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69-0251—2
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Home and Building Control
Home and Building Control
Helping You Control Your World
Honeywell Inc.
Honeywell Limited—Honeywell Limitée
1985 Douglas Drive North
740 Ellesmere Road
Golden Valley, MN 55422
Scarborough, Ontario
M1P 2V9
Printed in China
Fig. 6—Schematics for single and multitap
transformers.
Checkout
CAUTION
Do not short transformer secondary terminals.
Overload current protection is inherent on AT120,
AT140, and AT150. A fused 3.5 Amp secondary
is used on AT175.
VOLTAGE CHECK
After installation is complete, turn on power supply and
perform a voltage check.
1. Place controlled equipment in operation and observe
through one complete cycle.
2. Using a voltmeter, assure proper primary and sec-
ondary voltages exist.
3. If voltage readings are incorrect, assure primary volt-
age connections are made properly.
4. Measure voltage again.
• If proper primary voltage is measured and sec-
ondary voltage is significantly less than the volt-
age shown on the regulation curves, transformer
winding is damaged. Replace transformer and
repeat checkout procedures.
• If primary voltage is 0V, assure power supply is
connected properly or repair if necessary. Repeat
checkout procedures.
5. Do not put system into operation unless correct pri-
mary and secondary voltages are measured.
VOLTAGE
VARIES
WITH MODEL
2
SECONDARY
M9182
COMMON
PRIMARY
BLACK
120 V - WHITE
208 V - RED
240 V - ORANGE
277 V - BROWN
480 V - BLACK/RED
1
3
SINGLE VOLTAGE MODELS
208 V
2
SECONDARY
COMMON
PRIMARY
BLACK
ORANGE
1
3
208/240 VAC MODELS
240 V
RED
208 V
120 V
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
240 V
RED
WHITE