Optimizing The Speed Controller; Basic Trimming Procedure; Pre-Setting Machine Parameters For The Digitally Controlled Axes - HEIDENHAIN TNC 415 Technical Manual

3.2 Optimizing the speed controller

The rotary and position encoders are trimmed in sequence. The new integrated oscilloscope makes
it possible to program a step function as the output signal. The speed controller can be trimmed with
this function and with the oscilloscope without the need for any additional equipment.
The position controller is automatically inactive when starting with the step function. The axes can
only be traversed manually.
The controller can be trimmed in the sequence described. Provisional input values and input values
for monitoring are empirical values that can vary depending on the type and size of the machine as
well as on the drives, and it is therefore difficult to recommend suitable values. The characteristic
curves will also vary from one type of machine to another.

Basic trimming procedure

•
Assign the smallest possible value to the integral component of the speed controller (MP1920.x
→ 0).
•
Increase monitoring of the speed controller (MP1910.x).
•
Trim the proportional component of the speed controller (MP1940.x) as described below.
•
Trim the integral component of the speed controller.
The speed can be trimmed with or without first evaluating the reference marks.
For traversing reference marks, the highest possible values must be entered in machine parameters
MP1920.x, MP1940.x and MP1910.x to prevent the speed controller monitor responding.
MP1920.x = 200
MP1940.x = 200
MP1910.x = 300 000

Pre-setting machine parameters for the digitally controlled axes

Before trimming commences, provisional values must be entered for the corresponding machine
parameters of the speed controller.
The integral component (MP1920.x) should be as low as possible so the P component can be
trimmed without being unduly affected by the I component.
Since the input value for monitoring the speed controller is calculated as follows (error message:
"Gross positioning error 3F"):
Vlimit
MP1910.x =
MP1920.x * 9.7 µV
a greater value for the monitor must be set when entering a low integral component (MP1920.x).
Given an ideal setting of 5 for the I component (MP1920.x) and a limit voltage of 15 V, the input
value for MP1920.x is approximately 310 000.
11-12 TNC 407/TNC 415/TNC 425 3 Machine interfacing 01.98