Digital Equipment EK-SFXXS-SG-003, Service Manual

Page: 35 / 224

Theory of Operation 2–11
2.2.4 Rear Panel Controls and Indicators
Figure 2–4 shows the rear panel of the storage enclosure. The DSSI
connectors are on the top rear side of the enclosure. The ac power switch,
line voltage selector switch, and power supply fault indicator are on the
bottom rear of the enclosure, on the power supply chassis, as shown in
Figure 2–4. These controls and indicators affect operation of the entire
storage enclosure.
Table 2–4 summarizes the rear panel control/indicator functions. Details
are provided in the paragraphs that follow.
Table 2–4 Summary of Rear Panel Control/Indicator Functions
Control/Indicator Function
Power Supply Chassis
AC power switch Applies line voltage to dc power supply.
Line voltage
selector switch
Selects between 120 Vac (60 Hz) and 240
Vac (50 Hz) line voltage.
Power supply
fault indicator
Illuminates for fault or overtemperature
in enclosure.