Kyoritsu Electrical Instruments Works KEW 4506, Instruction Manual

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6-1-1 N-E wiring check based on resistances of earth wire (E)
and neutral wire (N)
RE (RE1 + RE2) in Fig. 6-1 includes earth resistance; therefore, the
resistance value is higher than the RN (resistance of a neutral wire).
Compare the measured RE and RN and KEW 4506 judges as follows.
RE > RN……[PASS], RE < RN……[NE Reverse]
RN
Power supply
N
L
E
RE2 RE1
RE=RE2+RE1
3P outlet
Fig. 6-1
Note
This tester cannot be used as an earth resistance tester since the
frequency of test current is low: common earth resistance testers
may have different resistance measurement values.
If any of the conditions described in the following
#
CAUTION or
Note is applicable, it is recommended to use test voltage signal only
with N-E resistance measurement function turning off. See “Outlet
with earth pole (3P), resistance of earth wire (E), and turning off
resistance measurement of neutral wire (N)” in “ 7. Settings ”.
#
CAUTION
● Anti-trip-technology is applicable to RCDs rated to 30 mA or higher.
It’s not applicable to RCDs rated to 15 mA.
● RCDs rated to 30 mA or higher may trip if the circuit under test
has insulation resistance of 0.1 MΩ or less. It is recommended
to measure leakage current before conducting a test and add it
to test current of 10 mA max and confirm the total current value
doesn’t exceed the rated current.
● If insulation monitoring devices are installed, conducting a test
may activate the warning alarm. In such case, please contact
management company or owner of the test site.