9-3.2 Emergency Electrical System. The emergency electrical system provides a limited amount of 120 Vac and 24
Vdc power for selected essential lighting and power requirements.
This system's central unit is a battery bank on the deckhouse top that is maintained at full charge by a battery charger in
the workshop. The charger receives its power from the normal electrical system.
When normal power is disrupted, the battery bank provides 24 Vdc to an inverter. The inverter converts this power to
120 Vac, which is supplied to the 120 Vac emergency lighting panel. In addition, this battery bank provides continuous
24 Vdc power directly to a DC power panel.
Components of this system are listed in Table 9-2
This system automatically provides 120 Vac power for emergency lighting in the ROWPU space and voids and 24 Vdc
power for direct current equipment.
9-3.3 155 kW Ship Service Generators. Two diesel powered generator sets, each rated at 155 kW, serve as primary
electrical power sources for the barge. When shore power is not used, one SSG must be online when any of the
ROWPU major systems are being operated. These SSG's, number 1 in void 4 port and number 2 in void 4 starboard,
are Caterpillar diesel engine driven generator sets. Each SSG consists of a Caterpillar 3306TA diesel engine and a
Caterpillar Model SR4 generator mounted, with isolation isolators, on a common base. The set weighs 3960 pounds dry
and 4180 pounds wet and is 118 inches long, 39 inches wide, and 59 inches high. The third generator set, rated at 20
kW, supplies power for the barge when ROWPU major systems are not operating and there is a lower demand for
9-3.4 20 kW Service Auxiliary Generator. The 20 kW SAG set supplies limited amounts of electrical power for the
barge when ROWPU systems are not in operation. It provides sufficient power for operating normal lighting, dayroom
equipment, workshop equipment, and battery chargers. It must never be used to provide power for any major system
This generator set consists of a Perkins Model 4.236M engine and a Newage Stamford SC144E generator mounted, with
vibration isolators, on a common base. It has free standard switching gear and is capable of parallel operations. The set
weighs 1300 pounds dry and 1451 pounds wet and is 74 inches long, 26 inches wide, and 40 inches high.