Relative Humidity
DISPLAYS
A CI
Product Data
A/RH Series
Relative Humidity Transmitters
“First in Sensor Quality”
The A/RH Series Relative Humidity transmitters, convert a resistance
change to a linear 4 to 20 mA, 0 to 5 VDC, or 0 to 10 VDC output. The
current signal may be transmitted over long distances on twisted-pair wire
and will not be affected by the lead wire resistance or electrical noise.
Accuracy is maintained over the entire operating range, using a thermistor
for temperature compensation.
All A/RH Series transmitters have a limited 2 year warranty.
1%, 2%, 3%, and 5%
Accuracies
Low Drift
Highly Repeatable
Calibration Certificates
Available
Applications:
Building Automation Systems
PRESSURE
Each A/RH Series humidity transmitter is calibrated using a NIST
Traceable Temperature /Humidity Chamber. Both three and five point
calibration certificates are avalable for 1% and 2% RH accuracies but
they must be ordered separately.
Field selectable output signals
RELATIVE HUMIDITY
The Advanced Ceramic Technology design overcomes the limitations of
other resistance-based humidity sensors that utilize water-soluble polymer
coatings. The Advanced Ceramic Technology enables these sensors to
recover fully from condensation. This also allows the sensor to maintain
its accuracy over a longer period of time. Despite its high accuracy, the
Advanced Ceramic Technology sensor and related circuitry is economical.
Attributes:
Single point Field Calibration
TEMPERATURE
Product Description
Light Industrial
Pharmaceutical
Supply Voltage
Accuracy @ 77oF
Wiring Diagrams available at www.workaci.com/instructions.htm
Data acquisition
OEM
Automation Components, Inc.
2305 Pleasant View Rd.
Middleton, WI 53562
PH: (608) 831-2585
FAX: (608) 831-7407
C0000105 rev 3.pdf
RH-1
ACCESSORIES
Long Term Stability
Hysteresis
Repeatablity
Sensitivity
Response Time
Operating Temperature Range
Operating Humidity Range
Saturation Response Time
Humidity Chambers
AIR QUALITY
Power Consumption
RH Measurement Range
RH Output
250 Ohm Load: +15 to 36 VDC / 21.6-26.4 VAC
0-5VDC: +15-36 VDC / 21.6-26.4 VAC
500 Ohm Load: +18 to 36 VDC / 21.6-26.4 VAC
0-10VDC: +18-36 VDC / 21.6-26.4 VAC
1 VA max.
0 to 100%
2-wire, 4 to 20mA (Factory Standard)
3-wire, 0-5, 0-10 VDC or 4 to 20mA
+/- 1% over 20% span (between 20 to 90%)
+/- 2%, 3%, or 5% from 20 to 95%
Less than 2% drift / 5 years
Less than 0.4% RH
0.5% RH
0.1 % RH
110 seconds for 63% Step
-10 to 122oF (-23.3 to 50oC)
0 to 95 % RH non-condensing
10 minutes for 63% Step
CURRENT
Product Specifications
DISPLAYS
Dimensions
Room
Outside
TEMPERATURE
2.75"
(70 mm)
1.15"
(29 mm)
3.60"
(91 mm)
0.18"
(5 mm)
O.D. Ref.
3.84"
(98 mm)
4.51"
(115 mm)
RELATIVE HUMIDITY
(4) PG11 1/2"
(127 mm) NPT
Knockouts
Mounting Hole
Separation:
2.69" (68 mm)
2.25"
(57 mm)
Duct
Stainless Plate
PRESSURE
0.65" dia.
(17 mm)
0.75" dia.
(19 mm)
7.15"
(182 mm)
CURRENT
2.25"
(57 mm)
AIR QUALITY
Ordering Information
Accuracy
[
4.50"
(114 mm)
1.00"
(25 mm)
60 Micron S.S.
Sintered
Filter
0.75"
(19 mm)
A/
Plastic
Washer
Range if 1%
]
-[
]
2.75"
(70 mm)
Configuration
-[
]
ACCESSORIES
(R) Room
RH1 (+/- 1%)
Please Specify
(D) Duct
RH2 (+/- 2%)
a 20% Span
(O) Outdoor Air
RH3 (+/- 3%)
(i.e. 40-60%)
RH5 (+/- 5%)
(SP) Stainless Plate
3 PT NIST Certificate (3 point Calibration Certificate @ 20, 50 and 80% RH)
5 PT NIST Certificate (5 point Calibration Certificate w/standard points choosen by ACI)
Example: A/RH3-R
or
A/RH5-D
or
A/RH2-O or A/RH1-(40 to 60%)-SP
2305 Pleasant View Rd. Middleton Industrial Park Middleton, WI 53562
PH: (608) 831-2585 FAX: (608) 831-7407
RH-2
0.75" dia.
(19 mm)
ACI
Installation and Operation Instructions
ACI/RH Room Series
Automation Components, Inc.
Please Read Instruction Carefully Before Installation!
