UDACT-2 — Instruction Manual
P/N 54089:B3 10/29/2019
19
TB1 - 24 VDC Power Connections
Installation and Wiring
2.2 TB1 - 24 VDC Power Connections
24 VDC filtered, non-resettable power is connected between the Main Power
Supply of the panel and the UDACT-2 using twisted pair wire.
One +24V and one Common terminal are used for input from the power
source. The other terminals may be used as pass throughs to the next device
from the power source.
2.3 TB2 - EIA-485 Connections
Communications between the UDACT-2 and the host control
panel is accomplished over a two wire EIA-485 serial interface
which is power-limited and supervised by the control panel and
the UDACT-2. The wiring connections are made to the EIA-485
+, EIA-485 –, and REF terminals of TB2 on the UDACT-2.
The EIA-485 circuit cannot be T-Tapped and must be wired in a
continuous fashion from the control panel to the UDACT-2 and, if
installed, annunciators. Limit the total wire resistance to 100
Ohms on the EIA-485 circuit. Do not run cable adjacent to, or in
the same conduit as 120 volts AC service, noisy electrical circuits
that are powering mechanical bells or horns, audio circuits above
25 volts RMS, motor control circuits, or SCR power circuits.
2.4 TB2 - Earth Connection
An earth ground connection to the UDACT is required for transient protection. TB2 provides a
connection to ground for lightning protection.
2.5 Telephone Connections - J3 and J4
Provision to connect to two independent telephone lines is available via two telephone jacks labeled “PRI” (Primary) and “SEC” (Sec-
ondary). Telephone line control/command is possible via double line seizure using an RJ31X style interconnection. (RJ31X jacks must
be ordered separately).
U
D
A
C
T-2
TB1.
w
m
f
+24 VDC Power
Common
Figure 2.12 TB1 Power Connections
NOTE:
Only one UDACT-2 can be installed on a host’s EIA-485 ACS circuit.
U
D
A
C
T-TB2
.wmf
Figure 2.13 TB2 EIA-485 Interface Connections
EIA-485
connections
between
UDACT-2
and host
panel
+
-
Reference
Reference
+
-
EIA-485 connections between UDACT-2 and next device
UDA
CT-0
2
.cd
r
Figure 2.14
TB2 Earth Connection
Connect
to ground
NOTE:
It is critical that the UDACT-2 be located as the first device on the incoming telephone circuit to properly function.
