UM353-1
setting a link address in other models are available in the Installation And Service Instructions for that particular
model. Refer to SD15492 for complete installation, wiring, and service instructions for the Local Instrument Link.
Figure 8-22 shows typical wiring for stations connected to the LIL. Link cabling and wiring involves twinaxial
cable and twisted pair wiring. Twinaxial cable is a twisted pair, shielded cable that is used for runs of 2 feet (0.6m)
or more. Unshielded twisted pair wiring is used mainly for interconnecting row mounted stations. Twisted pair
wiring can also be used for runs up to 2 feet in length, for example, between rows of stations.
Two types of twinaxial cables are recommended: Belden 9182 for links up to 1500 feet (457 meters) and Belden
9860 for links up to 4000 feet (1220 meters). Either type of cable may be used on a single link. To prevent noise
interference, electrically distribute stations as follows:
•
no more than 8 stations may be connected within any 10 foot (3m) section of lower or upper link
•
no more than 16 stations may be connected within any 100 foot (30m) section of lower or upper link
•
insert 100 feet of coiled twinaxial cable between clusters of up to 8 stations
Tap boxes can be installed to serve as a connector interface between Link twinaxial cables and twisted pair wiring
connected to screw terminals. Tap boxes provide over-voltage/lightening protection by including eight transient
voltage suppressors and one 130V surge arrestor. Link termination is also provided by two 150Ω resistors.
Tap
Box
LK+
Blue
LK-
White
SG
See Note 1
Notes:
1. Drain wire of shield connects to terminal SG. A short jumper of 16 AWG insulated wire grounds shield to
station earth ground.
2. Drain wire of shield is cut back and insulated.
3. Twisted pair wiring is used to interconnect stations separated by up to 2 ft (0.6 meters). Twinaxial cable
is used for distances greater than 2 ft (0.6 meters). The maximum twisted pair length is 10 ft (3 meters).
4. When there is no tap box at the end of a link, connect a 150 ohm ,±5%, resistor across the link conductors
at the last station.
5. See Local Instrument Link Installation And Service Instruction SD15492 for details.
March 2003
10 ft. (3m) Maximum Twisted Pair Length
See Notes 3, 4, and 5
Model 352P
iPAC Control
Carrier Field Terminals
or 352
NCA
P
P
31
NCB
32
Carrier
Ground
Bus
Earth
Ground
Ground
See Note 3
FIGURE 8-22 LIL Network Wiring
Model 353
or 354
B1
P
NCA
3
B2
NCB
4
AG
G
Earth
Earth
Ground
Installation
Tap
Box
LK+
P
LK-
SG
See Note 2
AG00270a
8-21