①
AVT combination modules
②
Transformer
③
Measuring resistors
④
Surge suppressor
⑤
80 kHz power supply
Figure 3-6
Overview of the voltage sensing circuit
3.3.2.4
Ground fault detection
The insulation resistance is monitored against two threshold values. Here, the voltage drop at
the resistors between ground and the following artificial neutral points is compared:
• Three-phase current input (line-side)
• Three-phase output (at the motor)
If the warning threshold is exceeded, an alarm is output. If the fault threshold is exceeded, an
alarm message is output and the converter is switched off.
Description
3.3 Power unit
3rd Party LCI Control Upgrade
34
Operating Instructions, 02/2022, A5E31872818