Danfoss VLT HVAC Basic Drive FC 100 Series Programming Manual page 49

Parameters
Digital input Description
function
[17] Preset ref bit 1 Enables a choice between one of the
eight preset references according to
Table 3.5.
[18] Preset ref bit 2 Enables a choice between one of the
eight preset references according to
Table 3.5.
[19] Freeze reference Freeze actual reference. The frozen
reference is now the point of enable/
condition for Speed up and Slow to be
used. If Speed up/down is used, speed
change always follows ramp 2 (3-51 Ramp
2 Ramp Up Time and 3-52 Ramp 2 Ramp
Down Time) in the range 3-02 Minimum
Reference - 3-03 Maximum Reference.
[20] Freeze output Freezes actual reference. The frozen
reference is now the point of enable/
condition for Speed up and Slow to be
used. If Speed up/down is used, the
speed change always follows ramp 2.
[21] Speed up For digital control of the up/down speed
is desired (motor potentiometer). Activate
this function by selecting either Freeze
reference or Freeze output. When Speed
up is activated for less than 400 msec. the
resulting reference will be increased by
0.1%. If Speed up is activated for more
than 400 msec., the resulting reference
will ramp according to Ramp 1 in
3-41 Ramp 1 Ramp Up Time.
[22] Slow Same as [21] Speed up, but reference
decreases.
[23] Set-up select bit Selects one of the two set-ups. Set
0 0-10 Active Set-up to Multi Set-up.
[34] Ramp bit 0 Select which ramp to use. Logic "0" will
select ramp 1 while logic "1" will select
ramp 2.
[37] Fire mode A signal applied will put the adjustable
frequency drive into Fire Mode and all
other commands will be disregarded. See
24-0* Fire Mode.
®
VLT HVAC Basic Drive Programming Guide
Digital input
function
[52] Run permissive
[53] Hand Start
[54] Auto start
[60] Counter A (up)
®
MG18B222 - VLT is a registered Danfoss trademark
Description
The input terminal, for which the Run
permissive has been programmed must
be logic "1" before a start command can
be accepted. Run permissive has a logic
'AND' function related to the terminal
which is programmed for [8] Start, [14] Jog
or [20] Freeze Output, which means that in
order to start running the motor, both
conditions must be fulfilled. If Run
permissive is programmed on multiple
terminals, Run permissive needs only be
logic '1' on one of the terminals for the
function to be carried out. The digital
output signal for Run Request ([8] Start,
[14] Jog or [20] Freeze Output)
programmed in par. 5-3*, or par. 5-4*, will
not be affected by Run Permissive.
NOTE!
If no Run permissive signal is applied
but either Run, Jog or Freeze
commands is activated, the status
line in the display will show either
Run Requested, Jog Requested or
Freeze Requested.
A signal applied will put the adjustable
frequency drive into Hand mode as if
[Hand On] has been pressed and a normal
stop command will be overridden. If
disconnecting the signal, the motor will
stop. To make any other start commands
valid, another digital input must be
assigned to Auto-Start and a signal
applied to this. The [Hand On] and [Auto
On] keys have no impact. The [Off] key
will override Hand Start and Auto Start.
Press either the [Hand On] or [Auto On]
key to make Hand Start and Auto Start
active again. If no signal on either Hand
Start or Auto-Start, the motor will stop
regardless of any normal Start command
applied. If signal applied to both Hand
Start and Auto-Start, the function will be
Auto-Start.
A signal applied will put the adjustable
frequency drive into Auto mode as if
[Auto On] has been pressed. See also [53]
Hand Start.
Input for increment counting in the SLC
counter.
3 3
3-21