| 摘要 |
The insulation resistance (R) between two circuits is determined by measuring their leakage impedance. A regulated supply (1) powers the equipment and a constant low frequency alternating voltage is generated (3), connected to test terminals (B1,B2). Another circuit (2) determines the voltage maxima and minima, with others sampling (7) and referencing (6) the current at maximum voltage.The resulting signal is converted (8) for display (O), to indicate the insulation resistance. The low frequency generator may include a voltage/current regulator (30), with a voltage generator (31) controlled by a low frequency filter (22) output, time base (20) and ring counter (21), followed by a peak clipping circuit (32). The output is capacitor (4) coupled with a parallel output capacitor (C).
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