HT instruments MACROTEST G3 - Manual (Page 13)

MACROTESTG3 - COMBIG3
EN - 12
6. OPERATING INSTRUCTIONS
6.1. LOW : CONTINUITY OF PROTECTIVE CONDUCTORS
This function is performed in compliance with standards IEC/EN61557-4 and allows
measuring the resistance of protective and equipotential conductors.
CAUTION
 The instrument can be used for measurements on installations with overvoltage
category CAT III 240V to earth and CAT III 415V between inputs. Category CAT
III is suitable for measurements carried out on installations inside buildings with
low voltage (examples are distribution boards, wirings, switches, fixed installation
sockets, electric motors, industrial equipment).
 We recommend holding the alligator clip respecting the safety area created by
the hand protection (see § 4.2).
 Check that no voltage is present at the ends of the item to be tested before
carrying out a continuity test.
 The results may be influenced by the presence of auxiliary circuits connected in
parallel with the item to be tested or by transient currents.
The following operating modes are available:
Compensation of the resistance of the cables used for measurement. The
instrument automatically subtracts the value of cable resistance from the
measured resistance value. Therefore, it is necessary that this value is
measured each time the measuring cables are changed or extended.
AUTO The instrument carries out two measurements with inverted polarity and
displays their average value. Recommended mode
The instrument carries out the measurement with the possibility of setting a
duration time for testing. The operator may set a sufficiently long measuring
time (between 1s and 99s) to be able to move the protective conductors while
the instrument is carrying out the test, in order to find out a possible bad
connection.
CAUTION
Continuity test is carried out by supplying a current higher than 200mA
in case the resistance does not exceed ca. 2
 (including resistance of
the test cables). For higher resistance values, the instrument carries out
the test with a current lower than 200mA.
Fig. 6: Continuity test by means of single cables and remote lead