HEIDENHAIN iTNC 530 Service Manual page 263

If the 24 V supply for the Control-Is-Ready output drops during machine operation, the
EMERGENCY STOP chain is interrupted. The EXTERNAL EMERGENCY STOP error message is
displayed:
Troubleshooting
July 2010
Note
For this purpose the Control-Is-Ready signal output must be integrated correctly into the
EMERGENCY STOP chain. --> See "Annex: Principle of Function of the iTNC 530 Control"
on page 2 – 657, See "During Start-Up" on page 3 – 661!
Measure the voltage on X34.
Check the wiring. (Use the circuit diagram of the machine tool for this purpose.)
Examine the power supply units.
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