MASTECH MS2108A Digital Clamp Meter Multimeter AC DC Current Volt Tester

This meter is well-made for the price, and does the job - which mainly means measuring current. If you don't need to measure current you buy an ordinary multi-meter, not a clamp meter.As is too often the case with Chinese products the manual leaves something to be desired. In particular, it advises that the meter should be calibrated once a year, but gives no clue whatsoever how that should be done. Furthermore, I have been unable to find anything on the web about it., Those geeky types who publish Youtube videos on how to make perpetual motion machines or service a flying boat have so far omitted to tackle this important topic.There ARE videos on how to calibrate simple multi-meters with just one screw to adjust, but this meter has at least 8, Consequently I have left well alone. It's accurate enough, and for the price, I am a happy

I bought this for a friend who runs a repair garage as it was the cheapest DC clamp-on meter I could find. Main application being to check for faulty glow plugs and find current paths in car wiring. It is a very well engineered rugged device and great value for money. I haven't checked the absolute accuracy but it has been consistent and reliable over the first few months of use in a garage environment. Highly recommended and much better than I expected!

Its got DC current range and the price is good. Only negative is the instructions which are in Chinese only

This is a nice handy versatile instrument, but the accuracy doesn't seem up to the specifications.On the DC current clamp readings, so far up to 14 Amps, there is typically a 0.67A offset before you start, although pressing the REL button zeroed that out. Beyond that the accuracy of the reading still seems to be out by a good few per-cent, so far as I can tell by about 3%.Similarly the DC voltage readings appeared to out by 2% to 3%.When checked against a 0.5% tolerance 1 ohm 400W resistor, there appeared to be a significant inconsistency between the DC current and voltage readings of at least 3%.I have not yet properly checked the AC readings, but it is clear that for anything other than a pure sine waveform the nominal RMS readings (seemingly a corrected rectified average) would appear to be significantly in error, although this is not unusual for such a meter. For normal AC voltage the waveform in likely to be pretty reasonable, but current waveforms are often far from being a sine-wave, so significant discrepancies are likely, compared to the true RMS reading.For what it cost, it does a half reasonable job and gives a good indication, but at this price level I had hoped for something better than it seems to provide and I am rather disappointed.In the end it is apparent this cannot reliably determine AC mains RMS current, which often substantially deviates from a Sine waveform. This was the primary reason for buying this clamp meter, to evaluate power consumption, hence it is not really of much use for my needs, so I have since bought a Mastech MS2108 True-RMS AC/DC Clamp Meter, at nearly twice the price. I hope this proves to be better, as I cannot justify going to anything more expensive and I will put this down to experience.I have also just got a MASTECH MS8229, Auto-ranging Digital Multimeter, with Sound Level, Light Meter, Temperature and Humidity Tester. I don't expect all these functions to be particularly accurate, but it is handy to have something that will give a reasonable indication and comparison for these various parameters.Further note.Following the comment about my review, to which I responded, I felt further clarification was needed.As J. Forbes says "For what it costs, this device does a very good job, and will meet the requirements of the vast majority of people. Accuracy within +/-5% is perfectly acceptable at this price level."That may be fine if it was specified as a 5% accuracy instrument, but it is specified as having and accuracy of 2% of rdg +6 digits for AC and DC current and better than 1% of rdg +2 to 4 digits for voltage, irrespective of its cost.From what I understand, "rdg" is an abbreviation for "reading" or "reading value".These specifications are not part of the information provided on Amazon, but as specified in the manual supplied with the instrument.The full specifications for the MS2108 and 2108A can be found on the Mastech website at[...]I cannot check the absolute accuracy, but it is possible to check for consistency and trends. This seemed to show the instrument does not meet the claimed accuracy, so it should not be specified as such.Also quite misleading is that there are two very similar instruments of very similar appearance with very similar designations, the MS2108A and MS2108, but which it would seem work in quite different ways when measuring AC voltage and current.The MS2108A appears to measure AC as the average of the fully rectified waveform, which is then corrected by the form factor to give the equivalent RMS reading. This conclusion was supported by comparative measurements and analysis using a good digital oscilloscope, with its analysis capabilities. This is in comparison to the MS2108, which it would seem properly calculates the true RMS reading, but costs nearly twice as much.This is not much of an issue when measuring AC with a near pure sine wave, such as the mains AC voltage, but if the waveform is significantly distorted with harmonics, such as can be found with AC mains current, then this could significantly affect its accuracy.Analysis shows that with 10% third harmonic, the resulting discrepancy between the two instruments can be nearly 4%. This has nothing to do with the precision of the instrument, but is due to differences in the measurement methods.The reason for buying this meter was to determine mains power consumption for higher power equipment, where it is not possible to use a plug-in energy monitor, or to readily disconnect equipment from the mains. Where the power factor is near unity, this can be achieved by multiplying together separate current and voltage measurements.Given a "pure" sine voltage, harmonics in the current waveform don't affect the power used, but they can affect the power determined from the current and voltage measurements. With 10% third harmonic in the current waveform, the resulting discrepancy for the true RMS meter can be up to 0.5%, while for the rectified average meter the discrepancy can be up to 3.4%, or nearly seven times as much.The resulting discrepancies from this instrument are not huge, but they don't seem to come within the claimed specification. It is a pity such limitations are not clarified in the information given, to stop misleading those looking to purchase a suitable instrument, and the resulting confusion between these two different, but seemingly very similar, models.

i bought this item because it has clamp multimeter them i was very disappointed when i tested the item clamp doesn't work or when it work give me the wrong reading dc and ac volte wrong reading the only thing that work is the ohm meter i am not a happy customer don't buy it

This is the best meter I've had. Having only had cheap ones before.I hope it will last years. Lovely.

The product is as described and works very well for basic electrical checks. ( I am a DIY person, not a professional). Good value.

Great item - works as describe3d and appears to give a decent estimate of current in a DC cicuit (not tested on AC) much easier than using a shunt resistor

Sauber verarbeitet, leichtgängige Wechsel der Messbereiche, Messstrippen aus hochwertigem Silikon-Kabel, Beleuchtung von Display und Arbeitsstelle (Messzange). Schnelle Reaktion beim Messen.Insgesamt ein guter Gesamteindruck.Warum nur 3 Sterne?Kinder die Bedienungsanleitung ist auf Chinesisch. Und das meine ich wörtlich.Zumindest eine Internationale sprich englische Bedienungsanleitung hab ich hier schon erwartet