An ammeter with a 0.56-inch display—or, more simply, a number-watcher.

I’d been wanting to pick up a small ammeter and voltmeter, in a form factor suitable for mounting in a panel or plastic enclosure. I chose them, ordered, paid, and received them—in other words, nothing unusual so far. Now it’s time to take a closer look at what arrived. First, the ammeter.

At first, I wanted to buy a 2-in-1 ammeter and voltmeter, but I didn’t like the size of the digits. My eyesight isn’t great, and I specifically didn’t want an LCD, since an LED display is easy to see even out of the corner of your eye.
In the end, I chose one with a 0.56-inch LED display.
I ordered 2; the price in the listing title is for 1, and there was a discount when I bought them.

The ammeters arrived with my other orders in a cardboard box, packed in a small resealable plastic bag. There were no other boxes or bits of paper.
In short, pure minimalism.
Though why would our kind need instructions? We only remember them when it’s already too late—“Boss, it’s all gone wrong.” :)


This is what they look like when switched off.


Mounting dimensions: 45 × 26 mm; outer dimensions: 48 × 29 mm; overall depth: 20 mm.

The ammeters already have a current-measuring shunt.


Specifications claimed by the seller:
Current measurement range: 0–10 A
Supply voltage: 4.5–28 V.
Accuracy: 1% + 1 digit.

I measured the current drawn by the ammeter itself. With a reading of 0.00, it draws 19 mA over a supply voltage range of 5–15 V.

The current and voltage ranges were clear enough, but I was very interested in the measurement accuracy.

After testing the first ammeter, I was feeling pretty gloomy.

And the second one finished me off completely.

I was very disappointed. I had specific plans for them, but in the end things turned out rather badly.
I can already hear the question about adjustment.
Yes, I tried adjusting them. What you see in the photos is the best result I was able to achieve.

So, to sum up.
Pros —
A good, very high-contrast display (the readings are very easy to read).
Very neatly assembled.

Cons.
Just one, but it's a huge one: this isn't a measuring instrument, it's just a needle mover (at least the first one).

I suppose I was simply unlucky. I'll have to either try to repair the second ammeter or turn it into something else.
If anyone can tell me whether this is a common fault and an easy fix, I'd be very grateful.

Thanks to everyone who read my review.