1 TP-23 low level contact resistance
2 purposes
This method is to introduce a standard method to measure a supporting terminal, and the contact resistance in the condition that the insulating layer is not destroyed or melted.
3 sample preparation
3.1, the test sample is made up of a pair of matching terminals, such as a tin foot and a welding base, opposite polarity matching terminals, printed circuit boards and their mating terminals.
3.2 the wire illustrated in the specification is on line as shown in figure 2A, and the terminals are matched as shown in figure 2B.
3.3, test samples should be assembled into connectors that can work normally, and samples that cannot be installed as connectors shall not be installed in any other way. If forced installation, the strength of the contact surfaces of the matching terminals will be affected.
4 test method
4.1 test instrument
The test instruments include:
4.1.1 a milli meter with an accurate range of 2% or a precise range of exact readings to an appropriate range of + 10%.
4.1.2 a lower bit circuit has the ability to transfer and accurately measure the maximum current 100mA and the maximum open circuit potential of 20 mV. A feasible loop shown in Figure 1 (the output test current of this loop is 1mA). For AC measurement, this frequency is not more than 2KHz.
4.1.3 measurements can be carried out by DC or AC, but in any case, the DC test should be controlled.
4.2 test steps
4.2.1 connects test samples T1 and T2.
4.2.2 adds voltage to the positive direction of the test circuit, and the record voltage drop includes the polarity of the voltage Vf and the current If.
4.2.3 adds voltage to the reverse direction of the test loop, and the record voltage drop includes the polarity of the voltage Vr and the current Ir.