Major Tech MTD70T

[AndyD]

Well I've been looking for things to keep me occupied whilst I spend my third 2 week stretch at home in quarantine since March this year when I caught a glimpse of the last piece of test equipment I bought. There's a story behind the purchase which I'll share with you, well I've got nothing better to do for the next 8 days so here goes.

I was in the third wholesalers on that particular afternoon looking for a pair of silicone test leads to replace the worn ones on my Kyoritsu clamp meter, it was the third time I'd struck out. I had no idea that three national wholesalers wouldn't have stock of something so basic. I was done driving around in hope and requested they please order the damn things, I also gave them fair warning I wanted decent silicone CATIII leads, not the no-name crap they usually peddled. They quoted R1800.00 for a pair of genuine Fluke leads which was way overpriced, even the salesman thought it was a computer error and I was just about to leave when he said 'Jesus, you can buy three complete RMS clamp meters for that price'. I told him that I doubted you'll find a true RMS clamp tester that cheap but sure enough, he disappeared into the retail section and came back clutching a box. Less than a minute on his computer he said the words I'll never forget.... 'four fifty'. After catching my breath I asked him if that was the time or the price, 'the price' he replied 'including VAT' as he pushed it across the counter towards me already knowing deep inside himself it was as good as sold. I politely enquired how the f@%k could anyone be selling a CATIII 600v 600Amp true RMS clamp tester for under five hundred bucks but alas, he didn't immediately have a definative answer to hand.

Needless to say I bought it.....yeah, yeah I know what you're thinking but c'mon, for the love of all things holy, it would have been rude not to at that price.

[AndyD]

And here it is in all it's glory;



It comes with test leads, instructions and a soft case. According to the instructions it's also supposed to come with a temperature probe as well but, even after digging the box out of the bin and double checking, there wasn't one incluced. This isn't particularly surprising because the tester has no temperature range so I'd guess the same instructions are used for another model with extra features but that didn't stop me feeling disappointed like I'd been robbed.

[AndyD]

First impressions were fairly good. It feels solid and the clamp has a good strong action to it. It came with two AAA batteries of dubious brand name but It worked fine out of the box. The leads are obviously PVC but they don't feel too bad and I've certainly seen worse with other cheap testers. The pouch is pretty good, it's lined, it's padded, the zip feels okay and the outer material is strong.

As a general overview the tester's features and ranges, it's got continuity resistance range which toggles via the 'select' button to bleeping mode and diode mode. The continuity range scale autoranges between 200Ω, 2kΩ, 20kΩ, 200kΩ, 2MΩ and 20MΩ depending on the resistance under test. There's a volts DC function and a volts AC function that both autorange between 200mV, 2V, 20V, 200V and 600V scales. There's an AC true RMS function that autoranges between 2A, 20A, 200A, and 600A. There's a NCV function which stands for Non Contact Voltage where the tester basically behaves like a voltstick, it bleeps and gives an LED visual indication when it's in proximity of a live circuit. Finally there's a function that's just got a picture of a battery so I'll call it the battery function. What does it do?...don't know, it's not mentioned in the instructions. All I can tell you is it says DC 0.00V on the screen when you select it. How is it different to the manually selected 2V range on the DC Volts function?....don't know, it's not mentioned in the instructions.

All the measurement functions can be used locked in manual ranges also.

There are 3 LED's built in to this tester, one for the screen backlight, one for NCV indication and one that works in tandem with the screen light that's a flashlight to illuminte in front of the clamp.

There's also a 'Hold' key and a 'Max/Min' key, how does it work and what exactly does it do?....don't know because it's not mentioned in the instructions.

Finally the instructions... I already had a hatred for the instructions when they promised me a temperature sensor that I didn't get. Then there's the glaring omission of some of the functions and features. They are however written in decent English.

[Dave A]

Somehow the image attachment went AWOL. Here is a link to Major Tech's product page for the MTD70T instead.

Finally the instructions... I already had a hatred for the instructions when they promised me a temperature sensor that I didn't get. Then there's the glaring omission of some of the functions and features. They are however written in decent English.

One of the reasons I love reading Andy's equipment reviews

[ians]

Andy if you looking for a fluke clamp meter ... I have a T5-1000 for sale (asking R2500 ... but would let it go for a little less ... been used a couple of times)... I want to get a fluke 117... a nice nice small compact tester ... i am over the big 189 ... 289 ...177 ... 179 ... sold all of them.

Looking at the price of the 117 ... I am thinking how bad could a small uni-T if you compare R6000 (fluke) to R600 (uni-T) ... i am all for fluke quality ... but R5000 better quality ... mmm ...need to think about it.

[AndyD]

Thanks Dave, not sure where the attached pic disappeared to but I reattached it now.

Hi Ian, the T5 is a great tester but it's not really suitable for the types of panels I work on. It's ideal for domestic and light commercial applications but I need a clamp meter that can work with higher current ranges.

