Honeywell H7625B Duct-Mount and Outdoor-Mount Humidity Instruction Manual
- June 4, 2024
- Honeywell
Table of Contents
H7625B, H7626B, H7635B,C
H7636B, H7655B, H7656B
DUCT-MOUNT AND OUTDOOR-MOUNT HUMIDITY/
TEMPERATURE SENSORS
INSTALLATION INSTRUCTIONS
APPLICATION
The H76XXB Duct-Mount and H76XXC Outdoor-Mount Humidity/Temperature Sensors
are universal Relative Humidity transmitters that can be powered with either a
+18 to 40 Vdc or 24 Vac supply. The devices are half-wave rectified. The
transmitter also includes either a 20K ohm NTC thermistor or a 1K platinum PTC
(compatible with the T775) for optional temperature use.
The humidity sensors are designed with a field selectable 4 to 20 mA, 0 to 5
Vdc, or 0 to 10 Vdc output signal equivalent to 0 to 100% RH. All units are
shipped from the factory with a default setting to accept AC power with three-
wire, 0 to 10 Vdc output.
INSTALLATION
When Installing this Product…
- Read these instructions carefully. Failure to follow them could damage the product or cause a hazardous condition.
- Check ratings given in instructions and on the product to ensure the product is suitable for your application.
- The installer must be a trained, experienced service technician.
- After installation is complete, check out product operation as provided in these instructions.
CAUTION
Electrical Shock or Equipment Damage Hazard.
Can shock individuals or short equipment circuitry.
Disconnect the power supply before installation.
CAUTION
Equipment Damage Hazard.
Improper wiring can damage the sensor beyond repair.
Follow the wiring instructions carefully.
Mounting
The method of mounting depends on the particular sensor application. The
following procedures include outdoor and duct applications. Also, refer to the
instructions for the electronic control.
Duct mounting Configuration
The H7625B, H7626B, H7635B, H7636B, H7655B, and H7656B can be mounted in a
duct to sense humidity and temperature.
IMPORTANT
Select a location to expose the sensor to average duct humidity and
temperature. Avoid locations where stratification can cause sensing errors.
NOTES:
- Knockouts allow 1/2 in. conduit connection. To avoid damaging the board during installation, the cover can be detached completely:
- Carefully remove the wire plug from the board.
- Set the cover aside.
- Drill a 3/4” diameter hole in the duct where the transmitter is to be mounted.
- Insert the stainless steel probe into the hole until the foam is in direct contact with the duct.
- Attach the transmitter to the duct using the supplied #8 X 3/4” self-tapping screws.
- Remove the cover and install your conduit connector or watertight fitting. The outer ring is used when using a 1/2” NPT conduit fitting.
- After wiring the unit, place the cover back on and gently turn it until it is tight.
Outdoor Mounting Configuration
The H7635C senses outdoor air humidity and temperature. Mount this control
where it can sense average outdoor air humidity and temperature. Normally, the
north side of a building provides a suitable location.
NOTES:
- H7635C is weatherproof for outdoor use. Knockouts allow 1/2 in. conduit connection.
- To avoid damaging the board during installation, the cover can be detached completely:
- Carefully remove the wire plug from the board.
- Set the cover aside.
The transmitter should be mounted under an eave, shield, or in an area out of the elements or direct sunlight. The aluminum tube should point down when mounting the outside transmitter. Refer to Figure 1 for the proper mounting position.
- Place the unit where it is to be mounted with the cover facing out.
- Attach the unit with the supplied #8 X 3/4” self-tapping screws.
- Remove the cover and install your conduit connector, watertight fitting, or 1/2” vent plug. The outer ring is used when using a 1/2” NPT conduit fitting.
- After wiring the unit, place the cover back on and turn it until it is tight.
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Output Settings
The humidity output signal can be adjusted for 0-5Vdc, 010 Vdc, or 4-20 mA
using the switch block. Switches 6, 7, and 8 are used to set the output.
NOTE: Refer to Fig. 2 for switch settings.
Table 1. Controller Compatibility and Output Settings.
| Controller | Required Sensor Output Setting | inspect Setting |
|---|
W7750, W7760,
W7761| 4-20 mA| C7600C
W7750B,C
W7760C, W7753,
W7760| 0-10 Vdc (default)| H7621/31
T7350, XL50,
XL100, XL500 XF
Modules, XFL| 0-10 Vdc (default)| n/a
Non-Honeywell| 0-5 Vdc| n/a
REVERSE ACTING OUTPUT
The output can be changed to reverse acting mode. The output range stays the
same but the corresponding RH value is the opposite.
