Meter (how can i wire it)

I cannot find any other place selling that exact unit, and the place you link to gives no detail at all.

As an educated guess:
Most likely, the red and black are the power supply.
If you have a multimeter, see if there is continuity between black and green, or another wire?

Green may be input common (connected to black) and one of the others the voltage input?

It also has an input to allow connection with a current shunt, for the ammeter display. (That at least is mentioned in the listing). It cannot "read" current without the separate shunt.

You could try briefly connecting the red & black to a 9V battery, to see if it powers up?
Make sure the polarity is correct. And if you try that, it is at your own risk; I am only guessing!!

I suspect it's likely similar to the diagram on page four of this, but not the same wire colours..

I would return the item to the vendor stating the reason that no connection instructions provided nor published in their site; and buy somewhere else. Vendor probably inherited the nasty chinese habit of not spending $0.0001 in a piece of paper, but multiplied the sales price by 10.

----> https://www.aliexpress.us/item/3256...vid=202303040706154911455214893570015959935_5

hobbyguy said:

how do i wire this Voltage meter?

Click to expand...

That's an ammeter.
Did you want a voltmeter?

crutschow said:

That's an ammeter.

Click to expand...

It is a combined, switchable, voltmeter and ammeter. The button on the bezel (presumably) switches between the two displays.