Siemens SINAMICS S120 Installation And Start-Up Manual page 161

Response time for "Safe brake control" function
The following values can be specified for the response times when the function is
selected/deselected via input terminals:
S Typical response time
4 x safety monitoring clock cycle CU (r9780) + inputs/outputs sampling time
(p0799)
S Maximum response time that may occur in the event of a fault
8 x safety monitoring clock cycle CU (r9780) + inputs/outputs sampling time
(p0799)
Examples:
Assumption:
Safety monitoring clock cycle CU (r9780) = 4 ms and
inputs/outputs sampling time (r0799) = 4 ms
t = 4 x r9780 (4 ms) + r0799 (4 ms) = 20 ms
R_typ
t = 8 x r9780 (4 ms) + r0799 (4 ms) = 36 ms
R_max
Parameter overview (see List Manual)
S p0799
S r9780
S r9880
E Siemens AG, 2004. All rights reserved
SINAMICS S120 Installation and Start-Up Manual, 12/04 Edition
CU inputs/outputs sampling times
Safety Integrated monitoring clock cycle (Control Unit)
Safety Integrated monitoring clock cycle (Motor Module)
SINAMICS Safety Integrated (Booksize)
Safe brake control (SBC)
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