Comtest Networks MTAS-192 METALLIC TEST ACCESS SYSTEM - Manual (Page 52)

Comtest Networks CT-IG-MTAS192-2008-v1_8.doc
MTAS-192
46 Installation Guide May 2008
Inter-Shelf Communications Link (ISCL) Cabling
Standard straight-though 10/100BaseT Ethernet cabling is used to daisy-chain the
MTAS Inter-Shelf Communications Link (ISCL) between MTAS chassis. The COMM 1
RJ-45 connector of one shelf is connected to the COMM 2 RJ-45 connector of the next
shelf until the last shelf on the daisy chain has been connected as shown in Figure 31.
Shielded 8-wire CAT5 cable must be used for the ISCL installation. The COMM 1 and
COMM 2 RJ-45 jacks are shielded and tied to the chassis ground to accommodate
shielded RJ-45 plugs. On the last shelf in the daisy-chain, the ISCL bus terminator
(dongle) is inserted in COMM 1.
The ISCL cabling sequence for a full daisy-chained system (12 chassis) is listed in
Table 18.
Table 18: ISCL Cabling Sequence
Connect from: To:
Master COMM 1 Slave 1 COMM 2
Slave 1 COMM 1 Slave 2 COMM 2
Slave 2 COMM 1 Slave 3 COMM 2
Slave 3 COMM 1 Slave 4 COMM 2
Slave 4 COMM 1 Slave 5 COMM 2
Slave 5 COMM 1 Slave 6 COMM 2
Slave 6 COMM 1 Slave 7 COMM 2
Slave 7 COMM 1 Slave 8 COMM 2
Slave 8 COMM 1 Slave 9 COMM 2
Slave 9 COMM 1 Slave 10 COMM 2
Slave 10 COMM 1 Slave 11 COMM 2
Slave 11 COMM 1 ISCL Terminator Dongle
IMPORTANT: When using shielded cable, ensure devices on either end of the cable
have the same reference ground (earth / chassis / frame ground) in order to prevent
ground loops.