Hardware Planning and Assembly
SIWAREX FTA
4-15
- SIMATIC operation with a default setting regarding the behavior for a CPU-stop,
if the SIMATIC CPU is stopped or is already in Run state,
- the operating mode defined in the HW-config if the CPU switches from stop to
RUN status.
This means that stand-alone operation is switched off automatically as soon as the
module recognizes application in SIMATIC.
Deactivating stand-alone operation can be done with instruction “13 Switch off
stand-alone operation”.
4.3 EMC-Compatible Structure
SIWAREX FTA is a high-precision measurement device which has to dependably
measure the slightest signal. Proper assembly and cabling is an absolute must for
interference free operation.
4.3.1 Definition: EMC
EMC (Electromagnetic Compatibility) describes the ability of an electrical device to
function in a defined electromagnetic environment without being influenced by its
surroundings and without negatively influencing the surroundings.
4.3.2 Introduction
Although SIWAREX FTA was developed for use in industrial environments and
meets high EMC specifications, you should do some EMC planning before
installing your controller to determine and take into account any possible
interference sources.
4.3.3 Possible Effects of Interference
Electromagnetic interference can influence the automation system and SIWAREX
FTA in various ways:
-
Electromagnetic fields that have direct influence on the system
-
Interference that infiltrates the environment through the bus signals
(PROFIBUS-DP/PROFINET etc.)
-
Interference through process cabling (e.g. measurement lines)
-
Interference infiltrating the system through the power supply and/or protective
ground
Error-free functionality of the SIWAREX FTA can be influenced by interference.
4.3.4 Coupling Mechanisms
Depending on the means of distribution (conductive or non-conductive bound) and
the distance between the interference source and the device, interference can be
introduced through four different coupling mechanisms into the automation system.
Galvanic coupling