Safe Torque Off 6-11 
890CS Common Bus Supply - Frames B & D; 890CD Common Bus Drive and 890SD Standalone Drive - Frames E & F 
STO Technical Specification 
Inputs Specification 
STO A Input and STO B Input comply with IEC61131-2. Note: inputs do not have hysteresis. 
Recommended input voltage for low level:  0V to +5V 
Recommended input voltage for high level:  +21.6V to +26.4V 
Typical input threshold voltage:  +10.5V 
Absolute maximum input voltage:  -30V to +30V 
Typical input current @ 24V  9mA 
Indeterminate input range:  +5V to +15V. Function is undefined. 
Fault detection time
3
:  2.3sec typical; 
  < 1.6sec will not generate a fault 
  > 3.0sec will generate a fault. 
  
3
 A fault is defined in this context as Channel A and Channel B inputs being in opposite logic states.