Limit Switches; Establishing Communication (Bus Address); Local Interface (Ssp) - Samson 3785 Mounting And Operating Instructions

Connections

3.2.2 Limit switches

For operation of the limit switches, switch-
ing amplifiers have to be connected in the
output circuit. Their function is to control the
limit values of the control circuit according
to NAMUR, thus ensuring operational relia-
bility of the positioner. If the positioner is in-
stalled in hazardous areas, the relevant
regulations must be observed.
3.2.3 Establishing communication
(bus address)
Communication between positioner, pro-
grammable logic controller, or automated
system, i.e. between PC or workstation and
the positioner(s), is established via segment
coupler (see Fig. 10) in accordance with the
PROFIBUS guidelines.
If the positioner is used in hazardous areas,
ex-proof versions of PROFIBUS-PA segment
couplers must be used.
A maximum of 32 positioners can be oper-
ated in parallel via segment coupler in par-
allel in one PROFIBUS-PA segment. In haz-
ardous areas, the number of positioners
that can be connected is reduced.
For each positioner connected via segment,
an individual, non-repetitive bus address
from 0 to 125 must be assigned. Seven
microswitches located on the inside of the
positioner hinged cover serve to enter the
bus address as binary information. The ad-
dress is made up with one switch directly as
per numbers 1,2,4 etc. or by adding up sev-
eral switch positions. The positioner is de-
livered with the address set to 126.
Make absolutely sure that the switches are
not set to center position, but all the way to
0 or 1.
28
EB 8382-1 EN
NOTE
A new bus address is not accepted, unless
you perform a new start-up of the device.

3.2.4 Local interface (SSP)

The local interface is located on the inside
of the positioner hinged cover. It is con-
nected to a PC over the serial interface
adapter (order no. 1400-7700).
The positioner can be started up over the
interface using the TROVIS-VIEW software.
It is no longer necessary to connect the de-
vice to a PROFIBUS DP/PA segment. Just
the power supply needs to be connected
over the bus terminals of the positioner (any
DC voltage power supply unit between 9
and 32 Volt).
The TROVIS-VIEW software and the device
module 3785 in the 2.02 version are re-
quired.
The positioner can also be accessed over
the SSP interface when it is connected to a
bus segment.
Cyclic and acylic data exchange are not af-
fected. The value written last is always valid
for the device parameters.