Pub.: 42004-679L2D
M
ODEL
DEX-10
X AND
DEX-20
X
D
RILLER
’
S
I
NTERCOM
S
TATIONS
Page 8 of 13
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Auxiliary Devices
Terminal block TB1 is provided for connection of the speaker, system cable, footswitch, and beacon.
This terminal block accepts a #12-22 AWG wire. Refer to Table 2 for the recommended conductor sizes.
Conductor ends can be stripped and terminated with or without a wire ferrule.
Table 2. Recommended Cable Sizes
Cable Use
Size
System
Digital: 2-conductor twisted pair, No. 22 AWG is typical
Analog: 4-conductor twisted pair (A/B twist; C/D twist), No. 22 AWG is typical
Power
3-conductor, No. 12 AWG is typical
Beacon
2-conductor, No. 18 AWG is typical (for digital models only)
Footswitch
2-conductor, No. 22 AWG is typical
Speaker Cable 2-conductor twisted pair, No. 18 AWG is typical
1.
Install the system cable on TB1 system terminals A-D. Each system cable must be home run to the
Central. Digital stations require termination of a 2-conductor twisted pair cable on system terminals
A and B only. Analog stations require termination of a 4-conductor twisted pair cable (A/B twist &
C/D twist) on system terminals A-D. Refer to Table 3 for the maximum system cable lengths.
Table 3. Maximum System Cable Lengths
Digital Models
Analog Models
Cable Capacitance
22 AWG
20 AWG
22 AWG
20 AWG
30.5 nf/1000 feet
6562 feet
6562 feet
4921 feet
6562 feet
13.7 nf/1000 feet
9843 feet
9843 feet
2.
Install the speaker cable on TB1 Speaker terminals LS1 and LS2. Refer to Table 2 for recommended
conductor sizes.
3.
Install the beacon control cable on TB1 terminals C1 and C2. This control output is available on
digital stations only. Refer to Table 2 for recommended conductor sizes.
4.
Install the footswitch cable on TB1 terminals N.O. and C. Refer to Table 2 for recommended
conductor sizes.
After all connections are made, inspect and clean the machined and threaded surfaces of both the
termination cover and box. Clean the surfaces by wiping with a clean, lint-free cloth. Apply a light coat
of Killark LUBG lubricant to the cover threads. Install and hand-tighten the cover to the box.