Fantech VLT 2800 Series Instruction Manual page 60

Freeze output freezes the present output frequency
(in Hz). The output frequency can now only be
changed via Speed up and Slow down .
NOTE
If Freeze output is active the variable
frequency drive can only be stopped if
you select Motor coast, Quick stop or
DC braking via a digital input.
Speed up and Slow down are selected if digital
control of the speed up/slow down is required. This
function is only active if Freeze reference or Freeze
output frequency has been selected.
If Speed up is active the reference or output frequency
will be increased, and if Speed down is active the
reference or output frequency will be reduced. The
output frequency is changed via the preset ramp
times in parameters 209-210 Ramp 2.
One pulse (logic '1' minimum high for 14 ms
and a minimum break time of 14 ms) will lead
to a speed change of 0.1 % (reference) or 0.1
Hz (output frequency). Example:
Term. Term. Freeze ref/
29 33 freeze outp.
0 0 1
0 1 1
1 0 1
1 1 1
Freeze reference can be changed even if the variable
frequency drive has stopped. The reference will also
be saved if the AC lines are disconnected
Catch-up/Slow-down is selected if the reference
value is to be increased or reduced by a
programmable percentage value set in parameter
219 Catch-up/Slow-down reference .
Slow-down Catch-up
0 0
0 1
1 0
1 1
Ramp 2 is selected if a shift between ramp 1
(parameters 207-208) and ramp 2 (parameters
209-210) is required. Logic '0' leads to ramp 1
and logic '1' leads to ramp 2.
= factory setting. () = display text [] = value for use in communication via serial communication port
MG.28.A8.22 - VLT is a registered Danfoss trademark
Function
No speed change
Speed up
Slow down
Slow down
Function
Unchanged speed
Increase by % value
Reduce by % value
Reduce by % value
VLT® 2800 Series
Preset reference, lsb and Preset reference, msb
makes it possible to select one of the four preset
references, see the table below:
Preset ref. Preset ref.
msb lsb
0
0
1
1
Preset reference on is used for shifting between
remote-controlled reference and preset reference.
It is assumed that External/preset [2] has been
selected in parameter 214 Reference function. Logic
'0' = remote-controlled references are active, logic
'1' = one of the four preset references is active,
as can be seen from the table above.
Thermistor is to be selected if a possibly integrated
thermistor in the motor is to be able to stop the
variable frequency drive if the motor overheats.
The cut-out value is 3 k .
If a motor features a Klixon thermal switch instead, this
can also be connected to the input. If motors operate
in parallel, the thermistors/thermal switches can be
connected in series (total resistance lower than 3 k ).
Parameter 128 Motor thermal protection must be
programmed for Thermistor warning [1] or Thermistor
trip [2] and the thermistor is to be connected between
a digital input and terminal 50 (+ 10 V supply).
Function
0 Preset ref. 1
1 Preset ref. 2
0 Preset ref. 3
1 Preset ref. 4
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