35
●Measurement in ATT mode requires longer time than that is required for the other
measurements (approx. 7 sec). When measuring a circuit with a large electrical noise, the
'Noise' Message is displayed on the LCD and the measurement time will be extended to 20
sec. If the 'NOISE' symbol is displayed on the LCD, it is recommended to disable the
ATT mode and take a measurement (RCDs may trip).
●If an impedance of 20Ω or more is measured between L-N during measurements with ATT
enabled, “
L-N>20Ω
”is displayed on the LCD and no measurement can be made. In this
case, disable the ATT function and make measurement. When a large contact voltage
exists in the circuit under test,“
N-PE HiV
”is displayed on the LCD and no measurement
can be made. In this case, disable the ATT function and make measurement. Be aware
that if the ATT mode is disabled, RCDs may trip.
●Measured result may be influenced depending on the phase angle of the distribution
system when making measurement near a transformer and the result may lower than the
actual impedance value. Errors in measured result are as follows.
●ATT mode is automatically enabled after one measurement when making a measurement
with ATT mode disabled.
Ω
L-PE
230
V
50.0Hz
L-PE
L-N
!
ATT:ON
System Phase
Difference
Error
(approx.)
10°
-1.5%
20°
-6%
30°
-13%
Fig.31 Connection for using Outlet