Example:
Direct Acting (DA) (Default)
0-10V output mode
0V = 0% RH and 10V = 100% RH
Reverse Acting (RA)
0-10V output mode,
0V = 100% and 10V = 0%
To change the transmitter to reverse acting or back to direct acting, set
switch 4 ON to put the unit in the setup ode. After switch 4 is on, switch 2
will put the unit in direct/reverse acting mode. When switch 2 is set to ON,
the output can be used to show if the unit is in direct or reverse acting
mode. For direct acting the output will be 1V for 0-5V, 2V for 0-10V, and
7.2mA for 4-20mA. For reverse acting the output will be 4V for 0-5V, 8V for
0-10V,
and 16.8mA for 4-20mA.
With switches 2 and 4 ON, each time switch 5 is set to ON the output will
change to reverse acting or direct acting.
To reset the unit to the default setting, toggle both switches 5 and 6 ON and
then OFF while both switches 2 and 4 are ON.
When all calibration is completed, remember to place the switches back into
the positions that correspond to the output needed as shown in Figure 3.
WIRING
A 16 to 22 AWG shielded cable is recommended for all transmitters. Twisted
pairs may be used for 2-wire current output transmitters. the connections to
the temperature sensor should be made with wire nuts or crimp-style
connectors. Refer to Figure 3 for wiring diagrams.
CAUTION
Never connect or disconnect wiring with power applied.
Fig. 3. Wiring Diagrams
CAUTION
It is recommended that you use an isolated UL-listed class 2 transformer when
powering the unit with 24 VAC. Failure to wire the devices with the correct
polarity when sharing transformers may result in damage to any device powered
by the shared transformer.
IMPORTANT
When using shielded cable, ground the shield only at the controller end (see
Fig. 4). Grounding both ends can cause a ground loop.
Fig. 4. Typical wiring diagram
for a transducer with two-wire mA output with external DC power supply.
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
ENSURE THE TRANSFORMER IS SIZED TO HANDLE THE LOAD.
HEAT/COOL SYSTEMS WITH ONE TRANSFORMER REQUIRE THE FACTORY-INSTALLED JUMPER.
USE ECONOMIZER INSTRUCTIONS FOR INSTALLATION DIRECTIONS.
HC AND HP PROVIDE 24 VAC TO THE HUMIDITY SENSOR.
Fig. 5. Humidity Sensor (0-10 Vdc output) wiring with T7350 (use with RH/Temperature combination T7350 units only).
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
TEMPERATURE SIGNAL CONNECTIONS ARE NOT POLARITY SENSITIVE.
Fig. 6. Typical wiring diagram for 5-wire temperature/humidity sensor with
Vdc output (used with the XL15A controller).
Fig. 7. Typical wiring diagram
for 5-wire temperature/humidity sensor with Vdc output (used with the Spyder
controller).
CHECKOUT
CAUTION
Equipment Damage Hazard. Can short electric circuitry.
- Never connect 120 Vac to the transducer.
- Connect only DC voltage to a transducer intended for DC supply.
NOTE: Use laboratory quality meters and gauges for applications requiring a high degree of accuracy.
- Verify that the transducer is mounted in the correct position.
- Verify the appropriate input signal and voltage supply.
- Verify the appropriate configuration range.
Converting Output Signal to Percent RH
4 to 20mA Signal
((mA signal) -4) / 0.16 = percent RH
Example: 12mA output signal
(12-4) / 0.16 = 50% RH
0 to 5 Vdc Signal
(VDC signal) / 0.05 = percent RH
Example: 1.25vdc output signal
1.25 / 0.05 = 25% RH
0 to 10 Vdc Signal
(VDC signal) / 0.10 = percent RH
Example: 7.50vdc output signal
7.50 / 0.10 = 75% RH
Table 2. Troubleshooting.
| Problem | Items to Check |
|---|---|
| No reading | • Verify the correct supply voltage at the power terminal blocks. |
| • Verify correct wiring configuration and DIP switch settings per Figures 2 |
and 3.
| • Verify that terminal screws are connected tightly with all wires firmly in
place.
Erratic readings| • Verify all wires are terminated properly.
| • Ensure that there is no condensation on the board.
| • Verify clean input power. In areas of high RF interference or noise, the
shielded cable can be necessary to stabilize the signal.
Inaccurate| • If you suspect that the transmitter is not reading within the
specified tolerance, please contact
readings| the factory for further assistance
APPENDIX
RH Test and Configuration DIP Switch Settings (Table 3)
IMPORTANT
- Only adjust these switches for troubleshooting or recalibrating the sensor. (Adjustment is not normally necessary.)
