friends, when designing, developing and implementing a variety of schemes for chargers or power supplies, they constantly encounter an important factor - visual control of the output voltage and current consumption. Here, Aliexpress very often lends a helping hand, promptly supplying Chinese digital measuring instruments. In particular: a digital ampervoltmeter - the device is very simple, affordable and displays completely accurate information data.
But for beginners, commissioning (connecting an ampervoltmeter to the circuit) can be a problem, because the measuring device does not come with documentation and not everyone can easily connect wires marked in color.
The image of one of the most popular among the masters of the multimeter is laid out below,
This is a 100 volt / 10 ampere voltmeter; it comes with a built-in shunt. Many radio amateurs often acquire such measuring instruments for their homemade. The digital device can be powered as from separate sources,
and from one operated and measured voltage source. But here a small nuance is hidden, it is necessary to observe the condition - the voltage of the used power source was in the range of 4.5-30 V.
masters who still do not quite understand: we connect the thick wiring in black to the negative of the power supply, the thick wiring in red - to the plus of the power supply (the voltmeter scale will light up),
we connect the thick blue wiring to the load, the second end of the load comes to the plus of the power supply (the ammeter scale will light up).
Cost: ~ 186