Steve,

On coaches of the vintage of Viv's coach a single gear driven alternator was mounted on the front (actually the rear) of the engine over the bell housing. It supplied power to the house batteries via the equalizers. Generally there were two equalizers of 50 amp capacity at the time. Instead of a single 100 amp isolator that is common on coaches today. The house battery circuit was isolated from the alternator or chassis batteries via a large relay that had the circuit normally open, but would close upon power output from the alternator.

Some converters added more battery equalizers than those supplied by Prevost.