ABB AC500-S Safety User Manual page 320

Safety times
Safety function response time
Fig. 120: SFRT in AC500-S system with PROFINET components and safe CPU to CPU communication (example:
SM560-S-FD-1 to SM560-S)
All terms in this figure are further explained
page 320.
The following terms are defined in Fig. 118, Fig. 119 and Fig. 120 (in alphabetical order):
● Device_WD1 (safety I/O time for inputs) is an internal input device watchdog time in ms
which includes:
–
–
–
–
● Device_WD2 (safety I/O time for outputs) is an internal output device watchdog time in
ms which includes:
–
–
–
● F_Host_WD (safety logic time) is the watchdog time in ms equal to three times of the set
value using SF_WDOG_TIME_SET POU on the safety CPU (variable as parameter through
SF_WDOG_TIME_SET POU and depends on the number of F-Devices, safety application
program and system configuration)
● F_WD_Time1 and F_WD_Time2 are the first and the second watchdog times in ms for
receipt of the new valid PROFIsafe telegram (variable as parameter and depends on system
configuration). It consists of different "black channel" components, like fieldbus cycle time
(PROFINET), I/O bus time and update time for safety CPU and communication modules.
320
Ä on
Input delay (variable as parameter; not used for safety analog inputs which have an
internal input delay of 67.5 ms in the worst case instead)
Ä Table 4 "Input delay accuracy for DI581-S" on page 63
Input delay accuracy
Ä Table 6 "Input delay accuracy for DX581-S" on page 88
Test pulse low phase (fixed to 1 ms and optional (only if test pulses are used); not used
for safety analog inputs)
Two times internal cycle time (fixed; AI581-S ➔ 4.5 ms, DX581-S ➔ 5.5 ms and DI581-
S ➔ 6.5 ms)
Internal safety output device cycle time (fixed; DX581-S ➔ 5.5 ms)
Output processing time in DX581-S (fixed to 1.5 ms)
Hardware delay (current dependent, e.g., ~1 ms (747 µs at 5 mA) and the maximum of
4 ms under the maximum output current of 500 mA). If more precise values are needed,
please contact ABB technical support.
3ADR025091M0208, 12, en_US 2020/06/19