USS Holland Switchboard

Computer Model of Switchboard

The computer model of the USS Holland switchboard is based on a description of the switchboard in the Type 7 operating manual:

A – Voltmeter

B – 7 Point Voltmeter Switch used to connect the voltmeter to any one of seven circuits.

C – Large Double Pole Single Throw switch for the forward battery

D – Large Double Pole Single Throw switch for the after battery

E – Forward battery ammeter

F – After battery ammeter

G – Fuses

H – D.P.S.T. switch for lighting circuit

I – D.P.S.T. switch for engine room ventilating fan

J – Four lamps serve as ground detection devices

K - Seven S.P.S.T. motor starting switches

L - D.P.D.T. for reversing the armature circuit

M - forward connects the forward and after battery in parallel,
aft connects the forward and after battery in series

N - D.P.D.B.S.T. switch for dynamo field circuit

P - lamp used to break the electric arc that follows opening of the switch

R - S.P.S.T. switch for the forward engine ignitor plug

S - S.P.S.T. switch for the after engine ignitor plug