SEFRAM MW 3517BF Notice D'utilisation page 42

Smart Hold
HOLD
ZERO
The meter will beep continuously and the display will flash if the
measured signal is larger than the display reading by 50 counts.
(However, it can not detect across the AC and DC Voltage /
Current).
DCA ZERO
Remove the jaw from the conductor before performing
DCA ZERO.
Press HOLD button for over 2sec. to compensate the residual
magnetism.
Press
> 2 sec
HOLD
ZERO
Press
> 2 sec
HOLD
ZERO
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