Rockwell Automation Safety Function: Hinge Switch - Manual (Page 4)

4 Safety Function: Hinge Switch
Rockwell Automation Publication SAFETY-AT096A-EN-P – November 2013
Hinge Interlock Switch Safety Function
This safety function application technique provides two safety functions.
• A door monitoring function: the removal of power from the hazard when the
safety system detects that the door has been opened
• An E-stop function: the removal of power from the hazard when the safety
system detects that the E-stop has been actuated
Safety Function Requirements
Opening the door stops and prevents hazardous motion by removing power to the
motor. Once the door is closed and the Reset button is pressed and released,
hazardous motion and power to the motor are resumed. Pressing the E-stop button
stops and prevents hazardous motion by removing power to the motor. The motor
coasts to a stop (Stop category 0). When the E-stop button is released, hazardous
motion and power to the motor do not resume until a secondary action occurs—the
Reset button is pressed and released. A fault at the door interlock switch, wiring
terminals, or safety controller is detected before the next safety demand. The safety
functions, in this example, are capable of connecting and interrupting power to
motors rated up to 9 A, 600V AC. The safety functions in this application technique
each meet or exceed the requirements for Category 3, Performance Level d
(CAT. 3, PLd), per EN ISO 13849-1 and control reliable operation per ANSI B11.19.
From: Risk Assessment (ISO 12100)
1. Identification of safety functions
2. Specification of characteristics of each function
3. Determination of required PL (PLr) for each safety function
To: Realization and PL Evaluation