, 2016, 09:15:31 pm
content: You can buy a cheap multmeter like this, but it has shared jack for mA and volts and no unit display

author: Macbeth
author_rank: Super Contributor
timestamp: May 04, 2016, 10:41:09 pm
content: UT-136B/C depending on if you prefer a capacitance test or temperature probe. Cost ~$12 when I bought mine.It has auto-ranging and separate amp inputs. Very cute form factor and solid too.It's little tilting bale does the job well.However I am very impressed with the coat hanger version on that profitec. I especially like the twisted on brace

author: Hydrawerk
author_rank: Super Contributor
timestamp: May 04, 2016, 10:58:10 pm
content: http://www.dx.com/p/uni-t-ut136b-2-0-lcd-digital-multimeter-red-grey-1-x-9v-128293Looks nice.But it has no manual range button.Well, today I would not buy a 890G meter. If you can, buy a Brymen fromwww.tme.eu

author: Macbeth
author_rank: Super Contributor
timestamp: May 04, 2016, 11:10:52 pm
content: Quote from: Hydrawerk on May 04, 2016, 10:58:10 pmAu contraire Rodney. Au contraire! I just happened to be using it in my car today to help figure out why my passenger door central locking stopped working, and the auto ranging was too slow to capture the 12V locking/unlocking voltages. Quick presses of the yellow select button enabled me to set it into fixed 00.00V mode and all was well. (Yes, my central locking is doing the right stuff, my door lock motor must be fried!)

author: Neilm
author_rank: Super Contributor
timestamp: May 05, 2016, 06:58:41 pm
content: Quote from: Hydrawerk on May 04, 2016, 08:53:56 pmI hope they don't claim compliance to IEC61010. I was reading the multi-meter part the other day and noted that any hand held multi-meter must be at least CATIII.

author: CJay
author_rank: Super Contributor
timestamp: May 06, 2016, 11:09:48 am
content: Quote from: uski on February 12, 2014, 02:16:00 pmPPE and lockout blades come to mind here, the 'meter is only one part of the equation, if you really can't lock out a circuit to make it safe should you even be working on it?If you absolutely have to work on live high energy circuits then yes, a 'safe' multimeter is essential but you also absolutely have to have the correct PPE and even more importantly you *MUST* have safe working practice ingrained into your brain too.I reckon most of us will have met or know electricians who have horror stories to tell and I have even seen two incidents happen, both involving idiots who thought it'd be OK to work on live, high voltage multi-phase circuits but found out they were wrong.Fortunately both survived and the worst injured was back in work after a few months, almost all of his vision returned too so he was a lucky idiot.

author: guy48065
author_rank: Newbie
timestamp: May 06, 2016, 01:01:55 pm
content: Quote from: CJay on May 06, 2016, 11:09:48 amEntered the field while still in high school in 1978, working for a company specializing in field service of DC drives. Working on live circuits was the only way to troubleshoot so...An experienced co-worker suffered an exploding meter & arc-flash burns that sent him to the hospital for skin grafts to his face & forearms. It wasn't that he didn't know what he was doing--it was the union electrician he was assigned to that connected the leads to the wrong inputs. Shit does happen.

author: CJay
author_rank: Super Contributor
timestamp: May 06, 2016, 09:35:32 pm
content: Quote from: oldway on March 30, 2014, 05:21:19 pmSeen that done by an electrician who specialised in fitting out machine shops.

author: 001
author_rank: Super Contributor
timestamp: September 14, 2018, 09:12:15 pm
content: HiWhy so panic?I still use itafter 18 years it WORKS!