rotork CK Series User Manual

Profibus Installation Manual
38
6.7 Basic Operation on Start up
Whenever a field device is powered up and it is found by the
PLC it will go through the standard Profibus procedure of
Parameterisation and Configuration before commencing Data
Exchange. This exchange can include altering the address if
the device has an address of 126 and the master supports
address changes – master class 2.
1) The first message – master sends a DIAG_req telegram.
2) The response should be a DIAG_res with diagnostic data
attached.
3) If this is correct a Set_Parameter telegram is sent with the
parameterisation data attached.
4) The response should be a Short Ack message.
5) If a correct response is received a Check_Config telegram
is sent
6) The response should be a Short Ack message.
7) If this is correct a DIAG_req telegram is sent.
8) The response should be a DIAG_res with diagnostic data
attached.
9) If DIAG is not reporting an error data exchange
commences.
The Parameterisation data is extracted from the GSD file for
the particular address of the slave device. The association
between the GSD to be used and the address is made in
the master during the configuration of the network on
the master (a table is created). The association can also be
defined in a Master 2 and sent to a Master 1 by the master
to master comms. Most master 1 devices permit the same
device type (as described in the GSD) to have different GSD
files, so allowing the GSD to be edited.
Editing the GSD file guarantees that a device coming on line
after having been switched off will have the correct settings.
If FDT or PDM changes the same parameters as those
installed by a GSD then the GSD values will replace those set
by the FDT or PDM when the device is switched off and on
again, or the PLC is powered off and back on, unless GSD
parameterisation is not permitted.
(See section 5.4 for information on the Configurations
allowed).
6.8 Static Diagnostics
Within the standard Profibus Diagnostics reply is a bit named
‘Static Diagnostic’. In the unlikely event that the PFU loses
communication with the main board to which it is connected,
this bit will be asserted to alert the user to this situation. If the
PFU is unable to communicate to the main board, the data
which is sent in data exchange communication is potentially
stale (not current). Therefore if the static diagnostic bit is
raised the user should be aware not to utilise that data and to
wait for the bit to be reset. If the bit does not de-assert itself
in a timely manner (i.e. after about 5 minutes) the user should
power cycle the actuator to regain communications.
Power On
Data Exchange
Master sends DIAG_req
telegram to slave
Master sends DIAG_req
telegram to slave
Master sends
Set_Parameter
Master sends
Check_Cong
Correct
DIAG_res
recieved
Correct
DIAG_res
recieved
DIAG
is reporting
error?
No
Yes
No
No
No
No
Correct
Response
recieved?
Correct
Response
recieved?
Fig. 23: Profibus Start Up Sequence
Profibus DP Communication
The static diagnostic bit is not expected to be seen under
normal operating conditions.
For actuators with a Profibus firmware version of V103 or
later: if the software is being updated in the CK main board,
communications to the PFU will be stopped, at this time the
Static diagnostic bit will be raised. As soon as the software
is updated and the communications to the PFU return, the
static diagnostics bit will be de-asserted. In older versions of
the Profibus firmware the same happens as described above
except that the diagnostic bit is not asserted.
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rotork CK Series Specifications

General

Brand	rotork
Model	CK Series
Category	Controller
Language	English