DIN-rail voltage, current, and power meter. A powerful little unit.

There have already been several reviews here of the popular wattmeter, and I needed one too.
But given the nature of my work, I decided to get one that would leave me room to grow, so to speak.
After the jump, you’ll find photos of the outside and inside, along with a few measurements.

I’d been thinking for a long time about getting a power meter for my workshop. I even considered building one myself, but in the end I found a ready-made unit I liked.
There were three things about this meter that appealed to me most and set it apart from the wattmeter everyone knows:
LED display
Current measurement up to 100 A
DIN rail mounting.


The package contains just the meter itself and the manual—nothing else.


The manual has more information, but it’s all in English.
The specifications are easy enough to pick out, though:
Measurement accuracy: 1% ± 2 counts
Voltage and current display: 4-digit, 0.31-inch display
Active power, apparent power, and power factor display: 5-digit, 0.31-inch display.
Below 10 A, the minimum display resolution is 0.01 A; above 10 A, it’s 0.1 A.
Active power: 0–30000 W
Apparent power: 0–30000 VA
Power factor: 0.000–1.000
Measurement rate: 2 times per second.
Dimensions: 54 × 80 × 64 mm


The device is designed to mount on a standard DIN rail.
It’s 3 modules wide, or 54 mm.


The device looks very neat. If it had an ABB or Legrand logo on it, I’d believe it. No burrs, flash, gaps, or anything like that.
There are provisions at the top for connecting an external sensor (the meter comes in two versions). Mine has a built-in current transformer, so these openings are covered.


There’s a latch on the back to secure the module to the DIN rail.


And here is the device itself.
The top two displays show voltage and current.
The bottom display can be switched to show active power, apparent power, or power factor. The button is in the lower-left corner.
Three LEDs in the lower-right corner indicate which value is currently displayed.
When powered on, the meter always starts by displaying active power.


The wiring diagram is on the right side of the case.
Everything is concise and perfectly clear.


Let's take a look inside the meter

First, I checked the accuracy of the input voltage measurement.
The result was quite pleasing.
Since the meter's display has higher resolution than my multimeter's (3000 vs. 1999), you can see in the photos that when the reading is above 0.5, the multimeter displays one count higher, while below 0.5 it shows the current value—in other words, it rounds up.





Summary.
Pros
High-quality construction.
I couldn't test the meter at high currents, but it passed the tests I did perform; the results are above.
Convenient design and sufficient functionality for a meter like this.
Easy-to-read display (one of the reasons I chose this model).
Wide current measurement range.

Cons
No fuse in the meter's power supply circuit.
For better measurement accuracy, the wire being measured should be positioned in the center of the opening.

My opinion: I'm completely satisfied with the meter. I'll add a fuse later; I don't see that as a big problem. I showed above how to position the wire in the center. It's a shame I couldn't test it at higher currents, at least 40–50 A. But so far, the readings are well within the manufacturer's stated margin of error. The display is good (I wasn't too keen on the meters with LCDs).
Oh, I almost forgot: I didn't notice the meter heating up during measurement or use.

The meter was provided for review and testing by the eachbuyer store.

I hope this review was useful. I think some people will find a meter like this handy.