A device that measures volts.
The volt.
It depends on what you want to monitor. Most commonly the volt meter is connected in parallel with the battery or the alternator.
Volts
Parallel
Purchase, borrow, or have someone with a volt meter or multimeter check it for you. If you don't know what a volt meter or multi meter is, have an electrician check it for you.
There is no volt meter or amp meter in a DC watt meter.
Yes
as a tester
Volt-Ohm Meter
massure volt
A
Please re-phrase your question. A volt meter does not read volt amps.