Alarm port, Switch card – HP NonStop G-Series User Manual
Page 56
Switch Modules
ServerNet Nomadic Disk (Release 2) User’s Guide — 523968-001
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Alarm Port
Alarm Port
If an optional external alarm is connected to the external alarm port and the alarm
relays are energized, the alarm is activated under the following conditions:
•
SWCI sends a command to activate the alarm.
•
Sensor 1 or Sensor 2 temperature is out of range.
•
Voltage for the power supply is out of range.
•
The switch module fails the power-on self-test (POST).
•
Certain environmental faults occur. For these faults, refer to
Switch Card
Switch cards, which occupy slots 1 through 8 of a switch module, control the path of
fiber-optic signals between the internal 46xx or external 45xx disk drives and one of
two nodes.
A switch card has two switch positions: straight and crossed. In the straight position, J1
connects to J2 and J3 connects to J4; in the crossed position, J1 connects to J4 and
J3 connects to J2. By switching between the two positions, the switch card determines
which node has access to the disk drives. To ensure access to the disk drives, each
switch module contains two switch cards connected to the same set of drives.
The switch card faceplate is shown in
.