Fail-Safe Modules
7.2 PM-E F pm DC24V PROFIsafe Power Module
ET 200S Distributed I/O System - Fail-Safe Modules
Installation and Operating Manual, 08/2008, A5E00103686-07
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Note
Note that an inductive load connected to the DO channels can induce voltages in the case of
electromagnetic interference of a strong magnetic field. This can cause a short-circuit error
message.
Remedy:
•
Spatially disconnect the inductive loads or shield against the magnetic field.
•
Set the parameters for the readback time to 50 ms or higher.
WARNING
With a configured readback time of ≥ 50 ms, short-circuits (cross circuits) can be
suppressed with an interference signal with a frequency > 10 Hz (50:50 duty cycle).
Short-circuits (cross circuits) on an output of the same module will be detected.
7.2.5
Diagnostic functions of the PM-E F pm DC24V PROFIsafe
Behavior in Case of Supply Voltage Failure
The failure of the PM-E F pm DC24V PROFIsafe power supply is always indicated by the
PWR LED on the module (light off). This information is also provided in the module
(diagnostic entry). Either all channels of the module are passivated or, in case of channel-
specific passivation, only the relevant channels are passivated.
In the case of a voltage dip in the external auxiliary voltage, the SF LED lights up, the
module is passivated.
With the subsequent supply recovery (level must remain above the specified value for at
least 1 minute (refer to the technical specifications: voltages, currents, electrical potentials))
the SF LED goes out again, the module remains passivated. The SF LED flashes if there are
no other errors, until the error is acknowledged.
