Siemens SIMATIC ET 200M Operating Instructions Manual page 104

Maintenance and service
7.4 Replacing the IM 153-2 or IM 153-2 FO
IM 153-2: Pull out the bus connector
You can remove the bus connector with worn-through bus cable from the PROFIBUS DP
interface without having to interrupt the data traffic to the bus.
Note
A data communication error may occur on the network.
On both ends, the bus segment must always be connected to the terminating resistor. For
example, this is not the case when the last slave with the bus connector is deactivated. As the
terminating resistor in the bus connector obtains its voltage from the node, the function of
the terminating resistor is affected.
Ensure that the nodes to which the terminating resistor is connected are always supplied with
voltage.
Tip: Use the PROFIBUS terminator as an active bus connector.
IM 153-2 FO: Removing the fiber-optic cable
When you remove the FOC from the IM 153-2 FO, then all following DP slaves are also no
longer available for the DP master!
Do not look directly into the opening of the optical transmit diodes.
The emitted light beam could damage your eyes.
Replacing In the redundant system
Note
Always switch off the power before you replace the IM 153 -2 / -2 FO!
If you carry out a replacement in an energized state, the specified switchover times cannot be
guaranteed and the I/O modules could fail for a certain time and output "0".
If you replace the IM 153 -2 / -2 FO in a redundant configuration, the following applies:
"ACT" LED is on:
The IM 153 -2 / -2 FO is the active one of the two
IM 153 -2 / -2 FO.
104
CAUTION
"ACT" LED is off:
The IM 153 -2 / -2 FO is the passive one of the two
IM 153 -2 / -2 FO.
This IM 153 -2 / -2 FO can be replaced without
performing a switchover in the ET 200M.
Operating Instructions, 04/2022, EWA-4NEB7806006-09
ET 200M