Lenze 8400 motec - Manual (Page 501)

Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05 501
13 Application examples
13.1 Sequence control
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13 Application examples
This chapter contains different application examples for the 8400 motec.

Tip!
The required parameters can be easily set in the »Engineer« via the All parameters. In the
"parameter list" category all parameters of the 8400 motec are listed.
13.1 Sequence control
Task:
Two pumps are to keep the water level in a reservoir constant. The second pump is to be switched
off if the consumption allows it.
Solution:
Pump 1 controls the water level and, if required, switches pump 2.
• For the control, the ( L_PCTRL_1 ) process controller is used.
• For switching on pump 2, the GP function "Analog comparison" ( L_Compare_1 ) is used. In order
to prevent the permanent switching on and off of pump 2, a high hysteresis (95 %) is set for
comparison.
• The GP function "Binary delay element" ( L_DigitalDelay_1 ) prevents short runtimes and a short
switch-off time of pump 2.
[13-1] Basic signal flow
motec 1 motec 2
/starter
0 ... 50 % 0 % / 50 %
MCTRL
F
OUT
RFR
Start / Stop
F
OUT
= 100 %
Digital
Delay
Compare PCTRL
RFR
IN1
Act speed
Analog
Input SET
ACT
1
C00472/1
70 %
C00472/2
100 %
C00681
95 %
Hysteresis
V
I N2
V
I N1
V
OUT
4 ... 20 mA
IN2
Set speed