Profibus Actuator Control Profibus DP Option Card Installation Manual

Profibus DP Mk2 Option Card Installation Manual
Provided limited range positioning is not invoked the values 0% and
100% written to the Position DV register produce a special case
output where the command is revised so as to fully close the valve to
its tight shut off position (0%) and fully open the valve (100%).
Partial Stroke The actuator will move the valve to an intermediate position and back
to the start position provided it is at the correct end of travel position
when the command is issued. The end to start from and the amount of
travel are selected during parameterisation.
Multiport Position On multiport actuators the port to move to can be selected using this
command. The actuator will move directly to the selected port. Valves
with up to 10 ports can be controlled.
Relay Output DO1 to DO4 These 4 commands are used to energise and deenergise
the internal relays on the additional relay board in an IQ or
IQT actuator. (These outputs are referred to as S5-S8 in the standard
actuator documentation when there is no Profibus DP Module in the
actuator.) The resulting outputs can be used for operating other
equipment such as a pump or indication light. The IQ/IQT actuator is
not able to control these relays directly from the main board when the
PFU is fitted. They will maintain their last state if power is removed
from the actuator. On restoration of power the relays will be reset to
their de-energised condition and the coils will report ‘0’.
Hard Wired Open and Close These commands operate the actuator in the same way
as the open and close commands sent over the Profibus highway.
Hard Wired Stop The hard wired stop input acts as a change of state input. If the
actuator is moving, opening the Stop input will stop the actuator. If the
Stop input is already open and a Profibus command is sent to the
actuator, the Profibus command will be initiated. To stop the actuator
the hard wired input must be closed and opened again.
Hard Wired ESD (Network Disable) The hard wired ESD may be set to causes the
actuator to drive to its Emergency position. Alternately the input can
be used to disable Profibus network control. The function of the input
is determined by the parameterisation set into the PFU.
5.1.1 Controls Priority
Since there are three potential sources for control inputs the actuator and Profibus DP Module (Mk2)
assign a priority for those occasions when two or more commands are applied simultaneously.
In addition, for the IQ and IQT actuator, the remote control hard wired inputs can be used as discrete
input signals, to report the status of other devices or as control inputs. The associated Auxiliary Input
Mask parameter must be set for the IQ or IQT to select the required function. In the case of the hard
wired input for ESD this can be configured either as an ESD/DI-4 signal or as a ‘Profibus Command
Inhibit’ to prevent network control signals from moving the actuator.
30 of 66 Publication S420E V3.0 Issue 01/05