Overland Data DLT LibraryXpress Series, Service Manual

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30 Chapter 2 - Installation
Control Cables
Connect each slave module to the Global Control Module using one of the cables with a DB-9
male connector at the slave end and a DB-9 female at the Global Control Module end. A cable
is required for each slave module. Note: Any of the control cables may be connected to any of
the DB-9 connectors on the back panel of the Global Control Module. The Global Control
Module determines the location of each module during power-up tests.
Power Cord
The detachable AC power cord is a standard grounding AC cord which attaches to an IEC-
compatible connector on the rear panel. Connect a cord to the connector on each module, and
connect the other end to a reliably grounded AC outlet or rack power outlet.
To maintain safety compliance, use a power cord with a suitable rating that is approved for
the country in which the product is used. In the US cords must be UL listed, in Canada, CSA
certified, and in Europe use a Harmonized cord marked <HAR> or a nationally certified cord.
SCSI Interfaces
DLT LibraryXpress Modules may be ordered with a choice of single-ended or differential
SCSI-2 interfaces, or, if 7000 series drives are used, single-ended or differential Fast/Wide
SCSI. Both SCSI-2 interfaces use two parallel female high-density 50-pin D-series connectors
per bus. SCSI-2 cables and terminators are secured to the connectors by spring-loaded
latches. Fast/Wide SCSI is available only as differential, and uses two parallel female high-
density 68-pin D-Series connectors per bus. Fast/Wide SCSI cables and terminators are
secured to the connectors by jackscrews.
Note: The internal wiring length of any rack-mounted SCSI system can approach the
maximum length specification of a single-ended SCSI bus. The maximum length specification
for a differential SCSI bus is four times longer. Overland Data strongly recommends that you
use differential controllers and high-quality SCSI cables to ensure the highest performance of
your LibraryXpress. Bus errors caused by excessive length or poor quality cables can
significantly degrade performance and reliability.