Purchase of pressure sensitive resistance test method and pressure sensitive resistance tester
Measurement method of pressure sensitive resistance:
The electrical characteristics (such as maximum working voltage, breakdown voltage, rated power, maximum limit voltage, maximum pulse current, energy tolerance, varistor voltage temperature coefficient, the maximum static capacitance, loss tangent, leakage current, voltage etc.)
Mechanical properties (such as tensile strength, vibration resistance, welding resistance, heat resistance, etc.)
Environmental characteristics (such as: high temperature storage, low temperature storage, humidity resistance, temperature cycling characteristics, high temperature load characteristics, Climatic sequence, pulse life, etc.)
Matters needing attention:
(1) the maximum continuous operating voltage of the selected pressure sensitive resistance, the maximum amount of change for the supply voltage must be a margin.
(2) the application occasions (such as the voltage applied to the simulation test), please do not exceed the rated pulse power of the pressure sensitive resistance.
(3) when using the pressure sensitive resistance, please select the type of the type of pressure - sensitive resistance which is recommended in the schedule.
When using the A. circuit, due to unbalanced load, short-circuit accident, capacitive load of the switch open and close, etc., will lead to a transient increase in the supply voltage, so even for AC100V, AC120V,
Between the B. circuit and the earth, the ground voltage will rise due to the single line grounding fault.
C. the temperature fuse: the pressure sensitive resistance and the temperature fuse connection situation, please as far as possible the fuse and the pressure sensitive resistance has the good heat contact.
Non destructive testing of pressure sensitive resistance:
Preset graphic instrument, scanning the collector output knob: 0 or counterclockwise to the end, scanning mode: AC or NPN+ collector series resistance: 50K-200K or more, the horizontal and vertical deflection factor switch: choosing the proper spot position: center or left foot scale scale origin. Insert the pressure sensitive resistor into the "C" and "E" socket hole, and choose the right and left switch position according to the position of the pressure sensitive resistor. The adjustment of the collector scanning output knob, the nominal value is close to the scanning voltage sensitive resistor, physical breakdown (current surge voltage and slow change), in the current interest in the reading level calculated voltage value (deflection * horizontal deflection factor).
After measuring, quickly adjust the output knob to the 0 position. Note: this test is not destructive, as long as it does not exceed the rated power consumption of the pressure sensitive resistance. For reference.
Three parameter instrument for measuring the pressure of the pressure sensitive resistance:
The test instrument varistor three parameter meter, that is to say, with the effect of varistors three key parameters: first the voltage, current and power.
Can do a double voltage rectifier (note that the current is not too big, otherwise it will burn out, Ya Min) the voltage than Ya Min resistance nominal value, then the voltage doubling rectifier with Ya Min in his legs, and then use the multimeter to measure the voltage value of the feet, Ya Min is not only the actual voltage value, if there is a pressure meter will be more convenient, if the transistor tester will be more accurate.