Operating The Et 200M With Process I/O On A Grounded Supply - Siemens SIMATIC ET 200M Operating Instructions Manual

Assignment planning
3.6 Configuring the electrical structure
Rules on the Power Consumption and Power Loss of an ET 200M
For their operation, the S7-300 modules use the necessary power from the backplane bus as
well as, if necessary, from an external load power supply.
• The current consumption of all signal modules from the backplane bus must not exceed
the electrical output that the IM 153-x can supply to the backplane bus.
• The PS 307 power supply is dependent on the current consumption from the 24 V load
power supply; this is the result of the total of the current consumption of the signal
modules and all other connected loads.
• The power loss of all the components in a cabinet must not exceed the maximum thermal
rating of the cabinet.
Tip: When establishing the required dimensions of the cabinet, ensure that the
temperature inside the cabinet does not exceed the permissible 60°C even where external
temperatures are high
You will find the values for the power consumption and power loss of a module under the
technical specifications of the relevant modules.
3.6.2

Operating the ET 200M with process I/O on a grounded supply

The following gives information on the overall configuration of an ET 200M to a grounded
supply (TN-S-network). The topics covered here are:
• Switch-off organs, short-circuit and overload protection in accordance with DIN VDE 0100
and DIN VDE 0113
• Load power supplies and load circuits
Grounded supply
With grounded supplies the neutral line of the network is grounded. A simple contact to earth
between a live cable and ground or a grounded part of the unit triggers the safety organs.
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Operating Instructions, 04/2022, EWA-4NEB7806006-09
ET 200M