If you de-energize the main circuit power supply, the MFDI terminals will not operate, even when you connect the external 24 V power supply to terminals PS-AC. When you set N.O. functions to H1-xx [MFDI Function Select], MFDI terminals always deactivate. When you set N.C. functions, MFDI terminals always activate. Connect the external 24 V power supply to the MFDI selection common terminal (SC).
Figure 1. Wiring MFDI Terminals
