2.5.4 Example of Process PID Control
Illustration 2.23 is an example of a process PID control used
in a ventilation system:
Temperature
Fan speed
Temperature
transmitter
Heat
Heat
generating
process
Cold air
130BA218.10
100kW
n °CW
Illustration 2.23 Process PID Control in a Ventilation System
In a ventilation system, the temperature can be set from -5
to +35 °C (23–95 °F) with a potentiometer of 0–10 V. To
keep the set temperature constant, use the process control.
The control is inverse, which means that when the
temperature increases, the ventilation speed is increased as
well to generate more air. When the temperature drops,
the speed is reduced. The transmitter used is a
temperature sensor with a working range of -10 to +40 °C
(14–104 °F), 4–20 mA.
Transmitter
96 97 9998
91 92 93 95
50
12
L1 L2
L1
PEL3
W PEVU
F1
L2
L3
N
PE
130BD373.10
18
53
27
55
54
M
3
Illustration 2.24 2-wire Transmitter
1. Start/stop via the switch connected to terminal
18.
2. Temperature reference via potentiometer (-5 to
+35 °C (23–95 °F), 0–10 V DC) connected to
terminal 53.
3. Temperature feedback via transmitter (-10 to
+40 °C (14–104 °F), 4–20 mA) connected to
terminal 54.
Function Parameter
number
Setting
Initialize the frequency converter. Parameter 14-2
2 Operation
Mode
[2] Initialisation - make a power cycling - press reset.
1) Set motor parameters:
Set the motor parameters according to nameplate
data.
1-2* As stated on motor nameplate.
Perform a full AMA. Parameter 1-29
Automatic
Motor
Adaption
(AMA)
[1] Enable complete AMA.
2) Check that motor is running in the correct direction.
When the motor is connected to the frequency converter with straight forward phase order as U-U; V-V; W-W, the motor shaft usually
turns clockwise seen into shaft end.
Press [Hand On]. Check the shaft direction by
applying a manual reference.
Product Overview
VLT
®
Midi Drive FC 280
32 Danfoss A/S © 03/2016 All rights reserved. MG07B102
22
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