The shunt resistor is widely used in the digital watt-hour meter, high-precision test instrument, and all instruments and meters for measuring, sampling and shunting current, and can also be used as the main component of the current sensor. At present, the traditional shunt resistor is low in precision, and the temperature coefficient is high. It is difficult to meet the higher requirements, and many resistance manufacturers have started to develop new shunt resistors.
The shunt resistor comprises a resistor composed of a connected upper T2 copper conductive sheet, a manganese copper sheet and a lower T2 red copper conductive sheet, and a lower T2 copper conductive sheet is provided with a pin. The middle side of the manganese resistor is provided with a notch on both sides, and the two sides of the notch are respectively provided with an inward notch to form a resistive adjustment zone. In addition, the pin of the shunt resistor consists of four components. What's more, the shunt resistor also comprises a silicone molded shell coated with a resistor body, the pin of which is extended out of the silicone molded shell, and the pin is electroplated with a tin layer.
This new type of shunt resistor has the following characteristics:
Firstly, the multi-directional cut-out structure is adopted, each notch can realize the precision regulation of the resistance value, ensure the high-precision of the resistance. At the same time, the multi-cut structure avoids the problem that the local conduction band is too narrow caused by the excessive one-side resistance adjustment, so that the width of the resistance conduction band is uniform, the current density passing through is also uniform, and the whole resistor body does not have the problem of excessive local heating. Ensure the product precision, power and long-term stability.
This new type of shunt resistor has the following characteristics:
Firstly, the multi-directional cut-out structure is adopted, each notch can realize the precision regulation of the resistance value, ensure the high-precision of the resistance. At the same time, the multi-cut structure avoids the problem that the local conduction band is too narrow caused by the excessive one-side resistance adjustment, so that the width of the resistance conduction band is uniform, the current density passing through is also uniform, and the whole resistor body does not have the problem of excessive local heating. Ensure the product precision, power and long-term stability.
Secondly, the multi-cut resistive structure is adopted to ensure the power of the product. The weld melting zone of T2 copper conductive sheet and manganese copper sheet is completely removed from the groove, which solves the effect of T2 copper and electron beam welding weld on the resistance temperature coefficient and realizes the low temperature coefficient.
Thirdly, because the shunt resistor is a low resistance, it belongs to the low resistance measurement system. In the low resistance measurement, the contact resistance and the wire resistance always exist in the measuring circuit, the magnitude is about 0. 01 Ω, but the resistance to be tested is ≤ 0.001 Ω. The contact resistance and the wire resistance make the measurement result inaccurate. Therefore, the utility model adopts the design of four pins and uses the Kelvin four-wire detection principle, which is a kind of impedance measurement technology, which uses a separate counter current and voltage detecting electrode. Compared with two terminal terminals, the measurement of resistance can be carried out more accurately, thus eliminating contact resistance and line resistance.
Fourthly, obviously improving the temperature resistance and the heat conduction performance relative to the traditional bare chip, the painting or injection molding mode by adding the silicone molded shell.
Fifthly, carrying out tinning treatment on the pin by adopting an electroplating process, so that the thickness of the tin layer is consistent and the welding is convenient compared with the conventional non-processing or enameling tin treatment.
Thirdly, because the shunt resistor is a low resistance, it belongs to the low resistance measurement system. In the low resistance measurement, the contact resistance and the wire resistance always exist in the measuring circuit, the magnitude is about 0. 01 Ω, but the resistance to be tested is ≤ 0.001 Ω. The contact resistance and the wire resistance make the measurement result inaccurate. Therefore, the utility model adopts the design of four pins and uses the Kelvin four-wire detection principle, which is a kind of impedance measurement technology, which uses a separate counter current and voltage detecting electrode. Compared with two terminal terminals, the measurement of resistance can be carried out more accurately, thus eliminating contact resistance and line resistance.
Fourthly, obviously improving the temperature resistance and the heat conduction performance relative to the traditional bare chip, the painting or injection molding mode by adding the silicone molded shell.
Fifthly, carrying out tinning treatment on the pin by adopting an electroplating process, so that the thickness of the tin layer is consistent and the welding is convenient compared with the conventional non-processing or enameling tin treatment.
The new design structure of the shunt resistor has greatly improved in many aspects. Many resistance manufacturers have begun to invest in the production and manufacture of the new type resistor. This kind of shunt resistor has higher precision and lower temperature coefficient than the ordinary resistor. And can eliminate contact resistance and wire resistance, but also improve the integrity of the resistor. At present, this type of shunt resistor can be applied to various fields and has strong competitive power in the market.
