Lenze c250-S, Руководство по эксплуатации

Страница: 224 / 264

7 Connection
Examples
EDBC250SIO | 2.0
224
7.2 Safety Function with Two-channel Input
For applications requiring single-fault safety such as EMER-
GENCY OFF, EMERGENCY STOP, you may connect two digital
inputs to two switching devices of safe sensors and further to
the safety module.
A software module of the safety PLC provides the required
analysis of the switching contacts.
"FB_ESTOP" is a safety-related component intended to moni-
tor an EMERGENCY STOP button. FB_ESTOP can be used for
both the emergency switch off function (stop category 0) or –
with the assistance of additional peripherals - the EMER-
GENCY STOP function (stop categories 1 or 2).
FB_ESTOP can be used to monitor single and two-channel
EMERGENCY STOP switches. The component's discrepancy
time monitoring is enabled for two-channel applications.
Discrepancy time monitoring: The discrepancy time defines as the maximum length of time
both inputs may be in different states without the component interpreting this as a fault. Dis-
crepancy time monitoring starts whenever the state of one input changes. The components
will detect a fault if, at the end of the discrepancy time, both inputs are in different states.
Safety ratings of two-channel sensors
The safety ratings listed in the table below reflect the maximum values a two-channel safety
function may achieve when using two inputs of the safe I/O module. They solely apply to the
part of the safety function covered by the safe I/O module. All components involved in the
safety function must be taken into account in order to assess whether the desired safety rat-
ings are achieved. The quality of the safe sensor is of crucial importance with particular regard
to the safety function of analysing a two-channel sensor. Use approved sensors only (e.g. to EN
60947-5-1 / -5.) and take account of your switching device's B10d value. The safety assessment
of the safety function must also consider the safety ratings of the safe PLC used in the applica-
tion.
Safety ratings when applying the module's test pulses to two-channel contact-type sensors
Highest safety integrity level to EN 62061:2010 SIL3
Highest safety integrity level to IEC 61508:2010 SIL3
Category and highest performance level to EN ISO 13849-1:2015 Cat. 4/PL e
Hardware fault tolerance (HFT) in two-channel application
(IEC 61508:2010/EN)
1
(a fault of the application need not cause the safe-
guard to fail)