METER TESTING DEVICE

An apparatus and method for verifying the accuracy of watt-hour meters (10) at their operational site includes applying a phantom load (46) to the meter and to a watt transducer (49). The relative watt hour readings of the meter are compared to the watt hours computed from the power to the watt transducer (49) and represented as a percentage error of the meter (10). The phantom load (46) is constituted by a loading transformer with optional load adjustments to take into account different loads to the meter (10) and there are also adjustment means to take into consideration different meter characteristics. The meter watt hour reading is determined from an articulated light generating (27) and receiving means (29) mounted in alignment with the revolving disc (30) so that light passes through the aperture in the disc to the receiving means and then signals the verifying apparatus to give an indication of the watt hour reading of the meter (10). Alternatively the reading is obtained manually.