Resistive RH Sensor



  • Wide range of applications
  • Excellent Reliability
  • Water Resistance
  • RoHS Compliant
  • Interchangeability


Energy Saving HVAC Control

Air Conditioning, Refrigeration, IAQ monitoring, Vent Fans, Home Appliances, Humi/Dehumidifiers

Process Control & Instrumentations

Medical Instruments, Handheld Devices, Weather Stations,Food Processing, Printers, RFIDs

Product Summary

Industrial grade resistance type humidity sensor; SYH-2R offers cost effective and convenient humidity measurement.

While maintaining the attractive features such as no-calibration requirement and high interchangeability of resistive type humidity sensor: SYH-1, SYH-2R widens the scope of applications to home appliances, HVAC, and automotive.

Coated with patented polymer, SYH-2R can be used in demanding environments (-20°C~85°C) with frequent condensing and chemical vapors.

SYH-2R can be directly connected to µ-com with ADC or RFC converting resistance changes to either voltage or frequency. It can also be modularized to voltage output with oscillator.

Electrical Characteristics

Min Spec max
Rated voltage (VRMS) 1 3.536
Rated power (㎽) 0.26
Standard characteristics (㏀) 33
Operating temperature (℃) -20 85
Operating humidity (%RH) 10 95
Operating Frequency (㎑) 0.1 10
Storage temperature (℃) -40 85
Storage humidity (%RH) 95
Accuracy (%RH) -3 3
Hysteresis (%RH) -2 2
Response time (T80, sec.) 45
Temperature coefficient (%RH/℃) -0.5


Test Condition
HTS 85℃, 1000hrs
LTS -30℃, 1000hrs
THB 85℃, 85%RH,1000hrs, Bias
HC 30↔90%RH, 25℃, 100 times
TC -30↔85℃, 100 times
Organic solvent Benzene, Xylene, Toluene, 300hrs
M/C(drop) 100cm drop, 3 times
Vibration X-Y-Z, 10~55㎐, 2hrs
Soldering heat 260±5℃, 3 sec.
Tensile 500g(4.9N), 10 sec.

Resistive RH Sensor Module



  • High Reliability & Excellent Life span
  • Outstanding Durability
  • Wide Operating Temp. Range
  • Interchangeability
  • Availability of Customized products


A resistive humidity sensor, SY-HS-25 Series, is composed of excellent durable resistive sensor and a thermistor for temperature compensation and offers cost competitiveness and convenience for humidity measurement.
This module uses specially consolidated polymer and is designed for industrial environment that includes both temperature environment (-20~85℃) and humidity environment with dew condensation and gases. In addition, it can be used without calibration so that replacement of sensor is easy and convenient.

Relative Humidity (%RH)

Humidity Characteristics Symbol Min. Typ. Max. Unit
Standard Characteristic
(at 25℃, 60%RH,1Vrms, 1 kHz)
33 KΩ
Operating Frequency Range 0.1 10 kHz
Relative Humidity Accuracy
(at 25℃, 60%RH)
±3 %RH
Humidity Hysteresis
(at 25℃, 40⇔80%RH)
±2 %RH
Response Time (40⇔80%RH)) 60 sec
Temperature Coefficient Tcc 0.5 %RH/℃
Temperature Coefficient Tcc -0.05 %RH/℃

Temperature (℃)

Temperature Characteristics Symbol Min. Typ. Max. Unit
Temperature Measuring Range Ta -40 120
Nominal Resistance @25℃ R 47.5 50 52.5
Beat Value : B25/85 B 4500 K
Normal Resistance Tolerance @℃ T ±5 %
B Value Tolerance B ±3 %

Dew Sensor



  • Small, Light
  • High sensitivity under high-humidity condition
  • Switching function
  • Quick response
  • High reliability and stability


SY-DS-1 Series, dew sensor, is a resistive type sensor which detects condensation risk in advance. The sensor only responds to high humidity environment regardless of temperature environment, and it is a switch-type sensor whose impedance value changes abruptly in a high humidity environment.
It has an excellent reaction rate, no temperature dependence, and is water resistant, easy to implement and simple to use.
Two types of the product are available upon request – 1) Lead pin type 2) Harness type

Sensor Performance

Rated voltage DC AC 0.8V Max.
temperature range
0℃ ~ ±60℃
Humidity range
0%RH ~ 100%RH
Condition range
-20℃ ~ 85℃
a) 10㏀ Max. at 80%RH
b) 100㏀ Max. at 94%RH
C) 200㏀ Max. at 98%RH