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Application planning
4.2 Power budget calculation
ET 200MP Distributed I/O System
34
System Manual, 01/2013, A5E03723484-01
Remedial measures for overload
1. Check the plant configuration, e.g.:
–
Is the installed power sufficient for the number and type of the I/O modules?
– Is the interface module supplied on the front side with 24 V DC?
– Is the interface module configured correctly (parameter "Connection to supply voltage
L+")?
– Are the correct I/O modules inserted?
2. Perform corresponding changes in the configuration (e.g. insert a power supply module
before the interface module, switch on a power supply module, supply power on the front
side to the interface module, replace an I/O module).
3. The interface module periodically checks whether the connection to the backplane bus
can be recreated, and does so as soon as possible.
Exception
A power off/on of the interface module is required, for example, in the case of a voltage
drop or a hardware fault in power segment 2 or 3.
A defective power supply module must be replaced.
Proceed as follows to locate a defective I/O module in the configuration:
●
With the power switched off, pull the I/O modules one after the other, starting with the last
one.
● After pulling each I/O module, power the interface module back on and check whether the
ET 200MP starts up without any problems.
Example of a power budget - when using the GSD
1. Find out the power provided by the interface module that is supplied with 24 V DC on the
front side (from the technical specifications of the interface module).
2. Find out the required power for the I/O modules (from the technical specifications of the
individual modules). The following example uses:
–
Analog output module AQ 4xU/I ST
– Analog input module AI 8xU/I/RTD/TC ST
– Digital output module DQ 32x24VDC/0.5A ST
– Digital input module DI 32x24VDC HF
– Analog output module AQ 4xU/I ST
3. Sum up the required power.
4. If the resulting value is greater than the power that is fed in by the interface module,
deploy an additional power supply (PS) module.
–
A power supply module before the interface module leads to a combined power
(power fed by the PS + power fed by the IM)
– Each power supply module (max. 2) after the interface module spans a new power
segment (see chapter Setting up power segments (Page 36)).