Hitachi AMS 2100, Service Manual

Page: 54 / 192

1–14
Introduction
Hitachi AMS 2000 Family Storage System Service Guide
Expansion unit
The expansion unit (model RKAK) is used with all three base unit models.
It contains from 2 to 15 SAS or SATA disk drives, two redundant power
supplies and two ENC control units. The control units manage the drives and
are also used to connect the expansion unit to the base unit and to other
expansion units.
Figure 1-11 shows the front (above) and rear (below) views of the AMS
2100/2300 expansion unit. The front bezel has been removed in this photo.
Figure 1-11: AMS 2000 Family Expansion Unit Front and Rear Views
Expansion unit front panel
Figure 1-12 shows the front of an expansion unit (factory designation
RKAK) with the decorative bezel installed.
The front panel of the expansion unit includes Power and Locate status LEDs
that show the status of the unit and identify the unit. The installation
location should provide an unobstructed view of these LEDs.
In addition, each drive slot on the expansion unit has alarm and Active LEDs
that show the status of the drive that is installed in the slot that is directly
below the status LEDS. As shown in Figure 1-13 on page 1-15 , these LEDs
are visible when the front bezel is removed. A close up photo of the drive
status LEDs is shown in Figure 1-27 on page 1-31 .