Siemens SITOP SEL1200, Manual

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SITOP SEL1200-1400
Manual, 06.2019, A5E46496083-1-76
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Overview
Description
In conjunction with a 24 V power supply, the selectivity module is used to distribute the load
current across several branches and to monitor the individual currents in these branches.
Faults in the individual branches caused by overload or short-circuit are detected and
selectively switched off, so that the fault does not impact the other load circuits. This means
fast troubleshooting and minimized downtimes.
SEL1200 assumes loads that correspond to the PLC standard and can therefore
automatically buffer a voltage-free period of 10 ms. At the time of shutdown, the current
cannot be briefly limited, and as a consequence brief voltage dips below 20 V are possible.
SEL1400 is designed for demanding applications, and does not permit voltage dips below
20 V for any period of time. This is also suitable for loads/consumers that do not comply with
the PLC standard
The key benefits of the product include:
● A maximum of 8 load branches are monitored for each module
● The response threshold can be continually set for each output using a potentiometer
● Overcurrents are reliably switched off, independent of the cable length and cable cross-
section
● The 24 V supply for the other loads is maintained
● 2 adjacent outputs can be connected in parallel to increase the power rating (for max.
15 A)