
When connecting two Model 1008s, it is necessary to use a crossover cable. The diagrams below show how a crossover cable should be constructed for the following environments: 
| 
 | 
 | ||
| SIGNAL | PIN# | PIN# | SIGNAL | 
| GND† | 6 | GND† | |
| RCV- | 4 | XMT- | |
| XMT+ | 5 | RCV+ | |
| XMT- | 2 | RCV- | |
| RCV+ | 3 | XMT+ | |
| GND† | 1 | GND† | |
†Connection to ground is optional
| 
 | 
 | ||
| SIGNAL | PIN# | PIN# | SIGNAL | 
| GND† | 7 | GND† | |
| RCV- | 5 | XMT- | |
| XMT+ | 6 | RCV+ | |
| XMT- | 3 | RCV- | |
| RCV+ | 4 | XMT+ | |
| GND† | 2 | GND† | |
| 
 | 
 | ||
| SIGNAL | PIN# | PIN# | SIGNAL | 
| XMT+ | 3 | XMT+ | |
| XMT- | 4 | XMT- | |
| 
 | 
 | ||
| SIGNAL | PIN# | PIN# | SIGNAL | 
| XMT+ | 4 | XMT+ | |
| XMT- | 5 | XMT- | |
†Connection to ground is optional
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4.2 WIRING FOR MULTIPOINT CIRCUITS
The Model 1008 supports 
4.2.1 STAR TOPOLOGY
Using a star topology, you may connect several Model 1008s together in a master/slave arrangement. Maximum distance between the units will vary based upon the number of drops, data rate, wire gauge, etc. Call Technical Support for specific distance estimates.
Figure 5 (below) shows how to wire the two-pair  cables properly for a Model 1008 star topology. Note that the ground connection is not needed.
| HOST | 
 | FIRST SLAVE | SECOND SLAVE | 
| XMT+ | 
 | RCV+ | RCV+ | 
| 
 | |||
| XMT- | 
 | RCV- | |
| 
 | |||
| 
 | RCV- | ||
| 
 | |||
| RCV+ | 
 | XMT+ | |
| 
 | |||
| 
 | XMT+ | ||
| 
 | |||
| RCV- | 
 | XMT- | |
| 
 | |||
| 
 | XMT- | ||
| 
 | |||
| 
 | 
 | 
 | |
| 
 | 
 | 
 | |
| Figure 5. Star wiring for Model 1008 host and slaves | |||
4.2.2 DAISY CHAIN TOPOLOGY
Using a daisy chain topology, you may connect several Model 1008s together in a master/slave arrangement. Maximum distance between the units will vary based upon the number of drops, data rate, wire gauge, etc. Call Technical Support for specific distance estimates.
(Continued)
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