Specifications

Alto 818 Installation and Operation
3-14 P/N 66109074001 Rev. D
S-Net cable should be installed as a single cable; splices should be soldered or secured with
crimp lugs. Drop-lines to a S-Net devices should not exceed 6 feet (1.8 meters) in length.
Figure 3-1: Drop Wiring
3.6.6 TERMINATION RESISTORS
The S-Net should be terminated with a 120-ohm, ¼ watt resistor connected between the wires
(DATA A and DATA B) at the last node device on each branch of the S-Net.
3.6.7 NEXSTAR RS-485 MULTIPLEXER
The NexStar multiplexer may be used to create multiple S-Net branches and increase overall
network length. All S-Net runs must be terminated at each end with a 120-ohm, ¼ watt resistor
between the data lines. Figure 3-2 shows a sample block diagram indicating where termination
resistors must be installed. See the NexStar manual for further information.