Complementary information
The total delay time of the feedback signal is determined by the:
•
Signal propagation time between the
Enable
output and the physical input of the
external device
•
Switching time of the external device
•
Signal propagation time of the external device and the
EDM feedback signal
input
If you need the signal at the
Enable
to be delayed, you must implement this delay by
using another function block that is located upstream of the
External device monitoring V1
function block. Otherwise, errors may result.
7.6.2.5.2
Fast shut off V1
Overview
The function block minimizes the switch-off time of a safety switching path. The switch-
off time depends on the logic execution time. The switching on again of the output
depends on the logic execution time.
You can implement a simple logic within the function block. The function block also
provides the option to implement a bypass to bridge the fast shut off function.
Important information
WARNING
Restricted safety with bypass
In the case of non-compliance, it is possible that the dangerous state of the machine
may not be stopped or not stopped in a timely manner.
b
Make sure that the system or machine is in a safe status when using the Bypass
function.
b
Ensure the mandatory use of other protective measures while the Bypass function
is active, e.g., that the machine is in safe setup mode so that it cannot endanger
people or parts of the system while the bypass is active.
b
Take into account the longer response time when the bypass is deactivated when
planning the application.
Prerequisites
•
All relevant physical inputs and outputs for the
Fast shut off V1
function block are
connected to the same module.
•
Relevant input elements are connected directly to the inputs 1 … 8 of the function
block. There must be no logic between the input elements and the inputs on the
function block.
•
The outputs of the function block must have a direct switch-off effect on the
output element. The downstream logic must not contain any
OR V1
function block.
Principle of operation
Table 89: Inputs
Input
Description
Input 1
Data type: Boolean
Input 2 … Input 8
(optional)
Bypass
(optional)
Data type: Boolean
7
CONFIGURATION
82
O P E R A T I N G I N S T R U C T I O N S | Flexi Compact
8024589/2020-11-10 | SICK
Subject to change without notice