Arc's Lab

Second multimeter that faced the DMMCheck Plus is the UT60E from UNI-T. It’s a 4000 count TrueRMS meter with much lower specifications than the UT71C tested previously. Let’s see if cheaper is really worse…or not.

As before, DMMCheck Plus with its specification sheet if anyone is interested:

Both the DMMCheck and UT60E were left alone for around 30 minutes to get to know each other and for their references to stabilize (room temperature was 21C/70F).

AC/DC voltage measurement: passed!

AC/DC current measurement: passed!

Frequency and duty cycle measurement: passed!

Resistance measurement: passed!

I have to say that I’m pleasantly surprised with the results. Both current and resistance measurements were spot on which is incredible considering the UT60E’s specifications. Definately a permanent multimeter on my bench!

I borrowed a DMMCheck Plus from my colleague today and decided to check the accuracy of my multimeters. First up is the UT71C multimeter from UNI-T. It’s a 40000 count TrueRMS meter with decent specifications. Let’s see if it passed with flying colours or failed miserably!

Here is the actual DMMCheck Plus with its specification sheet if anyone is interested:

And now let’s take a look at the results. Both the DMMCheck and UT71C were left alone for around 30 minutes to get to know each other and for their references to stabilize (room temperature was 21C/70F). UT71C is around 4 years old, with factory calibration.

AC/DC voltage measurement: passed!

AC/DC current measurement: passed!

Frequency and duty cycle measurement: passed!

Resistance measurement: passed!

And there you have it, not bad at all considering the price! I do have to mention that the current measurement was fluctuating a bit with the backlight on (it’s probably a good idea to replace the battery).

UPDATE: I stand corrected on the previously “failed” AC current measurement. According to the manual (which I haven’t fully read), AC current accuracy is lower than what’s indicated on the UNI-T’s web site and only valid within 10-100% of the range. I tried to measure 1mA on a 40mA range and that is lower than the 10% of the range to meet the specified accuracy. Big thanks to Wytnucls at EEVBlog Forums for pointing this out!

I was looking for a decent handheld oscilloscope/meter and eventually ended up buying the UT81B from Uni-Trend. There isn’t much information available about this model so I decided to do a small review of it.

Let’s start with some basic specifications from the manufacturer:

• 8MHz bandwidth
• 40MS/s sample rate
• adjustable trigger (level and slope) with single-shot mode
• voltage, current, resistance, capacitance and frequency measurement
• 10 screen memory
• 160×160 monochrome display with backlight
• USB connection

Specs seem quite good for a handheld device and it should accurately display signals up to 4MHz. Time to check it out!

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