Submittal Sheet

AT120A-E; AT140A-E; AT150A,B,D-F; AT160B; AT175A-D,F TRANSFORMERS
11 68-0054—06
Fig. 16. Mounting “E” model transformer in a panel cutout.
Conduit/Panel Mounting
Mount the transformer on a plate or panel (not included) with
a 7/8 in. knockout. The transformer has a 1/2-14 NPSM
conduit connector and lock nut.
NOTE: To meet UL requirements, mount the transformer on
a plate or panel with a maximum thickness of 0.15 in.
This allows three and one-half threads of the conduit
spud to be exposed after the transformer is mounted.
1. With the conduit connector side of the transformer fac-
ing the plate, thread the leadwires through the plate
knockout.
2. Insert the connector in the knockout.
3. While holding the plate in place, assemble and tighten
the lock nut to fasten the transformer securely. See
Fig. 17. Avoid damaging the leadwires with the screw-
driver.
4. Make line voltage primary connections within an
approved enclosure.
Fig. 17. Conduit/panel mounting (plate not included).
Fig. 18. Schematic for single and multitap transformers.
WIRING
All wiring must comply with local codes and ordinances.
Disconnect power before making wiring connections to
prevent electrical shock or equipment damage.
1. Make primary connections to the line voltage power
supply. On multitap models, make sure to use the cor-
rect leads or terminals for the available power supply.
Refer to Fig. 18.
2. On multitap models with leadwires, insulate the ends of
the unused leads by taping or capping with a solderless
connector.
3. Make secondary connections to 24 Vac control circuit.
M12127A
MOUNTING
PLATE (NOT
INCLUDED)
END
BELL
LEADWIRES
FOR PRIMARY
AND SECONDARY
CONNECTIONS
LOCK NUT
CONDUIT
CONNECTOR
M6906
A
RESET
BUTTON
VOLTAGE
VARIES
WITH MODEL
2
SECONDARY
M12108B
COMMON
PRIMARY
BLACK
120V - WHITE
208V - RED
240V - ORANGE
277V - BROWN
480V - BLACK/RED
1
3
SINGLE VOLTAGE MODELS
208V
2
SECONDARY
COMMON
PRIMARY
BLACK
ORANGE
1
3
208/240 VAC MODELS
240V
RED
208V
120V
2
SECONDARY
COMMON
PRIMARY
BLACK
ORANGE
1
1 SECONDARY CONNECTIONS ARE SCREW TERMINALS, 1/4 INCH
QUICK-CONNECTS OR BLUE AND YELLOW LEADWIRES.
BLACK IS COMMON WITH RESPECT TO THE TRANSFORMER
WINDING ONLY AND NOT THE EXTERNAL CIRCUIT.
SOME MODELS AVAILABLE WITH 1/4 INCH QUICK-CONNECTS.
2
3
3
120/208/240 VAC MODELS
240V
RED
WHITE
277V
208V
2
SECONDARY
COMMON
PRIMARY
BLACK
BLACK/RED
1
208/277/480 VAC MODELS
480V
BROWN
RED