Test mode will make the transmitter output a fixed 0%, 50%, or 100% value. The
sensor will not affect the transmitter output. This is used for
troubleshooting or testing only.
Switches 1, 2, and 3 are used for test mode. The output will be a fixed 0%,
50%, or 100% signal that corresponds to the output selected with switches 6,
7, and 8. Refer to Figure 4 for switch settings.
Table 3. Test and Calibration Settings (8-Switch Block).
| Setting | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
|---|---|---|---|---|---|---|---|---|
| 4-20mA Output | _ | _ | _ | _ | _ | _ | _ | _ |
| 0-5 VDC Output | _ | _ | _ | _ | _ | On | On | _ |
| 0-10 VDC Output | _ | _ | _ | _ | _ | _ | On | On |
| 0% RH Output | On | _ | _ | _ | _ | _ | _ | _ |
| 50% RH Output | _ | On | _ | _ | _ | _ | _ | _ |
| 100% RH Output | _ | _ | On | _ | _ | _ | _ | _ |
| Increment RH Output | _ | _ | _ | On** | On | _ | _ | _ |
| Decrement RH Output | _ | _ | _ | On** | _ | On | _ | _ |
| Reset to Original Calibration | _ | _ | _ | On** | On | On | _ | _ |
| Reverse or Direct Acting | _ | On | _ | On** | On | _ | _ | _ |
| Reverse or Direct Acting Reset | _ | On | _ | On** | On | On | _ | _ |
- = Switch setting does not affect the output
** = This switch needs to be activated first
— = Indicates OFF
CALIBRATION
NOTE: This is only a single-point calibration. All transmitters are
factory calibrated to meet/exceed published specifications. Field adjustment
should not be necessary.
The dipswitch allows the user to calibrate the sensor through the software.
Setting switch 4 ON will put the transmitter into setup mode allowing the
increment and decrement to work. Once in setup mode, the output will change to
50% (2.5V for 0-5V, 5V for 0-10V, 12mA for 420mA). Each increment or decrement
step will cause the output to change by 0.1V for 0-5V, 0.2V for 0-10V, and
0.32mA for 4-20mA in setup mode. This can be used to show the user how far
offset the transmitter is. To see the starting point again set switch 1 ON.
This will show the 50% output again. When the unit is out of setup mode the
output will go back to RH output.
Increment RH Output
This will shift the RH output linearly up in 0.5% steps. Switch 4 must be set
to ON first. After switch 4 is on, each time switch 5 is set ON the RH output
will increase by 0.5%. The increase goes into effect each time switch 5 is set
to ON.
Decrement RH Output
This will shift the RH output linearly down in 0.5% steps. Switch 4 must be
set to ON first. After switch 4 is on, each time switch 6 is set ON the RH
output will decrease by
0.5%. The decrease goes into effect each time switch 6 is set to ON.
Reset RH Output
This will reset the RH output back to the original calibration. Switch 4 must
be set to ON first. After switch 4 is on, toggle switches 5 and 6 ON then OFF.
After 5 and 6 are OFF slide switch 4 OFF.
When all calibration is completed, remember to place the switches back into
the positions that correspond to the output needed as shown in Figure 3.
LonSpec™ is a trademark of Echelon® Corporation.
By using this Honeywell literature, you agree that Honeywell will have no
liability for any damages arising out of your use or modification to, the
literature. You will defend and
indemnify Honeywell, its affiliates, and subsidiaries, from and against any
liability, cost, or damages, including attorneys’ fees, arising out of, or
resulting from, any modification to the literature by you.
Automation and Control Solutions
Honeywell International Inc.
1985 Douglas Drive North
Golden Valley, MN 55422
Honeywell Limited-Honeywell Limitée
35 Dynamic Drive
Toronto, Ontario M1V 4Z9
customer.honeywell.com
® U.S. Registered Trademark
© 2010 Honeywell International Inc.
62-0330—01 E.K. Rev. 03-10
Printed in the U.S.A.
Documents / Resources
|
Honeywell H7625B Duct-Mount and Outdoor-Mount
Humidity
[pdf] Instruction Manual
H7625B, H7626B, H7635B-C, H7636B, H7655B, H7656B, H7625B Duct-Mount and
Outdoor-Mount Humidity, H7625B, Duct-Mount and Outdoor-Mount Humidity,
Outdoor-Mount Humidity, Humidity
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References
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