51
VLT
®
3500 HVAC
MG.35.B1.02 – VLT is a registered Danfoss trademark
Section 1Section 1Section 1Section 1Section 1
Section 2Section 2Section 2Section 2Section 2
Section 3Section 3Section 3Section 3Section 3
Section 4Section 4Section 4Section 4Section 4
204 Digital reference type (DIG. REF. TYPE)
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 referen-
ces are to be added to the other references. There is
a choice of
Sum
and
Relative
. Using the
External on/
off function
, it is possible to choose whether there is
to be a shift between control using other references
or the internal digital references.
Description of choice:
If
Sum
[0] is selected, one of the digital references is
summed (parameters 205-208) as a % of f
MAX
with the
other references.
If
Relative
[1] is selected, one of the digital references
(parameters 205-208) is summed as a % of the other
references.
If
External on/off
[2] is selected, switching can be car-
ried out via terminal 29 (parameter 405) between the
other references and one of the digital references.
NB!:
NB!:
NB!:
NB!:
NB!:
The sign only determines the direction of rota-
tion if external on/off has been selected.
Reversing via terminal 19 has no function.
Other references - this is the sum of the analogue, the
pulse and the bus references.
★
= factory setting. Text in ( ) = display text. Figures in [ ] are used when communicating with the bus.
3.6 Parameter gr
oup 2
201 Minimum frequency (f
MIN
) (MIN FREQUENCY)
Value:
0.0 - f
MAX
★
0.0 H
Z
Function:
In this parameter a minimum frequency limit can be
chosen that corresponds to the minimum speed at
which the motor is to run.
The minimum frequency can never be higher than the
maximum frequency, f
MAX
.
Description of choice:
A value from 0.0 Hz to the max. frequency (f
MAX
)
selected in parameter 202 can be chosen.
202 Maximum frequency (f
MAX
) (MAX FREQUENCY)
Value:
f
MIN
- 120 Hz
★
depending on the unit
Function:
In this parameter a maximum frequency can be cho-
sen that corresponds to the maximum speed at
which the motor is to run.
Description of choice:
A value from f
MIN
to 120 Hz can be chosen.
203 Jog frequency (JOG FREQUENCY)
Value:
0.0 - 120 Hz
★
10 Hz
Function:
The jog frequency is the fixed output frequency at
which the frequency converter runs when the Jog
function is activated.
See also a description of parameter 511.
Description of choice:
The jog frequency can be selected to be lower than
f
MIN
(parameter 201) and higher than f
MAX
(parameter
202); however, the upper output frequency is limited
by the f
MAX
that has been set (parameter 202).
References and limits, group 2..
VLT 3500 HVAC distinguishes between different types
of references.
■
NB!:
NB!:
NB!:
NB!:
NB!:
The analogue reference type is programmed in
group 4. Unused references are set at 0, or
switched out (parameters 205-208, 412-413).
Sum
[0]
Relative
[1]
