![background image](http://html1.mh-extra.com/html/danfoss/vt2800-series/vt2800-series_design-manual_507920088.webp)
VLT
®
2800 Series
Function:
In these parameters 302-307
Digital inputs
it is possible
to choose between the different enabled functions
related to the digital inputs (terminals 18-33).
Description of choice:
No operation
is selected if the frequency converter is
not to react to signals transmitted to the terminal.
Reset
resets the frequency converter after an
alarm; however, a few alarms cannot be reset
(trip locked) without first disconnecting the mains
supply and reconnecting it. See table under
List
of warnings and alarms
. Reset is activated on
the leading edge of the signal.
Coasting stop inverse
is used for making the frequency
converter "let go" of the motor immediately (output
transistors are "turned off"), which means that the motor
runs freely to stop. Logic
’
0
’
leads to coasting to stop.
Reset and coasting inverse
are used to activate
motor coast simultaneously with reset. Logical
’
0
’
means motor coast stop and reset. Reset
is activated on the falling edge.
Quick stop inverse
is used for activating the quick-stop
ramp down set in parameter 212
Quick stop
ramp-down time.
Logic
’
0
’
leads to quick stop.
DC-braking inverse
is used for stopping the motor by
energizing it with a DC voltage for a given time, see
parameters 126, 127 and 132
DC brake
. Please note
that this function is only active if the value in parameter
126
DC braking time
and 132
DC brake voltage
is
different from 0. Logic
’
0
’
leads to DC braking.
Stop inverse
, a logic
’
0
’
means that the motor speed
is ramped down to stop via the selected ramp.
None of the stop commands mentioned
above are to be used as repair switches.
Note that the frequency converter has more
voltage inputs than L1, L2 and L3 when the DC bus
terminals are used. Check that all voltage inputs are
disconnected and that the prescribed time (4 mins.)
has passed before repair work is commenced.
Start
is selected if a start/stop command is required.
Logic
’
1
’
= start, logic
’
0
’
= stop.
Latched start
, if a pulse is applied for min. 14 ms,
the frequency converter will start the motor, provided
no stop command has been given. The motor can
be stopped by briefly activating
Stop inverse
.
Reversing
is used for changing the direction of
rotation of the motor shaft. Logic
’
0
’
will not lead
to reversing. Logic
’
1
’
will lead to reversing. The
reverse signal only changes the direction of rotation,
it does not activate the start. Is not active at
Process
regulation, closed loop
. See also parameter 200
Output frequency range/direction
.
Reversing and start
is used for start/stop and for
reversing with the same signal. No active start
command is allowed at the same time. Acts as
latch start reversing, provided latch start has been
chosen for terminal 18. Is not active for
Process
regulation, closed loop
. See also parameter 200
Output frequency range/direction
.
Start clockwise
is used if you want the motor shaft only
to be able to rotate clockwise when started. Should
not be used for
Process regulation, closed loop
.
Start anticlockwise
is used if you want the motor
shaft only to be able to rotate anticlockwise
when started. Should not be used for
Process
regulation, closed loop
. See also parameter 200
Output frequency range/direction
.
Jog is used to override the output frequency
to the jog frequency set in parameter 213
Jog
frequency
. Jog is active regardless of whether a
start command has been given, yet not when
Coast
stop
,
Quick-stop
or
DC braking
are active.
Freeze reference
freezes the present reference.
The reference can now only be changed via
Speed up
and
Speed down
. If
freeze reference
is active, it will be saved after a stop command
and in the event of mains failure.
Freeze output
freezes the present output frequency
(in Hz). The output frequency can now only be
changed via
Speed up
and
Speed down
.
✭
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.28.E9.02 - VLT is a registered Danfoss trademark
88