Specifications

Back Panel  15
Hardware Overview
For PSU servicing instructions, see “Replacing Power Components (SSG 550 Only)”
on page 48.
The POWER LED on the front panel of an SSG 500-series device glows either green
or red. Green indicates correct function and red indicates PSU failure.
Table 6 describes the LED states on the field-installable AC and DC PSUs.
AC Power Supply Unit
The fixed AC PSU faceplate for an SSG 520 device contains a power switch and a
male power-cord receptacle. The fixed AC PSU does not have a power LED on the
PSU.
Figure 5: SSG 520 Device Fixed AC PSU Faceplate
The field-replaceable AC PSU faceplate for an SSG 550 device contains an ejector
tab handle, an input power light, and a power cord receptacle.
NOTE: Do not mix SSG 550 PSU types. The only supported combinations are AC+AC and
DC+DC.
Table 6: Input Power LED Descriptions
Status Color Description
On steadily Green Input power is on and device is on
Amber Input power is on and device is off
Off Input power is off
O
I
Power switch
Power cord
receptacle