IBM 7012 397, Site And Hardware Planning Information

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Computer Room Emergency Power Off (EPO)
When the integrated battery feature (IBF) is installed and the room EPO is tripped, the batteries will
engage and the computer will continue to run. It is possible to attach the computer room EPO system to
the machine UEPO. When this is done, tripping the room EPO will disconnect all power from the line cords
and the internal battery backup unit. In this event all volatile data will be lost.
To incorporate the IBF into the room Emergency Power Off systems (EPO), a cable must be made to
connect to the back of the system UEPO panel. The following diagrams illustrate how this connection is
made.
The preceding figure illustrates the back of the machine UEPO panel with the room EPO cable plugging
into the machine. Notice the switch actuator. After it is moved to make the cable connection possible, the
room EPO cable must be installed for the machine to power on.
In the following figure, an AMP connector 770019-1 is needed to connect to the system UEPO panel. For
room EPO cables using wire sizes #20 AWG to #24 AWG use AMP pins part number 770010-4. This
connection should not exceed 5 Ohms, which is approximately 200 ft.(61 m) of #24 AWG.
1
2
AMP Connector
Part Number - 770019-1
Contact Number
2 Pole Normally Closed Pushbutton
3 4
Battery Holdup Times
The following tables illustrate typical machine holdup time vs load in minutes for fresh and aged batteries.
All times listed are in minutes. Machine load is listed in total AC input power (power for both line cords
combined). A fresh battery is defined as 2.5 years old or less, while an aged battery as 6.5 years old.
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Site and Hardware Planning Information