MAN CRM V8-900s, Twin Disc Drives; Onan 21.5 Generator
Brian,
It should read 120V or line voltage. Below it is the ammeter which registers your load. I assume you have a 30 amp cord and 120V system/generator...
Saying it another way... The Voltmeter does not register use. It shows that you are connected to shore power correctly and have 120V coming into the panel.
The volt meter shows that you have 110 volts available to use, though yours in the pic is showing that nothing is "available" connected, the main breaker is on but still reading near zero so I am guessing that shore power is not connected at the time of that photo.