Example 2: Muting; Functional Description Of Safety Functions - ABB AC500-S Safety User Manual

Safety application examples
Example 2: Muting > Functional description of safety functions
Information on the used function block parameters
Function Block
SF_Equivalent_1
SF_Emergency-
Stop_1
SF_SafeStop1_1
SF_ESPE

7.3 Example 2: Muting

This example describes the safety functions for the safeguarding of a production cell. Objects are transferred
through an entry gate, which is guarded by a light curtain. This light curtain can be muted only for material
transport into the cell. The cell may be entered by the operator through a safety door. The process inside the
cell is controlled by the functional application and enabled by the safety circuit. In case of a safety demand or
an error, all hazardous movements are stopped in accordance with stop category 0.

7.3.1 Functional description of safety functions

All hazardous movements are stopped in case of:
n an opening of the door,
n an error (e.g. invalid muting sequence),
n an interruption of the unmuted light curtain (e.g., by a person),
n pushing an emergency stop button.
By pushing an emergency stop button, the operator can also stop all hazardous movements in stop category
0 (via SF_EmergencyStop and subsequent FBs).
An infringement of the unmuted light curtain stops all hazardous movements. In this application, a light cur-
tain type 2 is used, which requires a test by the FB SF_TestableSafetySensor.
For the described muting function, four muting sensors are applied sequentially (via SF_MutingSeq). Addi-
tionally, the muting phase is indicated by a lamp, which is monitored in this case (also via SF_MutingSeq).
An additional door for maintenance purposes is monitored by a door switch (via SF_GuardMonitoring).
By resetting buttons, the operator must acknowledge the detected demand of the safety functions and errors.
The initial state and the operational state of the connected actuator are checked by an external device moni-
toring. In case an error is detected, the control cannot become operational (via SF_EDM).
The process and related movements inside the production cell are controlled by the functional application.
Within the safety application, this control is enabled by the above-described safety circuit (via SF_OutCon-
trol) and drives the actuator via a safety output.
430
Input Constant
Value
S_Discrepancy- 10 ms
Time
S_StartReset FALSE
S_AutoReset FALSE
AxisID AxisID_1
MonitoringTime 100 ms
S_StartReset FALSE
S_AutoReset FALSE
Description
Maximum monitoring time for discrepancy
status of both inputs.
Manual reset when PES is started (warm or
cold).
Manual reset when emergency stop button is
released.
Drive address, supplier specific value
Time until the drive shall be stopped.
Manual reset when PES is started (warm or
cold).
Manual reset after safety demand condition is
cleared.
AC500-S 30.03.2017