Maximum Cable Lengths - Adaptec 39160 Manual

Adaptec SCSI Card 39160 User's Reference
The following example shows LVD (Ultra160 and Ultra2) SCSI
devices on Channel B and non-LVD SCSI devices on Channel A.
Ultra160 and Ultra2
Built-in
SCSI devices
terminator
T
T
Terminated
device

Maximum Cable Lengths

The total length of cabling (internal and external) on the SCSI bus
cannot exceed the maximum lengths listed in the following table.
The third column lists the maximum number of SCSI devices you
can connect to the SCSI card.
Maximum
Cable Length Data Transfer Rate
25 m (82.0 ft) Ultra160 SCSI (160 MBytes/sec)
and Ultra2 SCSI (80 MBytes/sec)
12 m (39.4 ft) Ultra160 SCSI (160 MBytes/sec)
and Ultra2 SCSI (80 MBytes/sec)
3 m (9.8 ft) Fast Wide SCSI (20 MBytes/sec)
3 m (9.8 ft) Fast SCSI (10 MBytes/sec)
3 m (9.8 ft) Ultra SCSI (40 MBytes/sec for 16-
bit, 20 MBytes/sec for 8-bit)
1.5 m (4.9 ft) Ultra SCSI (40 MBytes/sec for
16-bit, 20 MBytes/sec for 8-bit)
1
Mixing Fast/Ultra devices with Ultra160 and Ultra2 SCSI devices causes the entire
SCSI bus to default to Ultra SCSI speeds and cable length requirements.
2
Ultra SCSI data transfer rates do not currently support more than seven devices
connected to the SCSI card.
26
Non-LVD
SCSI devices
T
Terminated
devices
T
Terminated
devices
Maximum Devices
Supported
1
1
15
15
7
4
2
5-7