Presentation; General Presentation; The Megohmmeter; Accessories - Chauvin Arnoux C.A 6521 Notice De Fonctionnement

1. PRESENTATION

Terminology
The term "continuity" will be used to mean a resistance
measurement performed with a current of at least 200 mA (with
the measured resistance lower than 20 Ω) in accordance with
the IEC 61557 norm, to distinguish it from a resistance
measurement (C.A 6523 and C.A 6525) performed with a current
that is not predefined.

1.1. General Presentation

1.1.1. The Megohmmeter

These portable instruments function with batteries or a
rechargeable battery. They can be used to check the insulation,
continuity and voltages and to measure resistances. They help
to ensure the safety of electrical installations. The acquisition,
processing and display of the measurements are managed by
a microprocessor,
They offer a large number of advantages such as automatic
detection of a dangerous voltage on the MΩ calibre terminals
(with blocking of any insulation testing if V > 25 V), protection of
the instrument against external voltage surges, improved
operator safety through automatic discharging of the high voltage
from the equipment tested, automatic shutdown of the instrument
to optimize the battery charge life, a large LCD display with a
wide range of indicators that is very easy to read, etc. And,
depending on the model, backlighting of the LCD (C.A 6523
and C.A 6525), programming of the thresholds (C.A 6523 and
C.A 6525), the possibility of compensated leads for continuity
(C.A 6523 and C.A 6525), and display of the duration of the
measurement (C.A 6525).

1.1.2 Accessories

■ Shoulder bag (delivered with standard instrument, see § 10)
When placed in the shoulder bag, the instrument can either be
carried on the shoulder to transport it or around the neck for
use. This leaves the users' hands free to perform the
measurements. Since the instrument is perpendicular to the
chest, it is easy to read.
At the bottom of the shoulder bag, underneath the instrument,
there is a pocket for the leads, the touch prod, the crocodile
clamp and the remote control probe.
■ ■ ■ ■ ■ Remote control probe (option, see § 10)
This probe is used with the C.A 6523 and C.A 6525. These are
equipped with the special connector required to connect it to
the instrument.
It can be used for all the measurements, including activation of
insulation testing, using the yellow button which works in exactly
the same way as the button on the instrument.
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