Alcatel-Lucent 7750 SR-a4 - Figure 60 Removing a -48 VDC PSU (7750 SR-A4); Removing a -48 VDC PSU

Removing and Replacing a PSU
178 7750 SR-a4 and SR-a8 Installation Guide
Removing a –48 VDC PSU
Figure 60 and Figure 61 show how to remove a –48 VDC PSU from the 7750 SR-a chassis.
Table 90 describes the features.
Figure 60: Removing a –48 VDC PSU (7750 SR-a4)
Danger:
• Ensure that all power from the DC circuit is OFF. Locate the circuit breaker on the panel
board that serves the DC circuit. Switch the circuit breaker to the OFF position. For extra
safety, lock out the circuit breaker by taping the handle of the circuit breaker in the OFF
position.
• When wiring the unit, the ground connection must always be made first and
disconnected last.
• The correct wiring sequence is ground/negative to ground/negative and positive/return
to positive/return.
Note: Refer to 7750 SR-a –48 VDC PSU LED and Connectors on page 139 for a
description of the PSU.
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