Single-phase electric energy meter sampling circuit

Abstract

The invention discloses a single-phase electric energy meter sampling circuit. An input end of a power transformer T1 is connected with a live wire through a live wire conductor; the live wire conductor is grounded; both ends of manganin R0 are in live wire connection; one end of a resistor R1 is connected with a sampling line through one end of the manganin R0, and the other end of the resistor R1 is connected with one end of a capacitor C1 and one end of a high-resistance resistor Z1; one end of the resistor R2 is connected with the other end of the manganin R0 through one sampling line; the other end of the resistor R2 is connected with one end of the capacitor C2 and one end of a high-resistance resistor Z2; the other end of the capacitor C1, the other end of the capacitor C2, the other end of the high-resistance resistor Z1 and the other end of the high-resistance resistor Z2 are all grounded; the circuit also comprises resistors R11, R12 and Rc. The sampling circuit can still sample normally under the condition that the live wire conductor is broken or one sampling line is broken, so that the repair rate is greatly reduced, and the maintenance cost is greatly reduced to a certain extent.

Description

technical field [0001] The invention relates to the technical field of electric energy meters, in particular to a single-phase electric energy meter sampling circuit. Background technique [0002] The prior art single-phase electric energy meter sampling circuit such as figure 1 As shown, it includes resistors R1, R2, capacitors C1, C2, manganin R0, two high resistance resistors Z1, Z2 and power transformer T1, the two high resistance resistors Z1, Z2 are equivalent to resistors, the resistance value is mega European level, but in fact it is the internal equivalent impedance of the measurement chip pins to ground; one input end of the power transformer T1 is connected to the live wire through a live wire, and the live wire is grounded; the two ends of the manganese copper R0 Even fire wire connection; one end of the resistor R1 is connected to one end of the manganese copper R0 through a sampling line, and the other end of the resistor R1 is connected to one end of the capa...

AI Technical Summary

Problems solved by technology

During the transportation of the electric energy meter, due to vibration or its own welding problems, it is easy to cause the live wire to break, or one of the sampling lines to break, or both of the sampling lines to break, or the live wire and the two sampling lines to be disconnected. disconnected, so that the impedance of the two arms of the sampling circuit of the single-phase electric energy meter is unbalanced, resulting in inaccurate or non-measurement situations

In the above case, both the sampling wires are broken or both the live wire and both the sampling wires are broken. Higher chance of breaking

However, if all the electric energy meters in the above situation are returned to the factory, the maintenance cost will be greatly increased.

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