Toshiba DK 16 Power Supply Removal Replacement, DK8 Power Failure Emergency Transfer Option

3 POWER SUPPLY REMOVAL AND

REPLACEMENT

3.00The power supply comes factory-installed in the Key Service Unit (Figure 4-5); if necessary, it can be removed and replaced.

3.10 Power Supply Removal (Figure 4-5)

1)Make sure that the power supply switch is OFF and that the AC power cable is not plugged into an outlet. Confirm that green AC LED is not lit.

2)Loosen the screws on the front cover of the Key Service Unit, and remove the cover.

3)Unplug HPFB cable from BATT connector of power supply and disconnect the HPFB ground wire (Figure 4-5).

4)Unplug the AC cable from the CN1 connector on the power supply (Figure 4-5).

5)Remove the FG screw, and disconnect the green third wire ground ring terminal (Figure 4-5).

6)Unplug the DC cable from the CN3 connector on the power supply (Figure 4-5).

7)Remove the top two, and bottom left corner screws that attach the power supply to the Key Service Unit. Remove power supply.

3.20 Power Supply Replacement (Figure 4-5)

1)Set the power supply in its proper place in the Key Service Unit (Figure 4-5).

2)Secure the power supply to the Key Service Unit with the top two, and bottom left corner screws.

3)Install the green third wire ground ring terminal with the FG screw.

4)Plug the AC cable into the CN1 connector on the power supply (Figure 4-5).

INSTALLATION-DK8 KSU & PCB

SECTION 100-816-204

MARCH 1993

5)Plug the DC cable into the CN3 connector on the power supply (Figure 4-5).

6)Plug the AC power cable into an outlet and turn ON the power supply switch.

7)Test QPSU8 power supply according to the DK8 Hardware Fault Isolation procedure, Sec- tion 100-816-500, Paragraph 6.

8)Plug HPFB cable into BATT connector of power supply and reconnect the HPFB ground wire (Figure 4-5).

9)Reinstall the cover on the key service unit.

4 DK8 POWER FAILURE EMERGENCY

TRANSFER OPTION

4.00A dedicated standard telephone can be con- nected to the Power Failure Transfer Interface (PF1) on the Key Service Unit to provide power failure backup. During normal operation, this tele- phone cannot be used—it does not count as a station; so it does not reduce the system's 10 maximum station capacity. But if there is a power failure, the telephone will automatically be con- nected to CO line 1. When power is restored, the system will automatically resume with its normal station and CO line assignments, and the dedi- cated telephone will become inoperative again.

4.10DK8 Power Failure Emergency Transfer Installation. Install the dedicated emergency stan- dard telephone as follows (see Figure 4-6):

1)Connect a standard telephone to the PF1 connector in the Base Unit.

4.20DK8 Power Failure Emergency Transfer Test.

1)Turn the system power switch off.

2)Lift the emergency standard telephone hand- set, and verify that there is CO dial tone.

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