Compaq StorageWorks TL881/TL891 Family MiniLibrary System Reference Guide (July 2000)

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Compaq StorageWorks TL881/TL891 Family MiniLibrary System Reference Guide
Compaq Confidential – Need to Know Required
Writer:
Bob Young
Project:
Compaq StorageWorks TL881/TL891 Family MiniLibrary System Reference Guide
Comments:
Part Number:
127510-002
File Name:
d-ch3 Installation.doc
Last Saved On:
7/12/00 11:24 AM
Interface Cable Specifications
The MiniLibrary is a high-performance system. To avoid degradation of
performance, use the highest-quality interface cables. The detailed
requirements for SCSI cables are set forth in ANSI X3.131-1994. All SCSI
cables used with the MiniLibrary module meet at least the following
requirements:
■
Shielded or double-shielded, as required to meet EMI specifications
■
Impedance match with cable terminators of 132 Ω
■
Characteristic impedance between 90 and 132 Ω, required
■
Each end of the twisted pair ground must be connected to chassis
ground.
■
The maximum cable length for a single-ended Fast SCSI bus is
9.8 ft (3 m).
■
The maximum cable length for a differential Fast SCSI bus is
82 ft (25 m).
NOTE:
See Appendix H, “Interconnect Characteristics for Signals,” for LVD/SE, SE, and
HVD recommended minimum conductor sizes.
IMPORTANT:
When calculating the overall length of the bus, be sure to include the
internal cabling of the module, as follows:
■
MiniLibrary Base Module:
TL881:
DLT0 19 in (48 cm)
DLT1 27 in (69 cm)
TL891/DLT8000:
DLT0 17 in (43 cm)
DLT1 26 in (66 cm)
SCSI Jumper:
12 in (30 cm)
Robotics Control:
Wide SCSI 35 in (89 cm)