Safety Integrated - Industry - Siemens

Ex. No.
4.6
Description Parameters
The external device monitoring circuit for a dependent, second
OSSD has the same function as the standard external device monitoring
circuit. This circuit monitors the second channel, but does not
have any effect on the enabling of channel 1.
In this example, the magnet contact is monitored by the second
external device monitoring circuit.
The Monitored start - monitor input device requires activation of the
start input of the corresponding OSSD as an additional start requirement.
If the AND link of all the monitoring, linking and external device
monitoring circuit devices of an OSSD delivers an ON result, and if the
start requirements have been fulfilled, the monitored start - monitor
input start device relays the enabling request to the output device.
When the circuit is enabled (ON), the output circuits (2 relays each)
of both OSSDs are simultaneously activated by the Stop category 1-
two relay outputs output device.
When the circuit is switched off (OFF), the output circuit of OSSD 1 is
immediately switched off without a delay. The output circuit of the
dependent OSSD is switched off after the set switch-off delay has
elapsed. The switch-off delay can be set between 0 s and 300 s in
100 ms increments. It is not possible to switch the system on again
until both output circuits have switched off.
124 Functional Example No. CD-FE-I-035-V10-EN