17
Note:
Further information on protective conductor resistance and testing of
portable appliances can be found in the Code of Practice for In-service Inspection
and Testing of Electrical Equipment published by the IEE.
4. Preparation before a measurement
4.1 Visual inspection
Before starting a measurement, the user should undertake visual checks on the
mains lead, case and that the correct type and rated fuse is fitted to the appliance
under test. There should also be no evidence of damage of a nature that may
impair the electrical safety of the appliance.
4.2 Battery Voltage Check
(1) Insert batteries with reference to
7. Battery/ Fuse Replacement
in this manual.
(2) Hold down Power switch 2 sec. to turn on the Tester.
(3) Check the battery indicator displayed in the upper left corner of the LCD.
If just the last one segment of the indicator remains, the battery voltage is
extremely low. Refer to
7. Battery/ Fuse Replacement
and replace batteries to
perform further measurements.
If an empty battery indicator is displayed, the battery voltage is lower than the
working voltage limit. Replace batteries immediately to keep accurate
measurement.
Battery recommendation:
Use of alkaline battery is recommended. Use of other type of batteries may cause
improper indication of battery level.
4.3 Setting
4.3.1 Null setting
The IEE Code of Practice pass level for Protective conductor resistance is 0.1
Ω
,
which is a low value. So even the resistance of Test Leads will affect the
measurement result.
The Tester
can cancel the resistance of test lead by pressing
NULL
. The
procedure of Null setting is shown below. The Null function is held in memory
even when the Tester is turned off, so there
’s no need to Null the lead resistance
every time. However, when replacing fuses or test leads, it is recommended to do
a Null setting again.
Note:
Null setting is possible at both Class l Test and Extension Lead Test. However,
only one Null value can be held in memory. For example, when the Null setting
is carried out at Class l Test, the set value will also be used for Extension Lead
Test (unless it is reset).
