1/0 Cable Requirements; Cable; Connector Requirements - Seagate ST251N Product Manual

1.11 1/0 CABLE REQUIREMENTS
1.11.1 CABLE
A 50-conductorflatcable or 25-conductortwisted pair cable is required.
The maximum cable length is 6 meters (19.7 ft). Each SCSI bus con-
nection may have a 0.1 meter (0.33 ft) maximum stub length.
The characteristic impedance for unshielded flat or twisted pair ribbon
cable should be 100
0
±10%. A characteristic impedance greater
than 90
0
is preferred for shielded cables. To minimize discontinuities
and signal reflections it is desirable to minimize the use of cables of
different impedances in the same bus.
1.11.2 CONNECTOR REQUIREMENTS
The drive connector is a 50-conductor connector with two rows of 25
male pins on 100 mil centers.
The cable connector is a 50-conductor nonshielded connector consist-
ing of two rows of 25 female contacts on 100 mil centers. Recom-
mended strain-relief connectors are AMP part number 1-499506-2 or
DUPONT part number 66900-X50.
ST251N/277N Product Manual, Rev. B 1-11