Shut-Down Sequence - Danfoss VLT AFE 302 Operating Instructions Manual

Crane System Design

3.10 Shut-down Sequence

It is recommended to send a STOP signal to the AFE before shutting down the power.
Auxiliary Hardware
Actions
The motor speed is
reduced to zero.
DC voltage level
is reduced.
Open the contactor.
DC voltage level is
down to zero
The DC capacitor can be discharged
with the external resistor, which
expedites the discharge process.
Illustration 3.15 Shut-down Sequence Flow Cart
®
VLT Active Front End AFE 302 Operating Instructions Liebherr
AFE/Inverter Drives
All the inverters control
to reduce the speed
to zero, if it is not zero.
"Running" signal is o
when the speed is zero.
AFE is deactive.
®
MG.33.X2.02 - VLT is a registered Danfoss trademark
Control PLC
Stop Sequence
Send INV Stop signals
to all the inverters
No
"Running" o ?
Yes
Send AFE Stop signals
to the AFE.
Wait for 1sec.
Send Open signals to
the AFE and Mains
contactors.
End of Stop
Sequence
3
No
Wait for 5min?
Yes
Protection Mode
: The wait period is tentative.
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