Installation and Maintenance Manual
Wired Controllers—Communication Wiring
76 UNT-SVX07D-EN
Transformer Recommendations
A 24Vac power supply must be used for proper operation
of the binary inputs, which requires 24Vac detection. In
addition, the spare 24Vac outputs may be used to power
relays and TRIACS.
• AC transformer requirements: UL listed, Class 2 power
transformer, 24Vac ±15%, device max load 24VA. The
transformer must be sized to provide adequate power
to the controller (12VA) and outputs (maximum 12VA
per binary output).
• CE-compliant installations: The transf
ormer must be
CE marked and SELV compliant per IEC standards.
Wiring Requirements
To ensure proper operation of the UC400 controller, install
the power supply circuit in accordance with the following
guidelines:
• A dedicated power circuit disconnect switch must be
ne
ar the controller, easily accessible by the operator,
and marked as the disconnecting device for the
controller.
• 18 AWG (0.823 mm
2
) copper wire is recommended for
the circuit between the transformer and the controller.
Important: The controller must
receive AC power from
a dedicated power circuit; failure to comply
may cause the controller to malfunction. DO
NOT run AC power wires in the same wire
bundle with input/output wires; failure to
comply may cause the controller to
malfunction due to electrical noise.
Connecting Wires
To connect the wires:
1. Disconnect power to the transformer.
2. Connect the 24Vac secondar
y wires from the
transformer to the 24Vac and terminals on the
UC400 controller (refer to the i
llustration below).
3. Do one of the following to ensure
the controller is
adequately grounded:
• Co
nnect a grounding pigtail at some point along the
secondary wire that runs between the controller
terminal and the transformer.
• Ground one of the terminals on the controller to
the enclosure (if the enclosure is adequately
grounded) or to an alternate earth ground.
.
Power ON Check
To perform a Power ON check:
1. Verify that the 24Vac connector and the chassis ground
are properly wired.
2. Remove the lockout/tagout from the line
voltage power
to the electrical cabinet.
3. Energize the transformer to
apply power to the UC400
controller.
4. Observe the UC400 controller
when power is applied
to verify the power check sequence as follows:
a. The power LED lights red for 1 second
b.
The power LED lights green
• If the sequence above is completed as described,
the controller is properly booted and ready for the
application code.
If the power LED flashes red, a fault condition exists.
VAC
24
XFRM
VAC
24
VAC
24
BI
1
BI
2
BI
3
LINK
IMC
+
24
VDC
BI4
AO1
BI
5
AO2
UI
1
UI
2
AI
3
AI
2
AI
1
AI
4
AI
5
P
1
P
2
CNCNO
BO3
CNCNO
BO2
CNCNO
BO1
RELAYS
ADDRESS
TRIAC SUPPLY TRIACS
A
BO9BO8BO7BO6BO5
BO4
ABB
TX
RX
LINK
IMC
SERVI
C
E
SERVICE TOOL
CONNECT AC POWER TO THE TRAIC SUPPLY TO POWER THE TRIACS
BO1 BO2 BO3 BO4 BO5 BO6 BO7 BO8 BO9
1
2
3
4
5
6
7
8
9
IM
C
1
IM
C
1
3
4
5
6
7
1
2
3
4
5
6
7
8
9
8
9
x1
A pigtail connection may be
necessary between earth ground
and/or enclosure ground if the
device is not grounded through
one leg of the transformer wiring.
Alternate ground method.
24Vac
transformer
UNT-SVX07_-EN.book Page 76 Friday, April 27, 2012 9:40 AM