HEIDENHAIN iTNC 530 HSCI Service Manual page 160

Example 3:
PLC supply voltage interrupted at the PLD-H 16-08-00 input/output module
It may not be possible to switch the control on (depending on which PLC outputs are concerned).
The PLD-H 16-08-00 is not powered with 24 V (PLC) and shows WARNING condition:
The green LED for the 24 V PLC power supply is not lit; neither are the associated orange LEDs for
the PLC outputs:
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