Encoder Direction; Closed Loop Drive System; Pid Control - Danfoss VLT Decentral Drive FCD 302 Design Manual

Application Examples
4 4
Illustration 4.5 Encoder Connection to the Frequency Converter
A
B
A
B
Illustration 4.6 24 V Incremental Encoder with Maximum Cable
Length 5 m

4.2 Encoder Direction

The direction of encoder is determined by which order the
pulses are entering the drive.
Clockwise direction means channel A is 90 electrical
degrees before channel B.
Counter Clockwise direction means channel B is 90
electrical degrees before A.
The direction determined by looking into the shaft end.
52
®
VLT Decentral Drive FCD 302
CW
CCW
®
MG04H102 - VLT is a registered Danfoss trademark

4.3 Closed Loop Drive System

A closed loop drive system usually comprises elements
such as:
•
Motor
•
Add
(Gearbox)
(Mechanical Brake)
•
Frequency converter
•
Encoder as feed-back system
•
Brake resistor for dynamic braking
•
Transmission
•
Load
Applications demanding mechanical brake control will
usually need a brake resistor.
WARNING
ON ALARM
Bus MS NS1 NS2
1 2 3
Illustration 4.7 Basic Set-up for Closed Loop Speed Control
Item Description
1 Encoder
2 Mechanical brake
3 Motor
4 Gearbox
5 Transmission
6 Brake resistor
7 Load
Table 4.15 Legend

4.4 PID Control

6
5
4
7