Chauvin Arnoux MA 400D-1000 Bedienungsanleitung Seite 21

If the measurement exceeds the display capacity (400 A), the
device displays 399.9, blinking.
If the measurement is too low (see § 3.2), the device displays
dashes.
If the edges of the signal are too steep or its peak factor is
too large, the device displays OL.
2.2.3. FREEZING THE MEASUREMENT
If you want to freeze the display of a measurement, press
the HOLD key.
The HOLD symbol is displayed.
The device continues to make measurements, but the display
is frozen. To release it, press the HOLD key again.
2.2.4. SEARCH FOR MAXIMUM
To search for a maximum, for example a spike lasting at
least 200 ms, press the HOLD (MAX > 2s) key for more
than two seconds.
The Max symbol is then displayed; the device starts making
measurements a few seconds later.
The device compares each new measurement to the one
displayed. If the new measurement is greater than the old, it
replaces it in the display.
To return to the real-time display mode, press the HOLD
(MAX > 2s) key again.
HOLD
M
AX
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