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General Information
General Information
Installation category definitions
IEC 61010-2-030 defines measurement categories II to IV relating to transient over-voltages and locations within
electrical installations.
Examples of electrical installation category rating are:
Category II - a mains socket outlet,
Category III - the wiring between the socket outlets and the consumer unit,
Category IV - the supply to the consumer cut-out from the distribution network transformer.
For further information on category ratings visit the relevant product page on www.megger.com.
Safe working practice
It is important that before the instrument is used, and when testing is completed, the functions of the instrument
are proven to be working. This is to ensure that a hazardous condition is not mis-reported by the instrument as
being safe. For example:
By checking the voltage range correctly measures a known power source on a separate electrical source, prior to
measuring the circuit to be tested and then checking it at the end of testing, a live circuit is less likely to be mis-
reported as dead.
The Megger MTB7671 test box is available for checking all electrical functions of the multi-function tester
(excluding Ground tests) between calibration dates.
Cleaning and maintenance
The MFT70 should only be opened or repaired by an approved Megger service or by Megger Instruments Limited.
To clean the instrument, use a damp cloth or isopropyl alcohol if available. To clean the display window only use a
lint free cloth. Refer to “Repair and Warranty” on page 38.
