System Box,
Continued
Mass Storage
Device Areas
The Model 90 system box can hold two half-height, fixed media
drives (8.9 cm [3.5 in]) in the H bracket (front left, Figure 3–1),
and one half-height, removable media drive (13.3 cm [5.25 in] or
8.9 cm [3.5 in]) in another bracket (front right, Figure 3–1). The
bottom drive in the H bracket is mounted upside down. The H
bracket releases by a single latch and the other bracket uses two
release points.
Power Supply
The system box has space for one power supply, the H7819-AA.
The power supply provides protection against excess voltage,
current, and temperature.
The power supply voltage connectors are located at the rear of the
unit. The input connector is used to connect to a wall outlet and
the output connector connects to the system monitor. The power
switch and power OK LED are located on the front of the unit.
Inside, is a -9.0 V LED. The supply also has two 12 V fans for
cooling the system.
The power supply has an automatic voltage select (AVS ) circuit
to automatically select the ac input for 100 Vac to 120 Vac or 220
Vac to 240 Vac mode of operation. The power supply is a 174 watt
unit.
Voltage (dc)
Ampere
+5.1
19.00
+3.3
4.89
+12.1
3.82
-12.0
0.69
-9.0
0.18
Power is supplied to the following components:
System module (which supplies power for option modules
installed in the system and mass storage devices)
Cooling fans
Continued on next page
3–3