Rated zero power resistance PPTC thermistor resistance should be zero-power sub-file packed and marked in the outer range of resistance. Pressure, resistance to flow capacity test, each sample before their very poor resistance rate of change of δ | Ri after-Ri Previous / Ri ago - (Rj post-Rj ago) / Rj Previous | ≤ 100% 2, PTC effect That kind of material with a PTC (Positive Temperature Coefficient) effect, namely, positive temperature coefficient effect, refers only to the resistance of this material will increase with increasing temperature. If most of the metal material has a PTC effect. In these materials, PTC effect manifested as resistance increases linearly with increasing temperature, which is commonly referred to as a linear PTC effects. 3, non-linear PTC effects Through the phase change material will show a resistance along the narrow temperature range increased dramatically from a few dozen orders of magnitude of the phenomenon, that is, non-linear PTC effects. Considerable variety of types of conductive polymer Experience has shown this effect, such as the polymer PTC thermistor. These conductive polymers for the manufacture of over-current protection device is very useful. 4, the initial resistance Rmin Being installed to the circuit before the ambient temperature is 25 ℃ under the conditions of test, RF / WH series of polymer PTC thermistor resistance. 5, Rmax At room temperature, RF / WH Series polymer PTC thermistor action or reflow soldering to a circuit board installed in an hour after the maximum resistance value measured. 6, minimum resistance (Rmin) / Maximum resistance (Rmax) In the specified ambient temperature, for example: 25 ℃, installed to the circuit prior to a specific type of RF / WH Series polymer thermistor resistance will be within a range specified, namely, minimum (Rmin) and maximum (Rmax ) between the. This value is listed in the specifications book, the resistance of column. 7, to maintain current Ihold The maintenance of current is the RF / WH Series polymer PTC thermistor to maintain non-operating conditions may be adopted by the maximum current. A limited environmental conditions, the device can maintain an unlimited length of time, rather than state transition from a low resistance to high-impedance state. 8, operating current Itrip A limited environmental conditions, so that RF / WH Series polymer thermistor for a limited time, the smallest steady state current of the action. 9, maximum current Imax (resistance to current value) A limited state, RF / WH Series polymer PTC thermistor of the largest security action action current, that is, the value of the thermistor resistance to flow. Than this value, thermal resistance may be damaged and can not be restored. This value is listed in the specifications of the resistance to flow of the book value of a column. 10, leakage current Ires RF / WH Series polymer PTC thermistor locked in its high impedance state, the current through the thermistor. 11, the maximum working current / normal operating current Under normal operating conditions, the maximum current flowing through the circuit. Environmental work in the circuit's maximum temperature, used to protect the circuit RF / WH Series polymer PTC thermistor to maintain current general operating current than the large. 12, action RF / WH Series polymer PTC thermistor over-current occurs or in the ambient temperature increases from low resistance to high resistance process of change. 13, movement time Over-current occurs between the start of the thermistor time to complete the required action. For any particular RF / WH Series polymer PTC thermistor, the greater the current flowing through the circuit, or the working environment the higher the temperature, the shorter the time of their actions. 14, Vmax the maximum voltage (pressure value) Under limited circumstances, RF / WH Series polymer PTC thermistor maneuvers, can safely withstand a maximum voltage. Namely, the value of the thermistor voltage. Than this value, thermal resistance may be breakdown, can not be restored. This value is usually listed in the specifications book, the value of a column pressure. 15, maximum working voltage In the normal operation state, across the RF / WH Series polymer PTC thermistor of the maximum voltage across. In many circuits, the equivalent circuit power supply voltage. 16, conductive polymer In this case by the conductive particles (carbon black, carbon fiber, metal powder, metal oxides, etc.) filled with insulating polymer materials (polyolefin, epoxy resins, etc.) obtained conductive composite material. 17, ambient temperature In conjunction with a thermistor or a thermistor circuit components around the still air temperature. 18, the working temperature range P elements can safely work in an environment temperature range. 19, maximum operating ambient temperature Components can be expected to the maximum safe working environment temperature. 20, the power depletion RF / WH Series polymer PTC thermistor action after the consumption of power flowing through the thermistor by calculating the leakage current and the voltage across the thermal resistance of the product to be. 21, high temperature, high humidity aging At room temperature, the measurement of RF / WH Series polymer PTC thermistor over a longer time (eg 150 hours) at a higher temperature (eg 85 ℃) and high humidity (eg, 85% humidity) state before and after the resistance change. 22, passive aging test Room temperature, the measurement of RF / WH Series polymer PTC thermistor long time (eg 1000 hours) at a higher temperature (eg 70 ℃ or 85 ℃) resistance before and after the change in the state. 23, hot and cold blow test At room temperature, RF / WH Series polymer PTC thermistor resistance before and after the change in the temperature cycling test results. (For example, between -55 ℃ and +125 ℃ cycle 10 times). 24, PTC intensity of β PTC thermistors have sufficient strength of PTC and NTC phenomena can not appear. β = lgR140 ° C / R at room temperature ≥ 5 R140 ° C, R at room temperature to 140 ℃ and at room temperature rated zero-power resistance. 25, Operating Characteristics PTC thermistor in the pressure-resistant flow test before and after the test should be carried out non-operating characteristics, and, where R for the conduct of non-operating characteristic thermistor test at both ends of U / I, Rn for the early measurements rated zero-power resistance value or re-measured value. 26, recovery time PTC thermistor recovery time after the action should not be larger than 60S. 27, failure mode test Failure mode during testing, the high-poly PTC thermistor may be supplied with test or in a failure state, allowing the failure mode is open circuit or high impedance state, but the whole course of the experiment may not appear low resistance state or from open flame.
