Knowledge base Automation Systems Motion & Drives

3G3MV As PID - An Example

Modified on Sun, 11 May, 2025 at 10:16 PM

Introduction

This tutorial is intended as a supplement to the original manuals for the products. Therefore, use it familiarise yourself with the product, and not as a guide to complete installation. The information in the Tip! is taken from the manual:
I527 Sysdrive 3G3MV User's Manual

This tutorial shows how to set up a 3G3MV frequency converter as a PID control. For security reasons, it is recommended not to run a regular induction motor without external cooling at lower than 20-25Hz for a long time.

The system controls a ventilation fan in the engine. It uses a Pt-100 element to measure the temperature. Measurement will give out a standard 4-20mA signal, which indicates a temperature between 0 and 50 ° C. The higher the temperature, the more the fan will cool. This provides a direct regulator. The Potentiometer in front of the frequency converter is to set the desired temperature.

Just across from the green connectors are two small switches. Insert here:
SW2: 2 = ON Specifies that the signal is connected FR / FC is a power signal

The following parameters are changed in relation to the factory setup:
n001 = 8 Resets all parameters to the factory defaults, optional
n001 = 4 Provides access to all parameters
n003 = 1 Digital inputs indicating operation (S1/SC)
n011 = 50 Indicates 50Hz as the maximum rate out
n012 = 230 Specifies that the maximum voltage 230V AC out
n013 = 50 To set the rate at the maximum voltage <n011
n034 = 40 Lowest rate specified in% compared to the maximum frequency (20Hz)
n035 = 1500 Provides view of the current from 0.0 to 50.0 (° C)
n036 = 4.8 Sets brand power on the engine, variable
n128 = 6 Activation of PID control with direct effect and D-effect on the feedback signal, recommended for slow-moving systems
n129 = 0.5 Reinforcement of the feedback signal
n130 = 1 Proportional Gain [0.0 to 25.0]
n131 = 360 Integration [0.0 to 360.0] in the seconds
n133 = 100 PID offset value in%
n134 = 50 Integral Term, the upper limit in%
n139 = 1 Activation energy saving function, optional
n163 = 0.5 PID performance enhancement
n164 = 1 PID feedback signal is 4-20mA and is engaged in FR (/ FC) entrance
n001 = 0 No parameter can be changed, optional

With these settings, it will be possible to read the following:

U-01 Desired value (in ° C)
U-16 Actual value (in ° C)
U-18%-shows value from the PID function, only internally (0-100%)
FOUT current rate value out of the engine (0-100% = 0-50Hz)

By increasing the n130 and / or lessen n131, you will get a faster process but run the risk of fluctuations. Reduce n130 and / or increased n131, the response is slow and any fluctuations are long / slow. NB! To change the n130 and / or n131, n001 must be set to 4 Note that in small n130 and when n131 is large, while the deviation is small, it could take a long time before a change can be recorded on FOUT; use either U-18. Is especially true with low rates, in this case.