Installation guide

Installation
Manual No. 775020 2-25
8. AcceleRAID 150 Termination (SISL)
Check to confirm that all drive channels are properly terminated as
shown in Figure 2-22. The AcceleRAID 150 is equipped with
automatic SCSI termination circuitry for the SCSI channel that resides
on the AcceleRAID board. If the controller board is at the end of the
SCSI bus, it automatically enables on-board termination.
If all the SCSI devices on a channel are connected either to the internal
connector or to the external connector, the end of the SCSI bus farthest
from the controller board must have a terminator installed. In this case,
the controller board automatically enables on-board termination.
If some SCSI devices on the channel are connected to the internal
connector, and some are connected to the external connector, the
two ends of the SCSI bus farthest from the controller board must each
be terminated. In this case, the controller board automatically disables
on-board termination. See Figure 2-22 for an example of an internal –
external drive configuration. Notice the terminator “T” symbol
indicating termination at the farthest bus ends. External drive cabinets
usually have termination built into the end of the SCSI bus.
☛
Note
The illustrated internal and external connectors are
both on the same channel.
It is better to terminate the ends of the SCSI bus itself
than it is to terminate the end devices on the bus. This
allows hot swap devices to be added or removed from
the SCSI bus without affecting termination.
Figure 2-22. Termination with Internal - External Drive Configuration
T
T