C7089A Outdoor Sensor

APPLICATION

The C7089 Outdoor Sensor is used with the PC8900

Perfect Climate Comfort Center™ Control System and the

W8900 Remote Module. It senses the outdoor temperature for display on the PC8900 at the touch of a key. The sensor is encapsulated to protect against water and contaminants, and includes 60 in. leadwires.

SPECIFICATIONS

Operating Ambient Temperature Range:

-40 to 128

°

F (-40 to 53

°

C)

Operating Relative Humidity:

5% to 95% noncondensing

Dimensions in inches (millimeters):

2-1/4 (57) x 3/8 (10) with 60 (1524) leadwires

INSTALLATION INSTRUCTIONS

INSTALLATION

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 connecting wiring to prevent electrical shock or equipment damage.

Location and Mounting (Fig. 1)

Mount the sensor where:

• setting can not be tampered with.

• there is good air circulation.

• it can measure the true outdoor ambient temperature.

• surface is flat.

• the wire distance between the C7089 and W8900 is less than 200 feet.

Do not mount the sensor:

• in the direct sunlight.

• where hot or cold air blows on the sensor. Discharge line from an outdoor compressor unit, vent or fan will cause inaccurate temperature readings.

• where snow, ice or debris can cover it.

Use the following steps to mount the sensor:

1

Remove the sensor from the mounting clip.

2 Mark the area on the surface where the C7089 mounting clip will be mounted.

3 Mount the clip.

®U.S. Registered Trademark

Copyright © 1995 Honeywell Inc. • All Rights Reserved

X-XX UL

69-0896-1

C7089 OUTDOOR SENSOR

CAUTION

Disconnect the power supply before connecting the wiring to prevent electrical shock or equipment damage.

Wiring must comply with applicable codes, ordinances and regulations.

1 Wire the C7089 Outdoor Sensor to the terminals marked OUT on the W8900 Remote Module. If the leadwire provided with the C7089 is not long enough, run cable to a hole at the selected C7089 location. Color-coded, 18-gauge thermostat wire is recommended. For an example of general wiring of the C7089, see Fig. 2. Pigtail wiring can be used.

2 Mount the C7089 in its mounting clip.

3 Plug wiring hole using nonhardening caulk or putty.

1

C7089

2

WIRING HOLE

THROUGH

STRUCTURE

M7514

Fig. 1. Typical locations for outdoor sensor.

Wiring

CAUTION

Keep wiring at least one foot away from large inductive loads such as motors, line starters, lightning ballasts, and large power distribution panels. Failure to follow these wiring practices can introduce electrical interference (noise), which can cause erratic system operation. Use shielded cable to reduce interference when rerouting is not possible. Ground the shielded cable to the GND terminal on the W8900.

IMPORTANT

Erratic temperature readings from a sensor can occur as a result of any of the wiring practices described below. These practices must be avoided to assure proper operation. Use shielded cable to reduce interference when rerouting of sensor wiring is not possible.

a. Do not route temperature sensor wiring with building power wiring, next to control contactors or near light dimming circuits, electric motors or welding equipment.

b. Avoid poor wiring connections.

c. Avoid intermittent or missing building earth ground.

GND

W8900

OUT

OUT

LED

3

1 USE APPROPRIATE MOUNTING MEANS FOR THE TYPE

OF STRUCTURE.

2

PLUG WIRING HOLE WITH NONHARDENING CAULK OR PUTTY.

3 IF SHIELDED CABLE IS REQUIRED, GROUND TO GND TERMINAL

ON W8900.

M4457

Fig. 2. Wiring diagram for the C7089 Outdoor Sensor to the W8900 Remote Module.

69-0896—1 2

C7089 OUTDOOR SENSOR

OPERATION

The C7089 Outdoor Sensor converts outdoor ambient temperature to a resistance that the W8900 Remote

Module can interpret. The W8900 Remote Module in turn sends a signal to the PC8900 where the outdoor temperature is displayed when the CHECK key is pressed. The

C7089 has a positive temperature coefficient (PTC), which means that the resistance increases as the temperature increases. Fig. 3 shows the resistance characteristics of the C7089 Sensor.

3900

3800

3700

1

3600

3500

M6358

3400

3300

3200

3100

3000

2900

2800

-40

(-40)

-20

(-29)

0

(-18)

20

(-7)

40

(5)

60

(16)

80

(27)

TEMPERATURE

100

(38)

120

(49)

140

(60)

160

(79)

°F

(°C )

1 RESISTANCE INCREASES 4.84 OHMS PER 1°F CHANGE OR 8.7 OHMS PER 1°C CHANGE.

OUTDOOR TEMPERATURE OHMS OF

RESISTANCE

°F

50

55

60

65

70

20

25

30

35

40

45

-10

-5

10

15

0

5

-40

-35

-30

-25

-20

-15

105

110

115

120

120

130

75

80

85

90

95

100

135

140

145

150

°C

-40.0

-37.2

-34.4

-31.7

-28.9

-26.1

-23.3

-20.6

-17.8

-15.0

-12.2

7.2

10.0

12.8

15.6

18.3

21.1

-9.4

-6.7

-3.9

-1.1

1.7

4.4

40.6

43.3

46.1

48.9

51.7

23.9

26.7

29.4

32.2

35.0

37.8

54.4

57.2

60.0

62.8

65.6

3462 to 3437

3486 to 3462

3510 to 3486

3534 to 3510

3558 to 3534

3583 to 3558

3607 to 3582

3631 to 3607

3655 to 3631

3679 to 3655

3703 to 3679

3728 to 3703

3752 to 3728

3776 to 3752

3800 to 3776

3824 to 3800

3849 to 3824

2929 to 2905

2953 to 2929

2978 to 2953

3002 to 2978

3026 to 3002

3050 to 3026

3074 to 3050

3099 to 3074

3123 to 3099

3147 to 3123

3171 to 3147

3195 to 3171

3220 to 3195

3244 to 3220

3268 to 3244

3292 to 3268

3316 to 3292

3341 to 3316

3365 to 3341

3389 to 3365

3413 to 3389

3437 to 3413

Fig. 3. C7089A sensor resistance vs. temperature performance characteristics.

3 69-0896—1

C7089 OUTDOOR SENSOR

CHECKOUT

Allow the C7089 Outdoor Sensor to soak in the outdoor air for a minimum of five minutes before taking a reading.

With an accurate thermometer (

±

1

°

F [0.5

°

C]), measure the temperature at the sensor location, allowing time for the thermometer to stabilize before reading. Press the CHECK key on the PC8900 until the display shows OUT followed by the temperature reading. See Fig. 4. The PC8900 reading should match the reading taken outdoors.

To verify the resistance of the sensor, remove one wire from one of the C7089 wiring terminals. Use an ohmmeter to measure the resistance across the sensor. Then verify sensor accuracy with the temperature/resistance curve of

Fig. 3.

CALIBRATION

The C7089 Outdoor Sensor is calibrated in the factory and cannot be recalibrated in the field.

SYSTEM

CHECK

PC8900

M7515

Fig. 4. Outdoor temperature display on the PC8900.

Home and Building Control

Honeywell Inc.

1985 Douglas Drive

Golden Valley, MN 55422

Home and Building Control

Honeywell Limited-Honeywell Limitée

740 Ellesmere Road

Scarborough, Ontario

M1P 2V9

4