Chauvin Arnoux CA 10 Notice De Fonctionnement page 29

Select the measurement range using the range switch (see 2 p.25). The user
should be aware that the choice of a low measurement range implies a high test current.
If you don't know the order of magnitude of the resistance, we advise using the
highest range (200 W /0.01A).
Read the value on the LCD (see 5 p.25) directly in the unit indicated by the range switch.
The appearance of the «-» sign on the left of the display indicates poor connection
of the measurement leads:crossing the voltage or current leads. Simply change
over the current connections C1 and C2, or the voltage terminals P1 and P2
(see 1 p.25) CHAUVIN ARNOUX connection accessories (see p.26) are marked
by colours and avoid these problems.
The appearance of the «1» digit on the left of the display indicates range overload,
so you should change to a higher range. Nevertheless, if the digit «1» is still
displayed even on the highest range (200 W /0.01A) this means that the value of
the resistance under test is above 199.9 W (max. value of the measurement range
of the instrument).
To obtain higher accuracy, reduce the range and on the range switch read the value
of the test current corresponding to this new range to guard yourself against
problems due to the injection of a current that is too high.
To switch off the instrument, press the ON/OFF button again. the display should
then go out.
NOTE:
During any operation, it is important to keep a watch on the different indicators which
were explained on § LED INDICATORS.
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