PTC Thermistors Glossary and Definition
PTC Thermistor Zero Power Resistance
DC resistance value of the thermistor measured under 25C by adopting sufficiently low power consumption.
PTC Thermistors Maximum Operating Voltage (Vmax)
The maximum rated voltage the PTC thermistor can continuously endure at 25C.
PTC Thermistors Maximum Inrush Current
The maximum current (effective value) through the PTC thermistor under max. rated voltage. Exceeding this current may result in damage to the PTC components.
PTC Thermistor Switch Temperature
The temperature at which the resistance value of the PTC thermistor increases to twice the zero-power resistance, also called PTC Thermistor Curie temperature, or PTC Thermistor Reference temperatureŁ¬or PTC Thermistor transition temperature .
PTC Thermistor Non-trip Current
Also called PTC Thermistor Rated Current or Holding Current, or Non-operating CurrentŁ¬ means the current at which PTC thermistor resistance does not exceed the specified value for designated time and temperature conditions.
PTC Thermistor Trip Current
Initial current which causes PTC thermistor resistance to leap, also called PTC Thermistor Operating Current.
PTC Thermistors Temperature Coefficient of Resistance
PTC thermistor temperature coefficient is calculated from the linear range at the steepest portion of resistance (Tb-Tp) . aT=(LnRp-LnRb) ˇ¤100/(Tp-Tb) (%/C)
PTC Thermistors Dissipation Factor
The ratio power dissipation change to temperature change of PTC thermistor (in mw/C). =P/(T-Tr) Where P = dissipation power T =thermistor body temperature Tr =room temperature
PTC Thermistors Restore time
Time for restore of PTC thermistor resistance to twice the zero-power resistance after power is switched off.
PTC Thermistor Temperature range under maximum voltage
Operating ambient temperature range that PTC thermistor can continuously operate under maximum voltage.
PTC Thermistor Breakdown voltage
The maximum voltage that PTC thermistor can bear under stipulated time and temperature. PTC thermistor will breakdown exceeding this voltage.
PTC Thermistor Residual current (Ir)
Current under heat balance state, after PTC thermistor resistance increases sharply, under maximum operating voltage.
T1,T2 corresponding to R1,R2. 10C, 25C higher than curie temperature separately.
PTC Thermistor Temperature at minimum resistance
Temperature corresponding to minimum resistance.
PTC Thermistor Upper category temperature
Maximum ambient temperature that PTC thermistor can operate continuously.
PTC Thermistor Low Category Temperature
Minimum ambient temperature that that PTC thermistor can operate continuously.
Thermistors that satisfy stipulated insulation resistance and voltage test requirement.
Thermistor that do not require insulation voltage and insulation resistance test.
PTC Thermistor Initial Current
The current that appears instantaneously in circuit switch starting to closing.
PTC Thermistor Peak Current
Peak-peak value of initial current.