The utility model discloses a positive and negative metering
voltage sampling circuit, which comprises a
resistor R78, a
resistor R79, a
resistor R80, a resistor R81, a resistor R82, a resistor R86, a resistor R87, a resistor R88 and a resistor R89, the resistor R88, the resistor R87, the resistor R81, the resistor R79, the resistor R78, the resistor R80, the resistor R82, the resistor R86 and the resistor R89 are sequentially connected in series, a first grounding circuit is electrically connected between the resistor R88 and the resistor R87, the two ends of the resistor R88 are connected with a grounding
capacitor C80 in parallel, and the two ends of the resistor R88 are connected with a second grounding circuit in parallel. The two ends of the resistor R87 are connected with a grounding
capacitor C81 in parallel, and the end, away from the resistor R86, of the resistor R89 is electrically connected with a second grounding circuit. According to the circuit structure provided by the utility model, the metering
chip U6 and the metering
chip U2 are respectively connected to the UAP point and the V3P point by utilizing the current direction change of
alternating current, so that bidirectional
voltage metering can be realized in the same circuit,
voltage sampling resistors can be saved, the number of the sampling resistors is effectively reduced, the occupied area of a PCB (
Printed Circuit Board) is relatively reduced, and the cost is relatively reduced; and the market competitiveness is improved.