Welcome to the Viking gang!
You probably have the same breaker panel as the E-34 and E-38 of that era. Same as our boat, too.
Shore power switch 'on', main AC panel should have a breaker labeled for battery charger. Turn that on. I believe that the charger is wired directly to the battery (or both if a second bank is fitted).
With switches 'on' see if there is an 'on' light indicator on the charger. Your volt meter should show about 14 volts when being charged.
Note that if the original panel meter is badly faded or even deceased, you can get an identical new one from NewMar.
That OEM 8 to 16 volt expanded scale meter is great to have in service as a check against whatever more-sophisticated electrical system you install later.
Assemble an electrical monitoring system using these analog, panel mount meters. Meters are available with 2-1/2″ and 3-1/2″ face sizes. Easy to read graphics with unit divisions give precise readouts at a glance. Designed for front panel mounting. AC Meters AC Volt 0-150 AC Volt 0-300 AC Amp...
dcpoweronboard.com
I replaced ours when it finally died.
Shore power note: inspect *closely* the 30 amp cord and inlet fitting on your boat for any sign of corrosion or past arcing. Any singed material is cause for replacement. (You might find a new cord and inlet installed on a used boat, but many owners just ignore this for years n years.
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