Improved Approach to High Voltage Breakdown Testing
Original Publication Date: 1984-Sep-01
Included in the Prior Art Database: 2005-Feb-04
The illustrated circuit conducts a simple, automatic continuity test of a product's primary circuit prior to the test for dielectric breakdown. This precludes the acceptance of a product as having passed its dielectric test when, due to an open primary, the test had never actually been applied. With specific reference to the drawing, a product to be tested is plugged into the outlet and the door of the safety enclosure is closed, making a circuit from a 110 VAC source through RLY2-1(N/C), through the product's primary circuit, RLY2-2(N/C), the photomod, and back to the 110 VAC line through the door switch. The two 51K resistors are provided to prevent an internally ground shorted product from receiving AC power. The photomod maintains a high impedance in series with the product.