The Fluke 117 is a very versatile tester, I use a Fluke 87V which I've had for donkeys years but they're a bit pricey nowadays. I also have a very basic Fluke 15B+ which I use for benchwork and board repair, it's adequate for what I need, it spends most of it's days in DCV and diode range. The only issue I see with the 117 is it doesn't appear to have a 'REL' function where you can zero out the resistance of the leads to make more accurate low resistance tests.

[ians]

I carry a model 2417 leakage current tester ... 200 mA ... 2000 mA ... 20 A ... 200 A and 500 A in my test kit ... best alround current clamp and handy for testing leakage "currents" when touching neutral to earth

I bought the T5-1000 for my tool bag ... but it didnt work out the way i was hoping.

[AndyD]

Okay, back to the MTD70T first impressions.

The leads were a good firm fit and after setting it to ohms function the display sprung to life. I was initially impressed by the large clear digits and I marvelled at how easy it was to read.


The display has a backlight which also gave impressive results;

[AndyD]

Unfortunately my excitement was short lived, when I moved the tester around I noticed that viewing it with the display tilted even slightly downwards the thing became completely unreadable. This is very disappointing with a clamp meter that's likely going to be viewed from this angle most of the time it's in use.



Yeah, I'm not exagerating when I say completely unreadable...

[Justloadit]

Hi Andy,

Check here Fluke Leads ex stock at a reasonable price

[AndyD]

Okay so with no more ado lets void the warranty and see what it has to offer.

The case is a typical clamshell type with 4 screws holding it together. This particular specimen had only 3 screws holding anything, one of them was completely stripped. The screws are self tapping and the posts they screw into have no threaded insert, this is a typical issue with cheap testers.

Separating the clamshell case revealed a very nice deep overlapping flange all the way around the bottom of the case. The overlap is 7 or 8 mm which is important because if anything goes wrong whilst the tester is in use this overlapping flange will contain any arc flash and ensure that your fingerprints remain on your fingers. The only problem here is that they made a relatively large hole for the lanyard to go into which kinda defeats the object entirely.

It appears to be plain PVC, if you cut it there's no signs of any fibreglass reinforcing mixed in with it and there's no recycling number or plastic ID numbers. It's also a one-time moulding, there's no rubberised overmouldings on the corners or anywhere else.

[AndyD]

It's a single PCB, single chip design. The sockets for the leads are made from pieces of bent steel soldered direct onto the board.

There's a sounder, 3 LED's, a few resistors, a few caps and a single PTC device, there's really not much else to it.....which is where the problems start.



On the input side there's no HRC fuses, no MOV surge protection, no diode bridge and no separation slots in the PCB. The four 2.5meg resistors that give 10meg input impedance are very small SMD devices which will discintigrate in a cloud of smoke if there's ever a transient voltage. The only safety protection offered is a poorly soldered PTC which might work for normal overvoltage but it's far too slow to to give protection in the case of transients. Also there's no flashguard panels moulded into the case around the input components. Finally, I didn't have the patience to get my vernier out of my workshop but I have grave doubts about the separation distance between the two solder terminals on the battery compartment and the pieces of bent steel they pass off as sockets for the leads when the two halves of the case are assembled.



On close inspection the track on the PCB between the red lead socket and the first 2504 resistor is thinner than the other tracks in the input area. It's not indicated as such but I wondered if it was designed for this track to blow open circuit if there was ever a transient event. Either way I think their CATIII 600V rating is highly questionable, I wouldn't recommend using this tester beyond a recommended CATII application on lower current rated final circuits and on appliances. I wouldn't personally use it for anything beyond DIY use. Never in a million years would I use it on a 3-phase DB and I'd be wearing my electrical PPE gloves that cost 5 or 6 times the price of this tester if I was using it on a single phase DB.

[AndyD]

I was originally intending to do a more in depth review including setting up a square wave supply and checking out its true RMS capabilities but to be honest depression set in and I kinda lost interest after seeing the input circuitry or lack thereof because regardless of how accurate or capable it is with testing it's still useless as a piece of equipment for any professional sparky because of it's lack of protection for the user.

Here's a picture of the top side of the clamshell case with a better view of the stripped screw holes and the garbage selactor switch contacts.



And here's a picture of the back side of the PCB.

[AndyD]

Having lost interest in the tester I turned my attention to the leads. Ever the optimist I saw a glimmer of hope...a distant silver lining nogal that I might still end up with a nice zip pouch and a halfway decent set of test leads and a couple of usable AA batteries in return for my 450 hard earned Rands.

Plugging the leads into the tester and shorting them out whilst selecting the continuity function gave a fluctuating reading of 0.4 - 0.5 ohms. Alas this wasn't what I was hoping for. I tested the resistance of the red lead using a Fluke multimeter and it was 0.27 ohms and the black lead measured 0.24 ohms. For leads that are supposedly rated at 10Amps I'd expect to see maybe 0.1 ohms per lead maximum.

Cutting the red lead revealed the issue which was just good old fashioned lack of copper and after fully dissecting the rest of it I could see that the solder joint onto the top of the probe was also a bit dry.