Omron NE1A-SCPU01 - 07-2009 Operation Manual page 264

Reaction Time
11-5-3 Verifying the Reaction Time
Serious injury may possibly occur due to loss of required safety functions. Check
to make sure that the reaction times calculated for all safety chains meet the
required specifications.
230
Network reaction times #1 and #2 will be 24 ms each, based on a safety con-
nection EPI of 6 ms. The reaction times are obtained using the following equa-
tion:
Reaction time (ms) = Switch reaction time
+ Safety I/O Terminal input reaction time
+ Network reaction time #1
+ NE1A-SCPU01 remote input/remote output reaction time
+ Network reaction time #2
+ Safety I/O Terminal output reaction time
+ Actuator reaction time #2
= Switch reaction time
+ ON/OFF delay time (DST1-ID12SL-1) + 16.2
(= Input reaction time of DST1-ID12SL-1)
+ 24
+ 6
+ 24
+ 6.2 (= Output reaction time of DST1-MD16SL-1)
+ Actuator reaction time
= 76.4 + ON/OFF delay time (DST1-ID12SL-1)
+ Switch reaction time + Actuator reaction time
Always confirm that the reaction time calculated for each safety chain satisfies
the required specifications. If the reaction time exceeds the required specifica-
tions, consider the following items and correct the design of the network for
that reaction time requirements are satisfied.
• The network reaction time can be reduced by shortening the EPI. This,
however, will also reduce the network band that can be used for other
connections.
• The cycle time of the NE1A-series Controller is automatically calculated
based on the size of the program, the number of connections, and other
factors. The cycle time can be reduced by using separate NE1A-series
Controllers for safety chains that require high-speed reaction times.
!WARNING
Section 11-5