Major tech MT478 Manuale d'uso - Pagina 6
Sfoglia online o scarica il pdf Manuale d'uso per Apparecchiature di prova Major tech MT478. Major tech MT478 16. Voltage tester
1. Safety
1.4 The safely can no longer be insured if the instrument:
• Shows obvious damage
• does not carry out the desired measurements
• has been stored for too long under unfavorable conditions
• has been subjected lo mechanical stress during transport.
All relevant statutory regulations must be adhered to when using this
instrument
1.5 Safety Advices
• Depending on the internal impedance of the voltage detector there will
be a different capability of indicating the presence or absence of
operating voltage in case of the presence of interference voltage.
• A voltage detector of relatively low internal impedance, compared to the
reference value of 100kΩ, will not indicate all interference voltages
having an original voltage value above the ELV level. When in contact
with the parts to be tested, the voltage detector may discharge
temporarily the interference voltage lo a level below the ELV, but it will
be back to the original value when the voltage detector is removed.
• When the indication "voltage present" does not appear, it is highly
recommended installing earthing equipment before work.
• A voltage detector of relatively high internal impedance, compared lo !he
reference value of 100kΩ, may not permit to clearly indicate the
absence of operating voltage in case of presence of interference
voltage.
• When the indication "voltage present" appears on a part that is expected
to be disconnected of the installation, it is highly recommended
confirming by another means (e.g. use of an adequate voltage detector,
visual check of the disconnecting point of the electric circuit, etc.) that
there is no operating voltage on the part to be tested and to conclude
that the voltage indicated by the voltage detector is an interference
voltage.
• A voltage detector declaring two values of internal impedance has
passed a performance test of managing interference voltages and is
(within technical limits) able to distinguish operating voltage from
interference voltage and has a means to directly or indirectly indicate
which type of voltage is present
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