Operating instructions
Bit 02, DC brake
Bit 02 = “0” leads to DC braking and stop. Braking current and duration are set in par. 2-01
DC
Brake current
and 2-02
DC Braking time
. Bit 02 = “1” leads to ramping.
Bit 03, Coasting
Bit 03 = “0” causes the frequency converter to immediately "let go" of the motor (the output
transistors are "shut off"), so that it coasts to a standstill.
Bit 03 = “1” enables the frequency converter to start the motor if the other starting conditions
have been fulfilled.
NB!
In par. 8-50
Coasting select
a selection is made to define how Bit 03 gates with the
corresponding function on a digital input.
Bit 04, Quick stop
Bit 04 = “0” causes a stop, in which the motor speed is ramped down to stop via par. 3-81
Quick
stop ramp time
.
Bit 05, Hold output frequency
Bit 05 = “0” causes the present output frequency (in Hz) to freeze. The frozen output frequency
can then be changed only by means of the digital inputs (par. 5-10 to 5-15) programmed to
Speed
up
and
Speed down
.
NB!
If
Freeze output
is active, the frequency converter can only be stopped by the fol-
lowing:
• Bit 03 Coasting stop
•Bit 02 DC braking
• Digital input (par. 5-10 to 5-15) programmed to
DC braking
,
Coasting
stop
or
Reset and coasting stop
.
Bit 06, Ramp stop/start:
Bit 06 = “0” causes a stop, in which the motor speed is ramped down to stop via the selected
ramp down
parameter.
Bit 06 = “1" permits the frequency converter to start the motor, if the other starting conditions
have been fulfilled.
NB!
In par. 8-53
Start select
a selection is made to define how Bit 06 Ramp stop/start
gates with the corresponding function on a digital input.
Bit 07, Reset
Bit 07 = "0" does not cause a reset. Bit 07 = "1" causes the reset of a trip. Reset is activated on
the signal’s leading edge, i.e. when changing from logic "0" to logic "1".
Bit 08, Jog
Bit 08 = "1" causes the output frequency to be determined by par. 3-19
Jog speed
.
VLT
®
Profibus 4. How to Control the Frequency Converter
MG.33.C4.02 - VLT
®
is a registered Danfoss trademark
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