Calibrating Earth Loop Testers
According to the QLD Electrical Safety Act
2002 - Section 18 - (2)(b) : if a testing instrument can not be visually confirmed as being
correctly functioning and safe — that the instrument is tested at least every 6 months to
ensure it is in proper working order.
Line Impedance Measurement
Line Voltage Measurement
To calibrate a Loop tester first the loop impedance of the supply must be known, then several known
values of resistance must be inserted in the loop to increase the loop resistance so the tester can be
calibrated at several points. The value displayed on the tester can then be compared to that of the
known value of the resistor plus the loop resistance of the supply.
Ensure your equipment is in specification so that the loop impedance testing you do
is conducted in accordance with AS/NZS 3000 "Electrical installations - Wiring Rules
All measurements are traceable to national and international
standards via a registered NATA laboratory or a mutually recognised international testing authority. (See
NATA’s International Activities )