Honeywell AT120A, AT140A, AT150A, AT175A Installation Instructions

AT120A, AT140A, AT150A, AT175A
These transformers are for use in 24 Vac nominal con-
trol circuits. They are typically used in heating/cooling
control systems, but can be used in any application that
does not exceed the load ratings. They meet National
Electrical Code Class 2 "not wet" and Class 3 "wet" re-
Input
Model Voltage
Number (60 Hz)
AT120A 120/208/240
AT140A 120
120/208/240
208/240
AT150A 120/208/240
AT175A 120/208/240
WHEN INSTALLING THIS PRODUCT...
1. Read these instructions carefully. Failure to follow
them could damage the product or cause a hazardous
condition.
2. Check the ratings given in the instructions and on
the product to make sure the product is suitable for your
application.
3. Installer must be a trained, experienced service technician.
4. After installation is complete, check out product
operation as provided in these instructions.
CAUTION
Disconnect power supply before beginning installa-
tion to prevent electrical shock or equipment damage.
The transformer may be mounted in one of three ways:
— foot mount,
— plate mount, or
— mount through outlet box knockout hole.
FOOT MOUNTING
Mount the transformer using screws (not supplied)
through the four 3/16 in. x 3/8 in. holes in the mounting feet.
Make line voltage primary connections within an approved
enclosure. See Fig. 1.
Discard the mounting plate.
TABLE 1—MODEL SPECIFICATIONS.
Primary
Wiring Open
Connections Circuit
9 in. leads
9 in. leads
9 in. leads
9 in. leads
Installation
C. H. • Rev. 2-94 • ©Honeywell Inc. 1994 • Form Number 69-0251—2
Universal Transformers
quirements and are Underwriters Laboratories (UL) Inc.
listed under UL 1585. They can be mounted through a
7/8 in. knockout on the accessory mounting plate (included),
or with the integral mounting feet. See Table 1 for addi-
tional specifications.
Secondary
Voltage
At Rated
Power
Output Connections
27.0 24.0 Screw terminals
27.0 24.0 Screw terminals
27.5 24.0 Screw terminals
27.5 24.0 Screw terminals
Fig. 1—Foot mounting.
USE SCREWS OR
BOLTS THROUGH
SLOTS (4) IN
MOUNTING FEET
LEADWIRES
FOR PRIMARY
CONNECTIONS
MOUNTING
FOOT (2)
1
Wiring Output Rating at
100 Percent Power Factor
Application
20 VA
40 VA
50 VA
75 VA
SCREW TERMINALS
FOR SECONDARY
CONNECTIONS
M9161
69-0251—2