Heidenhain: Evaluation Electronics 636287-01 (ND 287)

Evaluation Electronics for Metrological Applications

Evaluation Electronics for metrological applications offer numerous functions for measured data acquisition and statistical evaluation of measured values.

QUADRA-CHEK evaluation electronics for profile projectors, measuring microscopes, 2-D and video measuring machines as well as CMMs measure points on 2-D contours, depending on the version either automatically or manually by crosshairs, by optical edge detection or by video camera with real-time display of the live image and integrated image processing. For 3-D contours, such as planes, cylinders, cones and spheres, the measurement points are saved by probing with a touch probe.

In the optional CNC version, they also operate as full-fledged controls for axis positioning and can automatically execute measuring programs.

ND 287 | The evaluation unit for measuring and testing stations

Thanks to its wide range of functions, the ND 287 evaluation unit for one axis is predestined for measuring and inspection stations, but is also intended for simple positioning tasks. The universal encoder input permits connection of all incremental encoders with 11 µAPP and 1 VPP signals and absolute encoders with the EnDat 2.2 interface from HEIDENHAIN.

Execution

The ND 287 features a sturdy aluminum die-cast housing. A graphic TFT monitor displays the measured values, the status and the soft-key row. The splash-proof full travel keyboard is built for the workshop.

Functions

The ND 287 features numerous functions for measuring and processing individual positions, for example sorting and tolerance check mode, minimum/maximum value storage, measurement series storage. These data make it possible to calculate mean values and standard deviations and display them in histograms or control charts. With its modular design, the ND 287 permits connection of a second encoder for sum/difference measurement or of an analog sensor, for example for temperature compensation. The ND 280 was conceived to perform simple measuring and positioning tasks (see the brochure Digital Readouts and Linear Encoders for Manually Operated Machine Tools).

Data Interfaces

The ND 287 has serial interfaces for measured value transfer to a PC or printer, for input/output of parameters and compensation value lists, and for diagnostics:

The measured value transfer can be started at the ND keyboard, through an external command, through the RS-232-C/V.24 software command CTRL B, or by an adjustable internal clock.

Sorting and Tolerance Checking

With the sorting function of the ND 287, workpieces can be inspected for dimensional accuracy and divided into classes. The result is indicated in the status display in color or with symbols; in addition, a corresponding signal is available at the switching outputs.

Display Freeze

To be able to read the display reliably in spite of quickly changing values you can send an external signal to hold the display. The true position value is counted internally.

Combination with a Second Encoder

A second encoder or a sensor on the ND 287 can be connected through an optional encoder module or analog module input assembly. The data from two encoders can be combined through mathematical operands. The result and the two measured values are saved. This permits further areas of application, such as the sum/difference display of two encoders or temperature compensation through a temperature sensor.

Recording and Evaluating Series of Measurements

The ND 287 provides a measured-value memory for recording series of measurements. The measurement value, minimum, maximum or difference can be displayed during the serial measurements. In addition, the displayed value can be checked with the classification function for compliance to tolerances. The saved measured values are evaluated and represented as:

Statistical Process Control (SPC)

For SPC, the ND 287 saves up to 1000 measured values in a nonvolatile FIFO memory. They are evaluated with the following functions: