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data in the ultrasonic mode can be positive or negative. According to the
processing capacity of the ultrasonic amplifier of ZXPD-200L, -6dBuV To the test
range of 68dBuV, the larger the negative value, the smaller the ultrasonic signal
and the closer to 0uV, not a negative number! The measured data in an
interference-free environment is usually between -6dBuV and 0dBuV.
In addition to testing the amplitude of the discharge signal, ZXPD-200L can also
detect the number of discharge pulses per cycle, expressed as P / Cycle, the
size and amplitude of the pulse number comprehensively reflect the insulation
status of the switchgear, and the general pulse number is a high amplitude
below 50 The data is a typical discharge phenomenon.
In many cases, the environment of the cabinet under test will be filled with
various complex ultrasonic interferences, such as flashing fluorescent lamps,
ultrasonic mouse repellers, fans in operation, etc. Therefore, it is necessary to
measure the environmental value before testing the cabinet to judge The
interference level of the environment, when the ultrasonic environment value is
too large (for example, more than about 10dBuV), all sources of interference
need to be excluded, otherwise the excessive interference signal will mask the
real signal and affect the reading. It is recommended that when the ultrasonic
interference is large and cannot be effectively eliminated Use TEV method to
measure cabinet value.
Ultrasonic signals use air as a propagation medium and will come out from the
gap of the cabinet. Therefore, when measuring the value of the switch cabinet
