Moniteur 50 Series SMART Positioners - Manual (Page 30)

Design and Method of Operation
2-12
Positioner SIPART PS2/SIPART PS2 PA
C79000-G7476-C150–01
MC
1 2 3 4 5 6
Bus
interface
Fig. 2-11 Block diagram of the bus coupling unit, devices with PROFIBUS PA
1. The EMC filter prevents malfunctions due to electromagnetic
interference.
2. The reverse polarity protection permits connection of the bus cables
in any way and makes installation errors almost impossible.
3. The electronic protection ensures that no impermissibly high current
flows in the event of a fault. That avoids overloading the bus, but
data exchange between the remaining stations not subject to
interference is still possible.
4. The bus interface contains the transmit and receive circuits for the
bus system and the control for the auxiliary power generation.
5. The device internal electronics are isolated by galvanic isolation
from the PROFIBUS PA.
6. The microprocessor interprets the bus commands, initiates device
internal actions and provides position signals, status, and device
data on the bus.
2.4 State as supplied
In the state as supplied no mechanical mounting components are at-
tached to the positioner. These have to be ordered and mounted for the
specific application in accordance with the “Assembly and Installation
Instructions”.
The connections for single and double-acting versions are prepared in
the factory as ordered.
The pneumatic connections on the rear are closed.
2.5 Optional modules
The optional modules are protected and mechanically fixed by a mo-
dule cover ((1), see Fig. 2-12)
☞
Note
To install the option modules you must first open the housing. As long
as the instrument is open, degree of protection IP65 is not ensured.
Devices with
PROFIBUS PA