Semiconductor Gas Sensor Refrigerant (R22) Sensor - SP-41-00

Semiconductor Gas Sensor Refrigerant (R22) Sensor SP-41-00 Description:

The SP-41 is a SnO2 semiconductor gas sensor with high sensitivity to HCFCs such as Freon R22, and reduced sensitivity to other gases such as alcohol.

Semiconductor Gas Sensor Refrigerant (R22) Sensor SP-41-00 Parameters:

Structure

The gas sensing semiconductor material is of bead type, with heating coil and electrode wires embedded in the element. The sensing element is mounted in a metal package made of double stainless steel mesh that allows air circulation. This mesh has explosion-proof characteristics (Fig1).

Operating Conditions

Fig2 shows the standard circuit for this product. The change in sensor resistance (Rs) causes a change in the voltage across the load resistor (RL). For optimal performance and parameters, the values of heating voltage (VH), circuit voltage (Vc), and load resistance (RL) must be within the standard operating conditions specified in the table on the next page.

Sensitivity Characteristics

Fig3 shows the sensitivity characteristic curve of SP-41 (typical data). The sensitivity parameter of a gas sensor is the relationship between sensor resistance and gas concentration. Based on logarithmic function, as sensor resistance decreases, the measured gas concentration increases. The sensitivity parameters of SP-41 are detailed by the following parameters.

--Sensor resistance: In air containing 1000 ppm R22

--Sensor resistance change rate: In air containing 1000 ppm to 3000 ppm R22

Specific Parameters

A. Standard Operating Conditions

Symbol	Parameter	Specification	Condition
VH	Heating Voltage	5V ±4%	AC or DC
VC	Circuit Voltage	5V ±4%	AC or DC
RL	Load Resistance	Variable	PS<15mW
RH	Heater Resistance	40Ω ± 2Ω	Room Temperature
PH	Heater Power Consumption	400mW	PH = VH2 / RH (typical)
PS	Sensor Power Consumption	Less than 15mW	PS=(VC - VRL)2/RS

B. Environmental Conditions

Symbol	Parameter	Specification	Condition
Tao	Operating Temperature	-10~60°C	Recommended Range
Tas	Storage Temperature	-20~70°C
RH	Relative Humidity	<95%RH
（O2）	Oxygen Concentration	21% ± 1% (standard condition)	Minimum: >18%
		Sensitivity parameters are affected by changes in oxygen concentration.

C. Sensitivity Parameters

Model	SP-41-00
Symbol	Parameter	Specification	Condition
RS	Sensor Resistance	1kΩ~10kΩ	In air with 1000 ppm R22
β	Sensitivity Slope	0.25~0.55	RS in air with 3000 ppm R22 / RS in air with 1000 ppm R22
Standard test conditions: Temperature: 20 °C ± 2 °C, VC: 10.0 V ± 1% Humidity: 65% ± 5%, VH: 5 V ± 1% (In clean air), RL: 10KΩ ± 5% Preheating time: more than 96 hours

D. Mechanical Structure Parameters

Item	Condition	Specification
Vibration	Frequency: 100 cpm Vertical amplitude: 4mm Duration: 1 hour	Should meet specifications in sensitivity parameters
Shock	Acceleration: 100G Number of impacts: 5 times

E. Component Materials

No.	Part	Material
	Sensing Element	SnO2
	Substrate	Al2O3
1	Wire	Au-Pd-Mo
2	Heater	RuO2
3	Electrode	Au
4	Plastic Housing	Nylon 46 (UL94HB)
5	Plastic Substrate	Nylon 66 (UL94HB)
6	Stainless Steel Mesh	SUS316 (100 mesh, double layer)
7	Heater/Electrode Pins	Nickel

Volume