Endress+Hauser RID14, Руководство по эксплуатации

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Operating the field indicator RID14
24 Hauser
field devices are configured via a Class 2 PROFIBUS DP master, such as FieldCare. The field
devices on the PROFIBUS PA segment are the slaves.
Segment coupler
From the point of view of the PROFIBUS DP master, segment couplers are transparent and
are therefore not configured in the PLC, i.e. they only convert the signals and power the
PROFIBUS PA segment.
They do not require any settings and they are not assigned an address.
Each field device on the PA segment is assigned a PROFIBUS DP address and acts like a DP
slave. Each slave is only assigned to one Class 1 master. The masters communicate directly
with the slaves:
• A Class 1 master, such as a PLC, retrieves the field device data with the cyclic service.
• A Class 2 master, such as FieldCare, sends and retrieves data from the field devices with
the acyclic service.
A link is recognized by the master and is a user of the PROFIBUS DP system. It is assigned
a DP address and is therefore no longer transparent for cyclic data exchange of the master
with the field devices. Instead it retains the device data in a data buffer which can be read
cyclically by a Class 1 master. Therefore a link must be configured.
On the PROFIBUS PA side the link behaves like a PA master. It retrieves the data cyclically
from the field devices and saves them in a data buffer. Each field device is assigned to a PA
address which may only occur once in the individual link. It can be present in another link
segment however.
For acyclic data exchange with a Class 2 master the link is virtually transparent.
Once the link address (DP address) and the device address (PA address) have been
specified, any field device can be addressed.
Since the field indicator is only a listener, it does not appear as an active user on the
bus and does not require its own bus address. Therefore the indicator can also not be
addressed directly by the master. The indicator listens to the cyclic data traffic on the
bus and presents the corresponding values on the display.
6.3.3 Device ID, addressing
Users must be addressed correctly for communication on the bus to function correctly.
Each device on the PROFIBUS PA segment is given a unique bus address between 0 and
125. Addressing depends on the type of DP/PA interface (segment coupler or link).
Since the indicator is only a listener and is not an active bus user, it does not require
its own bus address. The bus address of the device whose values are to be shown on
the indicator must be configured on the field indicator.
6.4 Configuration of the field indicator
NOTICE
The device is not explosion-protected when the housing is open
‣
The device must be configured outside the hazardous area.
To configure the device via the FieldCare Device Setup software, connect the device to your
PC. For this you will require a special interface adapter, the Commubox FXA291 (see
'Accessories' section).
The four-pin plug of the interface cable must be inserted into the corresponding socket in
the device. The USB plug must be inserted into a free USB port on the PC.
Establishing a connection