Response Times - Siemens SIMATIC ET 200SP Manual

Response times

Introduction
You can find the reaction times of the F-DQ 8x24 V DC/0.5 A PP HF digital output module
below. The reaction times of the F-DQ 8x24 V DC/0.5 A PP HF digital output module are
included in the calculation of the F-system reaction time.
Definition of reaction time for fail-safe digital outputs
The reaction time represents the interval between an incoming safety message frame from
the backplane bus and the signal change at the digital output.
Times required for the calculation
● Max. cycle time: T
● Max. acknowledgment time (Device Acknowledgment Time): T
The maximum reaction time in the case of fault (One Fault Delay Time, OFDT) is equivalent
to the maximum reaction time with no faults (Worst Case Delay Time, WCDT).
Assign the parameters for maximum readback time dark test (Maximum Readback Time, T
and maximum readback time light test (Maximum Readback Time Light Test, T
STEP 7/in the TIA Portal.
Operating mode: Disable dark test for 48 hours – disabled
Maximum reaction time with no faults (Worst Case Delay Time, WCDT)
t <= 4 * T
Maximum reaction time with detection of a channel fault by readback
t <= 6 * T
Maximum reaction time with detection of a channel fault by bit pattern test
t <= 2 * T
Operating mode: Disable dark test for 48 hours – enabled
Maximum reaction time with no faults (Worst Case Delay Time, WCDT)
t <= 5 * T
Maximum reaction time with detection of a channel fault
A channel fault may not be detected until a 0-1 process value change takes place on the
corresponding channel. Please note the restrictions detailed in section Disable dark test for
48 hours (Page 19)
50
= 8 ms
cycle
cycle
+ T
cycle rb
+ maximum test period
cycle
+ T + T
cycle rb rb_lt
Digital output module F-DQ 8x24VDC/0.5A PP HF (6ES7136-6DC00-0CA0)
A
= 16 ms
DAT
) in
rb_lt
Manual, 05/2017, A5E38578424-AA
)
rb