Encoders; Signal Period - HEIDENHAIN TNC 426 PB/M Technical Manual

Table of Contents

6.1.3 Encoders

Position encoders report positions and movements of the machine to the

control. HEIDENHAIN contouring controls work with incremental position

encoders. The TNC 426 M and TNC 430 M contouring controls are also

compatible with encoders with an EnDat interface.

For any given distance the position encoder outputs a fixed number of signal

periods. The signal is subdivided by 1024.

To calculate the signal period, the control requires the following data:

In MP331.x, enter for each axis the length required for the number of signal

periods given in MP332.x.

In MP332.x, enter for each axis the number of signal periods for the length

given in MP331.x.

From these data the TNC calculates the quotient:

----------------------- -

Signal period =

Digital axes: If no position encoder (MP110.x = 0) is connected, the data of

the shaft speed encoder must be entered in MP331.x and MP332.x. This

also applies to speed encoders with an EnDat interface, since the

incremental track of the speed encoder is used for position feedback

HEIDENHAIN offers linear encoders with distance-coded reference marks.

The nominal increment between two fixed reference marks depends on the

encoder being used:

In MP334.x, enter for each axis the nominal increments between two fixed

reference marks.

If the number of grating periods between the reference end position and the

first reference mark exceeds the value from MP334.x, the error message Ref

mark <axis>: incorrect spacing appears. This monitoring is turned off with

MP334.x = 0.

HEIDENHAIN Technical Manual TNC 426, TNC 430