Megger DCM1500 Manuel De L'utilisateur page 6

Zero
Using the Relative mode (REL), a stable value can be stored, the instrument
zeroed at that point, and then any variation from that value is displayed as
a direct measurement relative to the stable value.
2. Make a measurement and then press the ZERO button.
REL: Meter stores the measured value after pressing the
ZERO button.
3. REL (flashing): The meter saves the offset value. Present
value is displayed.
1. Normal: Press and hold ZERO for > 2 seconds to return
to normal operation and cancel the offset value.
Data Hold
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