Profibus DP Mk2 Option Card Installation Manual
46 of 84
Publication PUB088-005-00_1017
5.2.4
Digital Inputs Reporting the Profibus Card Condition
GSD Parameterisation Permitted
If the actuator and card is being parameterised using either the FDT,
PDM programmes and the associated device description files, or (for
the IQ/IQT only) using the Infra-red tool, then the ability to alter the
card parameters by the GSD may need to be removed. The status of
this bit shows if, during parameterisation after connection or power up,
the settings in the GSD file will be used or the existing settings will be
retained. When the bit is true (1), GSD parameterisation is permitted.
Control Contention
If an incorrect value is transmitted in the ACTCON register then there
will be no control action and this bit will be true (1) until a valid
ACTCON value is received. Only one bit may be set in the ACTCON
register at a time.
Partial Stroke in Progress
When the actuator is performing a partial stroke this bit is true (1).
Once the action is complete the bit is reset (0). If the partial stroke is
interrupted by a new command then the bit will be reset.
Part Stroke Error
In order to perform a partial stroke of the valve, the starting position is
specified as either the open limit or the close limit. If the actuator is
commanded to perform a partial stroke when it is not in the correct
starting position or when it is in a mid position this error is generated
and the bit will be set (1).
There is a timer associated with Partial Stroke that is set during
parameterisation to a value long enough to cover a successful partial
stroke operation from end to mid position and back to the end. If the
actuator fails to complete the partial stroke within the time set then this
bit will be true (1).
Once set, the Part Stroke Error bit will be reset to 0 when the actuator
next moves at least 2% by either a manual or automatic operation.
Note:
On start up of the card following connection to the bus the PLC will conduct a
sequence of events including setting the Configuration of the card and then adjusting
the card Parameters. The configuration will be the one selected for this particular card
when it was commissioned onto the Profibus highway (see later). The parameterisation
will be in accordance with the values in the GSD file associated with the specific
actuator. It is possible to set the card so that GSD parameterisation is ignored; this
then allows the actuator to be powered off and on again without resetting any
parameter values.
