Honeywell C7232A, C7232B Product Data

®

C7232A

C7232B

C7232A,B

Sensor and Controller

CARBON DIOXIDE SENSOR

PRODUCT DATA

FEATURES

• Models available with LCD that provides sensor
readings and status information.

• Non-Dispersion-Infrared (NDIR) technology used to
measure carbon dioxide gas.

• Gold-plated sensor provides long-term calibration
stability.

• Device provides voltage output based on CO

• Models available with SPST relay output.

• Used for CO

• Automatic Background Calibration (ABC) algorithm
based on long-term evaluation reduces required
typical zero-drift check maintenance.

based ventilation control.

2

levels.

2

APPLICATION

The C7232 Sensor and Controller is a stand-alone carbon
dioxide (CO
necessity with HVAC controllers. The C7232 measures the

concentration in the ventilated space or duct. The C7232

CO

2

is used in ventilation and air conditioning systems to control
the amount of fresh outdoor air supplied to maintain
acceptable levels of CO

) sensor for use in determining ventilation

2

in the space.

2

Contents

Application ........................................................................ 1

Features ........................................................................... 1

Specifications ................................................................... 2

Ordering Information ........................................................ 2

Installation ........................................................................ 3

Wiring ............................................................................... 4

Calibration ........................................................................ 6

Checkout .......................................................................... 6

Appendix .......................................................................... 7

® U.S. Registered Trademark
Copyright © 2003 Honeywell International Inc.
All Rights Reserved

63-2571-4

C7232A,B SENSOR AND CONTROLLER

5

SPECIFICATIONS

Models: C7232 Sensor and Controller. A stand-alone carbon

dioxide (CO
(one analog and one spst relay).

) sensor with two jumper-adjustable outputs

2

C7232A: Wall mount model.
C7232B: Duct mount model.

NOTE: Models are available with or without a 4-digit LCD

that indicates the current CO

concentration.

2

Dimensions:

C7232A: See Fig. 1.
C7232B: See Fig. 2.

Sensor Performance Ratings:

Response Time: 2 min.
Carbon Dioxide Sensor:

Operation: Non-dispersive infrared (NDIR).
Sampling: Diffusion.
Range: 0 to 2000 ppm ±5% and ±50 ppm.
Annual Drift: 20 ppm (nominal).

Electrical Ratings:

Power Supply: 24 Vac ±20%, 50/60 Hz (Class 2).
Maximum Power Consumption: 3W.
Peak Current (at 20 ms): 600 mA.
Relay:

Configuration: Shipped N.O. (reconfigure with software.)
Contact Rating: 1A at 50 Vac/24 Vdc.
Minimum Permissible Load: 1 mA at 5 Vdc.

Linear Analog Output:

Voltage: 0/2-10 Vdc (resistive load greater than
5000 ohms).
Current: 0/4-20 mA (resistive load less than 500 ohms).

Connections:

Wiring:

C7232A: 20-gauge cable with six 8 in. leadwires.
C7232B: 20-gauge cable with six 6 in. leadwires.

Mounting:

C7232A: Vertical surface with standard single-gang junction

box.

C7232B: Sheet metal duct with a sampling tube.

Automatic Background Calibration (ABC) default: On.

Approvals:

Underwriters Laboratories Inc. Component Recognition:

UL94-5V, File No. E191465.
CE.
C7232A: NEMA1.
C7232B: NEMA3.

1

(25)

-1/16

(128)

3-5/32 (80)

KNOCKOUTS
FOR
EUROPEAN
APPLICATIONS

2-3/8 (60)

STANDARD

2-3/8

(60)

UTILITY

CONDUIT

BOX
(2X4)

MOUNTING

HOLES

M17540

Outputs (Jumper Adjustable, see Table 2):

Fig. 1. C7232A dimensions in in. (mm).

Analog: 0-10 Vdc (Default: 2-10 Vdc, 500 to 1500 ppm).
Relay: Normally Open Spst (Default: Close at 800 ppm).

3-5/16 (84)

Ambient Ratings:

1-13/16

(46)

Temperature:

Operating: +32°F to +122°F (0°C to +50°C).
Storage: -4°F to +158°F (-20°C to +70°C).

5-5/8
(142)

Relative Humidity (non-condensing): 0 to 95 percent.

CO

Pressure Dependence: 1.4% change in reading per

2

1 kPa deviation from 100 kPa.

M17592

1-5/8

(41)

8 (203)

Fig. 2. C7232B dimensions in in. (mm).

ORDERING INFORMATION

When purchasing replacement and modernization products from your TRADELINE® wholesaler or distributor, refer to the
TRADELINE® Catalog or price sheets for complete ordering number.

If you have additional questions, need further information, or would like to comment on our products or services, please write or
phone:

1. Your local Honeywell Automation and Control Products Sales Office (check white pages of your phone directory).

2. Honeywell Customer Care

1885 Douglas Drive North

Minneapolis, Minnesota 55422-4386
In Canada—Honeywell Limited/Honeywell Limitée, 35 Dynamic Drive, Scarborough, Ontario M1V 4Z9.
International Sales and Service Offices in all principal cities of the world. Manufacturing in Australia, Canada, Finland, France,
Germany, Japan, Mexico, Netherlands, Spain, Taiwan, United Kingdom, U.S.A.

63-2571—4 2

INSTALLATION

B
S
S

L

C7232A,B SENSOR AND CONTROLLER

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.

IMPORTANT

All wiring must agree with applicable codes,
ordinances and regulations.

CAUTION

Health Hazard.
Improper use can create dangerous situations.

Use in application for sensing carbon dioxide only.
For life-safety applications, this device can function
only as a secondary or lesser device.

CAUTION

Electrical Shock or Equipment Damage Hazard.
Can shock individuals or short equipment
circuitry.

Disconnect power supply before installation.

C7232A Cover Removal/Replacement

C7232A Cover Removal (see Fig. 3)

1. Remove button head socket cap screw and set it aside.

2. Insert the head of a small screwdriver into the slot at the

center and near the top of the cover.

3. Gently pull the handle down toward the bottom of the
device until a small gap between the subbase and the
cover appears.

4. Remove the screwdriver and pull the cover straight
down until it meets a stop.

5. Pull the cover straight off the subbase.

C7232A Cover Replacement

1. Feed the wires through the opening in the subbase.

2. Place the cover, with a small gap at the top, flat on top

of the subbase.

3. When the cover rests flat on the subbase, slide it
straight up until it latches in place.

B

UTTON HEAD

CAUTION

Equipment Damage Hazard.
Electrostatic discharge can short equipment
circuitry.

Ensure that you are properly grounded before
handling the unit.

OCKET CAP
CREW

A

M17541

Fig. 3. C7232A cover removal.

C

ALLEN TOO

3 63-2571—4