RB-See-425 Voltmeter Range

Does anyone know what the full scale input (measurement) is for the RB-See-425 Voltmeter ?
What about the required DC Voltmeter Supply Voltage ?
The picture only shows two wires (red & black), so not sure if the measurement input is the same as the dc supply input.
I am hoping the range is at least 5VDC and that the voltmeter has 3/4 lines going to it (+V Supply, GND, and +V Signal Input).
Thanx

Hi @Marc100

The voltage Range is 2.4 to 30V.
The module is powered by the source you are measuring.