Major tech MT790, Instruction Manual

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3. SAFETY INFORMATION 

This Meter complies with the standards IEC61010: in pollution degree 2, 
overvoltage category (CAT. III 600V, CAT IV 300V) and double insulation. 
CAT. III: Distribution level, fixed installation, with smaller transient 
overvoltages than CAT. IV CAT.IV: Primary supply level, overhead lines, 
cable systems etc. 
Use the Meter only as specified in this operating manual, otherwise the 
protection provided by the Meter may be impaired. 
In this manual, a 

Warning

 identifies conditions and actions that pose 

hazards to the user, or may damage the Meter or the equipment under 
test. 
A 

Note

 identifies the information that user should pay attention to. 

4. RULES FOR SAFE OPERATION

•  Before using the Meter inspect the case. Do not use the Meter if it is 

damaged or the case (or part of the case) is removed. Look for cracks 
or missing plastic. Pay attention to the insulation around the 
connectors. 

•  Inspect the test leads for damaged insulation or exposed metal. 

Replace damaged test leads with identical model number or electrical 
specifications before using the Meter. 

•  Do not apply more that the rated voltage, as marked on the Meter. 
•  When measurement has been completed, disconnect the connection 

between the test leads and the circuit under test, remove the test leads 
from the input terminals of the Meter and turn the Meter power off. 

•  Do not carry out the measurement when the Meter's back case and / or 

battery door is opened to avoid electric shock. 

•  When the Meter working at an effective voltage over 30V in AC, special 

care should be taken. 

•  Use the proper terminals and function for your measurements. 
•  Do not use or store the Meter in an environment of high temperature, 

humidity, explosive, inflammable and strong magnetic field. The 
performance of the Meter may deteriorate after dampened. 

•  Do not use the Meter if the surface of it is wet or the user's hands are 

wet. 

•  When using the test leads, keep your fingers behind the finger guards.
•  Replace the battery as soon as the battery indicator       appears. With 

a low battery, the Meter might produce false readings that can lead to 
electric shock and personal injury. 

WARNING:

 To avoid possible electric shock or personal injury,  and to 

avoid possible damage to the Meter or to the equipment under test, 
adhere to the following rules: