American Dynamics 1689B, Руководство по установке

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CABLE CONNECTIONS
Code Line Connections
The Control Code line connection to the receiver is made with
user-supplied, shielded 2-wire twisted pair, Belden 8760 or
equivalent (for Plenum, use Belden 88760 or equivalent). The
maximum code line length is 5000 feet.
The code line connector, J4, is a 4-position terminal strip
located near the rotary switches S1 through S16 (see Figure 1
or OP0064, OP0065 or OP0066). The PCB is marked B (black
code), W (white code), and S (shield) for the pin positions of
this connector.
Before starting:
1. Check power line to verify the power is off.
2. Open the receiver and find the code terminal connector,
located on the PCB, labeled J4.
Wiring:
1. Pass the code wire through the bushing to the code
connector. Do not tighten bushing.
2. Insert the Black Code wire into the screw terminal marked
B.
3. Insert the White Code wire into the screw terminal marked
W.
4. Insert the Shield wire into the screw terminal marked S.
5. Remove any excess cable and tighten the bushing.
The 1689B receiver has a 120-ohm terminating resistor
installed on the PCB and is designed for “Star” or “Home
Run” connection to a code distribution unit (see Figure 3).
If the receiver is to be used in a “daisy chain,” the 120-ohm
terminating resistor must be removed from all but the last
receiver (see Figure 4). A 120 ohm termination must be
provided on the last piece of equipment on each line.
The 120-ohm resistor for the 1689B is located on the PCB in
the lower left corner of the board and is designated R1.
The green Code LED on these receivers is lit when the unit is
receiving valid code. A flickering Code LED indicates a
problem in the transmission of the code, poor or loose
connections, improper termination, or a defective receiver.
CONNECTIONS
4
REC
*
REC
*
REC
*
* 120 Ohm Termination
Code
Distribution
Unit
Receiver
Receiver
Receiver
Code
Distribution
Unit
W B S W B S W B S
Figure 3 - Code Distribution Unit "Star" Connection
Figure 4 - Code Line “Daisy Chain” Connections
CAUTION - Due to the presence of non-insulated
components with hazardous voltages, the
following internal adjustments should be
performed by qualified service personnel only.