VLT
®
Series 3500
67
★
= ROM default setting.
✔
= Normal Danfoss setup. Text in ( ) = display text. Figures in [ ] are used when communicating with the bus.
Group 2 -- References and Limits
201 Minimum Frequency (f
MIN
) (MIN FREQUE)
Value:
00.00 to f
MAX
★
00.0 H
Z
✔
06.0 Hz fans
✔
16.0 Hz pumps
Function:
Choose the minimum frequency that corresponds to the
minimum speed at which the motor is to run. The minimum
frequency can never be higher than the maximum frequen-
cy, f
MAX
.
Description of choice:
A value from 0.0 Hz to the max. frequency (f
MAX
) selected in
parameter 202 can be chosen. This is also chosen in Quick
Set Up Menu step 6.
202 Maximum Frequency (f
MAX
) (MAX FREQUE)
Value:
f
MIN
to 120 Hz
★
depending on the unit
✔
60.0 Hz
Function:
Choose a maximum frequency that corresponds to the
maximum speed at which the motor is to run. The maximum
frequency can never be lower than the minimum frequency,
f
MIN
.
Description of choice:
A value from f
MIN
to 120 Hz can be chosen. Consult factory
before setting a maximum frequency greater than the rated
frequency of the motor. This is also chosen in Quick Set Up
Menu step 7.
203 Jog Frequency (JOG FREQUE)
Value:
0.0 to 120 Hz
★
10 Hz
Function:
The jog frequency is the fixed output frequency at which the
drive runs when the jog function is activated. A jog button is
not provided on the 3500 Series, but the function is avail-
able by ap24 V DC to terminal 29. See parameter
405.
Description of choice:
The jog frequency can be selected to be lower than f
MIN
(pa-
rameter 201) and higher than f
MAX
(parameter 202).
NOTE:
When the jog function is activated, the drive will run
at the jog speed (preset speed) regardless of the
external speed reference signal. Be sure that the
system can be operated at this speed whenever the
jog function is activated.
204 Digital Reference Type (DIG. REF.)
Value:
★
Sum (SUM)
[0]
Relative (RELATIVE)
[1]
✔
External on/off function (EXT. ON/OFF)
[2]
Function:
It is possible to define how the internal digital references
are to be added to the other references. There is a choice
of
Sum and Relative. Using the External on/off function
switches between other references and the internal digital
references.
Description of choice:
If
Sum [0] is selected, the selected digital reference per-
centage is a percentage of f
MAX
. This is added to the other
references. For example, if f
MAX
= 60 Hz and f
MIN
= 0 Hz, the
digital reference is 20% and the analog references are 40
HZ, the total reference is:
.2 x 60 Hz + 40 Hz = 52 Hz.
If
Relative [1] is selected, the selected digital reference per-
centage is a percentage of the other speed references. This
is added to the other speed references. For example, if f
MAX
= 60 Hz, f
MIN
= 0 Hz, the digital reference is 20%, and the
analog references are 40 Hz, the total reference is:
.2 x 40 Hz + 40 Hz = 48 Hz.
If
External on/off [2] is selected, switching can be carried
out via terminal 29 (parameter 405) between the other ref-
erences and one of the digital references, as a percentage
of f
MAX
.
NOTE:
The sign only determines the direction of rotation if
external on/off has been selected. Reversing via
terminal 19 has no effect.
