Zener 8000-V, Руководство по установке

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ZENER 8000-V Installation Manual _
16 IM00165
L1
L2
L3
+
M1
Induction
motor
M3
Output
line
reactor Input
line
reactor
Rectifier section Inverter section
M2
Earth leakage currents in IT supply system environments
These notes are provided to raise awareness of issues associated with capacitively coupled earth leakage
currents in 1000V VSD installations using “IT” electrical supply systems. Typically these will be mining industry
applications. These notes are general in nature and should not be considered in any way to represent an
alternative to appropriate professional engineering advice.
A general explanation of “IT” and “TN” electrical distribution earthing systems is provided as an appendix.
Basic VSD power circuit
The ZENER 8000-V rectifies the incoming AC line to produce a DC voltage that feeds and inverter stage
consisting of 6 IGBT switches. The switches are operated to create a pulse width modulated (PWM) output
voltage between the M1/M2/M3 output terminals. The voltage between the output terminals provides the
necessary variable frequency and variable voltage power source to operate the motor over a wide speed range.
Voltage between phases