HEIDENHAIN iTNC 530 Service Manual page 309

The PWT Phase Angle Testing Unit serves to evaluate the signal amplitude and quality as well
PWT
as the position and width of the reference mark.
--> See "PWT 10/17/18 Testing Unit" on page 29 – 568.
Using the PWT instead of the PWM 9 has advantages and disadvantages.
Advantages:
Disadvantages:
Photo: Example of a recording with the PWT 18:
A scale (1 Vpp) is connected to the PWT 18 with the signal cable and the adapter connector
ID 324555-01. The axis is traversed by a motor encoder with indirect path measurement (See
"Position Measurement via Motor Encoder (Indirect Position Measurement)" on page 18 – 311).
July 2010
Small, lightweight device
Easy handling
The PWT has an input but no output. This means that it cannot be connected between
encoder and control.
Thus, the motor encoder can hardly be checked at "operating speed".
The motor shaft or the spindle must be turned manually.
Note
Each PWT is delivered with operating instructions.
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