Section 4. Configuration of the frequency converter
An example of the screen view for the following settings is shown in
fig. 4.4:
– referencing-unit from analog input 1
– START / STOP from digital inputs.
Regulation of output frequency of the drive and rotation speed of the
motor is carried out through selected analog input (e.g. using a
potentiometer).
4.2.4. Work with constant speeds
The system can work with one of seven constant speeds. The choice of constant speed is made by digital
inputs determined by parameters 2.30, 2.31 and 2.32 - an example in table 4.2. Values of constant speeds are defined
by parameters:
par. 2.33 – constant speed number 1 [Hz]
par. 2.34 – constant speed number 2 [Hz]
par. 2.35 – constant speed number 3 [Hz]
par. 2.36 – constant speed number 4 [Hz]
par. 2.37 – constant speed number 5 [Hz]
par. 2.38 – constant speed number 6 [Hz]
par. 2.39 – constant speed number 7 [Hz]
Table 4.2 – suggested configuration of constant speed control
Parameters
Example
Notation
2.30 W1
005 In.C5
Signal of constant speed selection W1 comes from digital input DI5 (W1 = DI5)
2.31 W2
006 In.C6
Signal of constant speed selection W2 comes from digital input DI6 (W2 = DI6)
2.32 W3
000 Sw.Off.
W3 = 0
!!! ATTENTION!!! - see structural circuit of frequency referencing-unit - section 4.2.1
As a result of choice of such parameter configuration it is possible to choice between 3 available constants through
digital inputs DI5 and DI6:
State DI5
State DI6
Effect
0
0
Drive does not operate with constant speed. At this time another referencing-unit is operating.
(See structural circuit of frequency referencing-unit - section 4.2.1)
1
0 Constant speed no. 1 (value as par. 2.33)
0
1 Constant speed no. 2 (value as par. 2.34)
1
1 Constant speed no. 3 (value as par. 2.35)
Note 1:
Digital input DI4 is default using as a source of external reset, so before using DI4 please move a source of
external reset to another digital input DI or just turn it off (par. 3.70).
Note 2:
Please make sure that DI6 works in digital input mode (fig. 2.6, jumper J5).
When constant speed referencing-unit is active display looks like it is shown in fig. 4.5.
Fc – Referencing-unit: constant frequency (speed),
Di – START through digital input.
Frequency converter MFC710 type. TWERD Power Electronics
31
B
Fc
Di
Ulin
400 V
fRef
20.0 Hz
Imot
0.0 A
Fig.4.5 - CONTROL STATE
B
A1
Di
Ulin
400 V
fRef
20.0 Hz
Imot
0.0 A
Fig. 4.4 – CONTROL STATE – referencing-unit
from analog input 1,
START using digital input