The ACI/RH Room Series transmitters are a universal Relative Humidity transmitter that can be powered with either a
+15 to 36 VDC or 24 VAC supply voltage. The ACI/RH uses a half-wave bridge rectifier to convert the AC power to a
useable DC voltage. Caution: When using a 24 VAC transformer, ACI recommends that you use an isolated
transformer. If sharing the transformer with your controller, valve, actuator, or any other device, be sure to connect
all of the devices with the proper polarity, since most controllers are earth grounded. Failure to do so may result in
damage to the ACI/RH, your controller, or any other devices that are attached due to a ground loop problem.
The ACI/RH Room transmitters are designed with a field selectable 4-20 mA, 0-5 VDC, or 0-10 VDC output signal that
is equivalent to 0 to 100% RH. Unless specified upon ordering, all units are shipped from the factory to accept DC
power with a 2-wire, 4-20 mA loop-powered output. Caution: When changing the Output Selection Switch (SW3)
make sure that the power supply is turned off before making any changes. Failure to do this may cause damage to the
unit.
RH Wiring Diagram
ACI recommends that all ACI/RH 4-20 mA Room relative humidity transmitters be wired with a 16 to 22 AWG 2-wire
twisted pair or shielded cable for best results. All ACI/RH Room voltage output transmitters should use a 3-wire 16 to 22
AWG shielded cable. Note: When using a shielded cable, be sure to connect only (1) end of the shield to ground at
the controller. Connecting both ends of the shield to ground may cause a ground loop.
Zero Adjust
Potentiometer
Output Selection Switches (SW3)
AC/DC Power
0-5 VDC Out
4
3
2
AC Power
4-20mA Out
1
4
3
2
SW3
1
Span Adjust
Potentiometer
1
2
3
4
ON
ON
ON
AC/DC Power
0-10 VDC
4
3
2
1
ON
2
4
3
Wire Access Hole
1
DC Power
4-20mA Out
Io Vin Gnd Vo
ON
Figure # 2
Test and Calibration Switch Settings (SW2)
Normal Operating Condition
4
5
1
6
ON
4
5
6
ON
4
5
6
1
2
3
4
5
6
ON
ON
Decrement RH Output
3
4
5
6
1
ON
2
3
4
5
ON
2
4
5
6
6
ON
1
3
3
4
5
6
Figure # 3
2
Reset to Original Calibration
Figure # 1
2305 Pleasant View Rd. Middleton Industrial Park Middleton, WI 53562
PH: (608) 831-2585 FAX (608) 831-7407
File Name: I0000144 Rev1
3
2
Relative Humidity Temperature Sensor
Temperature Sensor (Combination Unit)
2
1
ON
100% RH Output
1
3
S2
Increment RH Output
1
2
50% RH Output
S1
3
SW2
2
Relative Humidity Sensor
1
0% RH Output
+24 VAC Input / 4 to 20mA Output
+15 to 36 VDC Input / 4 to 20mA Output
Supply Ground / Common
Span
+24 VAC Supply Voltage
Span
Zero
4 to 20mA Output
SW3
3
SW3
2
Zero
4 to 20mA Output
1
+15 to 36 VDC Supply Voltage
4
1
ON
2
3
4
ON
Io Vin Gnd Vo
Io Vin Gnd Vo
SW2
1
2
SW2
3
4
5
6
1
ON
S2
2
3
4
5
6
ON
S1
S2
S1
+24 VAC Input / 0 to 10 VDC Output
+15 to 36 VDC Input / 0 to 5 VDC Output
0 to 5 VDC Output
0 to 10 VDC Output
Supply Ground / Common
Supply Ground / Common
Span
Span
Zero
+24 VAC Supply Voltage
SW3
2
3
4
SW3
1
Zero
1
ON
+15 to 36 VDC Supply Voltage
2
3
4
ON
Io Vin Gnd Vo
Io Vin Gnd Vo
SW2
2
3
4
5
6
1
ON
2
3
4
5
6
ON
S1
1
SW2
S2
S1
S2
Figure # 4
RH Test and Calibration Dip Switch Settings (See Figure #3)
Note: Do not adjust these switches unless you are using them to troubleshoot or recalibrate the sensor. Dipswitch #3
should always be left in the ON position. Failure to do so will not allow the RH transmitter to read the sensor (The
output will always remain the same).
0% RH Output - Transmitter always outputs a signal of 4 mA or 0 VDC. Sensor doesn’t affect the transmitter
output. (For Trouble Shooting Purposes Only)
50% RH Output - Transmitter always outputs a signal of 12 mA, 2.5 VDC, or 5 VDC. Sensor doesn’t affect the
transmitter output. (For Trouble Shooting Purposes Only)
100% RH Output - Transmitter always outputs a signal of 20 mA, 5 VDC, or 10 VDC. Sensor doesn’t affect the
transmitter output. (For Trouble Shooting Purposes Only)
Normal Operating Condition - The DIP switch must be set in this position for the RH signal to change, due to the
actual measurement of the Relative Humidity by the humidity sensor.
Increment RH Output - This DIP switch will allow you to calibrate the sensor through the software. The switch
must be toggled from the Off to the On position and then returned to the Off position for an
increase of 0.5% RH. This means that if your humidity has drifted 1% over a certain time
period, you will be able to toggle the Increment RH Output switch (2) times in order to
slide the whole curve upward 1%. Note: This is only a single point calibration, and is not
2305 Pleasant View Rd. Middleton Industrial Park Middleton, WI 53562
PH: (608) 831-2585 FAX (608) 831-7407
File Name: I0000144 Rev1
recommended for critical applications. Please contact the factory before doing any
field calibration.
Decrement RH Output - This DIP switch will allow you to calibrate the sensor through the software. The switch
must be toggled from the Off to the On position and then returned to the Off position for a
decrease of 0.5% RH. This means that if your humidity has drifted 1% over a certain time
period, you will be able to toggle the Decrement RH Output switch 2 times in order to
slide the whole curve downward. Note: This is only a single point calibration, and is not
recommended for critical applications. Please contact the factory before doing any
field calibration.
Reset to Original Calibration - Both the Increment and the Decrement DIP switches should be turned on for a
minimum of 5 seconds before turning them both off again. This will allow you to reset
the transmitter back to the original factory calibration.
Temperature Sensor Wiring Diagram (For RH/Temperature Combination Units only)
Zero Adjust
Potentiometer
Span Adjust
Potentiometer
SW3
1
2
4
3
ON
Io Vin Gnd Vo
O/R
"After Hours" N/O Override ( Dry Contact Closure)
"After Hours" N/O Override (Dry Contact Closure)
Wire Access Hole
+ T -
Setpt
J2
"After Hours" N/O Override Pushbutton
Adjustable Setpoint Actuator
(+) Temperature Sensor / Override (Short Sensor)
Output to Building Automation /DDC System
(-) Temperature Sensor / Override (Short Sensor)
Output to Building Automation / DDC System
Adjustable Setpoint Output to Controller
Adjustable Setpoint Output to Controller
J3
Override Jumper Settings (J2)
Override Shorts
Sensor
SW2
1
2
3
4
5
6
J2
Separate Input
(Dry Contact)
J2
ON
Relative Humidity Sensor
S1
S2
Relative Humidity Temperature Sensor
Temperature Sensor (Combination Unit)
Note: When using an AD592 or LM334 Temp. sensor with a current (uA)
output, the (+) T terminal should be used for a +5 to 30VDC
supply voltage and the (-) is the current output to the Building
Automation or DDC System.
Figure # 6
Setpoint Jumper Settings (J3)
In Series with
Sensor
J3
Separate Input
J3
Figure # 7
Figure # 5
Space Mount:
The RH transmitter should be placed away from areas of excessive moisture, corrosive fumes, vibration, or extremely
high temperatures. The base of the housing was designed to mount over a standard 2” X 4” single gang junction box or
flush to the wall. All of the RH sensors have a +/- 3% interchangeability. It is recommended to do a single point
calibration for a much higher accuracy.
1.
2.
3.
4.
5.
6.
Mount the unit on an indoor wall, approximately 4 to 6 feet above the floor.
Make sure that the unit receives adequate airflow.
Connect the wires to the corresponding terminal blocks as shown in Figure #4 and Figure #5.
Now make sure that all of the dip switches are properly set before initially powering the unit.
Now snap the cover back into position.
Finally turn out the (2) 1/16”Allen screws at the bottom of the enclosure until the cover cannot be removed.
2305 Pleasant View Rd. Middleton Industrial Park Middleton, WI 53562
PH: (608) 831-2585 FAX (608) 831-7407
File Name: I0000144 Rev1
Troubleshooting
No reading
1. Check that you have the correct supply voltage at the power terminal blocks.
2. Check wiring configuration and all DIP switch settings are as in Figure #2 and
Figure #3.
3. Verify that the terminal screws are all connected tightly and that all of the wires
are
firmly in place.
Erratic readings
Inaccurate readings
1. Verify that all of the wires are terminated properly.
2. Make sure that there is no condensation on the board.
3. Check that the input power is clean. In areas of high RF interference or noise,
shielded cable may be necessary to stabilize signal.
1. If you suspect that the transmitter is not reading within the specified tolerance,
please contact the factory for further assistance.
RH Conversion Formulas
To convert transmitter output signal to %RH.
4-20mA to %RH
Example: 12mA transmitter signal output
(12mA-4mA)/ 0.16 = 50% RH
0-5 VDC to %RH
Example: 2 VDC transmitter signal output
2 VDC/0.05 = 40% RH
0-10 VDC to %RH
Example: 8 VDC transmitter signal output
8 VDC/0.10 = 80% RH
2305 Pleasant View Rd. Middleton Industrial Park Middleton, WI 53562
PH: (608) 831-2585 FAX (608) 831-7407
File Name: I0000144 Rev1