Intergraph Zx10 Ultra-Tower, System Manual

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The total cable length on the system’s SCSI bus is the sum of the following:
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SCSI cable for the internal-access bays – 31 inches (0.7 meters).
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SCSI cable for the external SCSI port – 17 inches (0.4 meters)
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SCSI internal/external cable (replaces the external SCSI port cable) – 34 inches (0.8 meters)
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SCSI cable between the system and the first external device
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SCSI cables between additional external devices
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SCSI cable inside each device connected to the cable – typically 8 inches (0.2 meters) or less
To ensure data integrity and optimum performance, do the following:
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Use the shortest cables possible to connect SCSI devices to the system and to each other.
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Use high-quality SCSI cables to ensure adequate shielding (impedance of 110 to 135 ohms).
CAUTION When handling cables, flex them as little as possible. Ensure that cables do not
contact sharp metal surfaces or become excessively bent or twisted. In particular,
SCSI cables should not have any creased bends.
Choosing SCSI IDs
To determine the ID of each SCSI device on the system, restart the system. When the BIOS screen
displays, look for a list of SCSI devices and write down the ID for each device.
By default, some SCSI IDs are already used by system devices:
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The primary system disk drive uses SCSI ID 0
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The SCSI controller uses SCSI ID 7
See the vendor documentation for details on setting a device’s SCSI ID.
Terminating SCSI Devices
If the SCSI port is located below the rear fan (standard), the external SCSI bus is not terminated.
When you connect SCSI devices to the port, terminate the last device connected to the port.
If the SCSI port is located above the power supply (optional), the system shipped with a terminator
module connected to the port. Remove the terminator module to connect SCSI devices to the port.