Calibration
Your transmitter has been factory calibrated to meet or exceed the
specifications outlined in this manual. To maintain original
specifications it is generally recommended that your transmitter be re-
calibrated on an annual basis depending on operating conditions.
Relative Humidity Calibration Procedure
Recommended equipment:
Humidity Generator/Calibrator Kit, OMEGA
®
Model No.: RHCL-KIT
Handheld Digital Multimeter, OMEGA
®
Model No.: HHM29
Note: Do not make adjustments to potentiometer “P3”, this
is a factory setting and is not field adjustable. If “P3” is
disturbed the transmitter will need to be returned to the
factory for service.
1. Remove enclosure cover
2. Connect transmitter as shown in figure below.
3. Apply power to transmitter and allow to warm up for 15 min.
4. Place sensor in a 20% RH environment and allow to stabilize for 20 min.
5. Adjust potentiometer “P1” for a output reading of 7.2 mA
6. Place sensor in a 80% RH environment and allow to stabilize for 20 min.
7. Adjust potentiometer "P2" for an output reading of 16.8 mA
8. Repeat steps 4, 5, 6, 7 as necessary until proper readings are maintained.
9. Calibration complete.
Figure 4: Relative Humidity Calibration Procedure
N O T E
EWS-RH
Relative Humidity/Temperature Transmitter
6
MULTIMETER
POWER SUPPLY
1
6
+
+
–
–
5
4
3
2
1 6 . 8 0 m A
P 1
P 2
