HEIDENHAIN iTNC 530 Service Manual page 395

You require a special appliance for the following setup. --> See "Test Adapter" on page 29 – 562.
Measuring setup
with test adapter
Test inclusive MB cable:
Figure: Keyboard test incl. cable with test adapter and multimeter
Test without MB cable:
July 2010
Note
If no test adapter is available, you can measure directly at the contacts of the MB cable or
the machine operating panel.
However, this is very cumbersome, since you must contact the right pins precisely while
pressing the key to be inspected!
Shut down the control and switch off the machine.
Disconnect the MB cable on connector X46 of the MC.
Connect the MB cable to the test adapter.
Connect the measuring lines of a multimeter to the banana jacks of the test adapter.
Insert one line into socket 37 (or 36) and connect the other line with the socket for the
respective key.
Use the respective table with the pin layout. --> See "Machine Operating Panel" on page 27
– 499.
Set the multimeter to "alarm" (acoustic signal) or to ohm measurement.
Press the key to be examined. If the key functions, the multimeter will "ring". If you use ohm
measurement, the measured resistance is approx. 1 ohm (consider the resistances of the
measuring lines and the test adapter).
Shut down the control and switch off the machine.
Dismount the machine operating panel from the console.
Disconnect the MB cable.
Instead connect the test adapter with the respective adapter cable.
Execution. --> See test incl. MB cable.
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