Ciena CN 3960 - Page 35

CN 3960 Hardware Installation Guide 31
I NSTALLATION
P OWER S UPPLY
2
Removing a DC Power Supply
Power supplies are hot-swappable, allowing one power supply to be removed and
replaced while the remaining supply will compensate to maintain uninterrupted system
operation. However, care must be taken to avoid personal injury when removing a power
supply while the unit is powered by the second unit.
WARNING: Keep hands and fingers out of the power supply slots as voltage is present on
the switch backplane when the system is operating.
WARNING: Before performing the procedure, ensure that all power is off to the DC
circuit. Locate the circuit breaker on the panel board that services the DC circuit and
switch it to the OFF position. Tape the circuit breaker switch handle in the OFF position
to prevent accidental closing of the circuit.
1. Remove power from the DC circuit supplying power to the device.
2. If the power cable is attached to the power supply using a cable tie, use cutters to
remove the secured power cable from the handle of the power supply.
3. Use a Phillips screwdriver to loosen the set screw s on the terminal block, then
disconnect the power input wi res.
4. Use a Phillips screwdriver to loo sen the single captive hold-down screw that secures
the power supply.
5. Grasp the power supply handle and pull the supply straight out of the bay, supporting
the supply with your other hand.
6. Do one of the following:
• Install a replacement unit immediately. S ee the In s t all ing a DC Pow e r Su ppl y section
on page 29 for installation instructions.
• If the bay is to remain empty for any length of time, install the power supply cover
plate that was removed when the second supply was initially installed over the empty
power supply slot.
You have now safely removed the power supply and secured the power supply slot from
da m ag e b y inst a l l ing the cover p l at e .