Minipa CA-1000 Manual De Instrucciones página 4

3. Press the trigger to open the transformer jaw and involve the conductor.
The measurement can not be made correctly when more than one
conductor is involved by the jaw, because a mutual current cancellation
of different conductors could happen. The jaw must be completely
closed after do de measurement. The best accuracy is taken when de
conductor is center in the jaw.
Fig 2.
Fig 3.
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