Table 17-6: Action logic and keypad display description 
  STO means channel 1 and 2 operate simultaneously and enter Safe Torque Off. 
  STL1 means channel 1 operates. 
  STL2 means channel 2 operates. 
  STL3 means there is an error detected in the internal loop of the channel 1 or channel 2.   
  S1–DCM / S2–DCM ON: means S1–DCM / S2–DCM inputs a power supply > 11 V
DC
. 
  S1–DCM / S2–DCM OFF: means S1–DCM / S2–DCM inputs a power supply < 5 V
DC
.