Terminating Scsi Devices - Siemens SIMATIC Rack PC 840 Manual

Controller
Termination Enabled
Figure 8-2 Internal and External Termination
8.1.5

Terminating SCSI Devices

Read the device's documentation to determine how to enable or disable
termination on your particular SCSI device(s). On most internal SCSI devices the
termination setting is controlled by a jumper or a switch. On other internal SCSI
devices you must physically remove or install resistor module(s). On most external
SCSI devices, a terminating plug (a resistor pack embedded in a small plug) is
installed or removed to control termination (see Figure 8-3).
8.1.6 SCSI Cables
You should only use the integrated cable for internal extensions. Another two 16-bit
SCSI devices may be connected up to this cable. The cable is terminated on the
drive-side.
You should only use top quality 68-pin external SCSI cables for external
extensions. The total external cable length may not exceed 2 meters.
8-14
No Termination
No Termination
No Termination
No Termination
Cable with
Terminator
No Termination
terminated by cable
SIMATIC Rack PC 840 Manual
A5E00104826-03