IBM FlashSystem 900, Service Manual

Page: 494 / 546

FRU Exchange
Exchange a DCPW
Important
Check that the 'Power Control' display is
set to local (3) on the control panel.
If not, do the following:
¹
Press the 'Power Control' key until (3) is
displayed in the power control window.
¹
Press the 'Validate' key.
If the state of the machine does not allow you
to display or to change the 'Power control'
mode, continue with the following procedure.
1. If the machine has its
¹
Ready LED ON, go to step 2.
¹
Otherwise, go to step 3.
2. Activate the maintenance switch.
a. Open the front cover and locate the lever
of the maintenance switch on the
DCDP.
.1/
b. Pull the lever outwards.
This will prevent the main -48v from drop-
ping and will stop the power monitoring.
3. Locate the DCPW that you have to exchange
using Figure 4-9 on page 4-8.
4. Switch the main circuit breaker CB1 OFF at
the DCPW.
.2/
5. Switch the -48 Volts DC source circuit breaker
OFF or ask the customer to do so..
6. Attach a warning label directly to the circuit
breaker indicating that "power must not be
applied".
7. Disconnect the power supply cable from the
customer junction box.
8. At the rear of the machine, loosen the four
screws which secure the cover plate.
9. Remove the cover plate.
10. Check that on the rear TB of the DCPW there
is no voltage
.3/
between the black and red
wire.
11. Disconnect the black and the red wire from
the DCPW.
.3/
12. Unplug connectors J9 and J10 from the rear
of the DCDP.
13. Remove the screw holding the DCPW.
.4/
14. At the front of the machine, unplug the J1
connector and remove the two screws holding
the power box. Slide the DCPW out.
To install the new DCPW, perform this procedure
in the reverse order.
¹
Return to the step in the MAP you were per-
forming.
4-28
3746-900: Service Guide