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3 GENERAL USE
The measurements are made directly (voltage, frequency, and current if a clamp is connected) or by
pressing the TEST key.
Voltage and/or frequency measurements are accessible in all "active" settings of the switch.
3.1 AUTOMATIC CHECKS
3.1.1 POSITION OF PHASE (MAINS SOCKET) CHECK
Upon connection, the instrument measures the voltages between conductors "L" and "N" (U
LN
),
between conductors "L" and "PE" (U
LPE
), between conductors "N" and "PE" (U
NPE
), and between the
voltage probe - if a rod is connected to the terminal (P) - and conductor "PE".
The conductor that has the highest potential is taken to be the phase, designated by the letter "L" and
identified by one of the following displays:
or
The measuring cable supplied with the instrument bears a white mark making it possible to determine
the position of the phase on the mains socket.
The instrument also determines the frequency for any frequency
≥
15.3Hz or DC
3.1.2 THE PROTECTIVE CONDUCTOR (PE) CHECK
In a loop measurement (ZLOOP) or an earth measurement in a live condition (REARTH), when the
TEST key is pressed, the instrument first measures the potential difference U
C
between the local earth
(user's potential, via the TEST key) and the "PE" terminal.
If U
C
> U
L
, where U
L
is the limit contact voltage (U
L
= 25 or 50V: see § 3.2: SET-UP), the instrument
indicates that it is impossible to make a measurement.
If a measurement is triggered, the instrument then monitors voltage U
NPE
: if it increases by more than
20V, the instrument stops the measurement and reports an error.
Pressing the TEST key again causes a return to voltage measurement mode.
In a loop measurement with 2 wires (ZLINE position), measurement of the potential
between the earth and the "PE" conductor is omitted
3.1.3 MEASUREMENT CONDITIONS CHECK
For a measurement to be authorized, in addition to the above two checks (determination of the
position of the phase and of the voltage of the PE conductor), the following conditions must be
satisfied:
-
U
LN
, U
LPE
and U
NPE
< 550 V,
-
voltage: f < 450Hz; current: 20Hz < f < 450Hz,
-
loop or earth measurements in live condition: f = 15,3 to 65Hz,
-
correct connection of the measuring cables (terminals connected and not interchanged).
When a measurement is disabled, there is an error message (see § 7), an error beep, and the
flashing display of the symbol.
Summary of Contents for C.A 6454
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