Delta ASD-A2-0121 Series User Manual page 658

Chapter 10 Troubleshooting
：STO function is enabled
AL500
： STO_A loss (signal loss or signal error)
AL501
：STO_B lost (signal loss or signal error)
AL502
：STO_error
AL503
：System failure
AL555
Use DI.ARST or 0x6040.Fault Reset,
or set P0-01 to 0.
Use DI.ARST or 0x6040.Fault Reset,
or set P0-01 to 0.
Use DI.ARST or 0x6040.Fault Reset,
or set P0-01 to 0.
STO circuit error; please contact the
distributor.
N/A
ASDA-A2
10-43