Flowserve MX FOUNDATION Fieldbus Field Unit - Manual (Page 24)

MX/QX FOUNdaTION Fieldbus Field Unit FCd LMENIM2330-01 – 08/11
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6. OPEN/CLOSE or POSITION display allows selection of the mode of operation of the actuator.
To select operation as typically OPEN or CLOSE, select YES with OPEN/CLOSE MODE-OK?
on the display (this is the default), this will return the actuator to the CHANGE FF? display.
In position mode the host device can set the valve position to any desired value; in open/close mode
the host can only fully open or fully close the valve. The user must locally configure one of these two
modes. To select operation in POSITION mode, select NO to change the display to POSITION MODE-
OK? and then select YES. This will allow the user to configure the proportional band and deadband as
discussed below. (Default = OPEN/CLOSE)
2.6.4.1 Proportional Band
Proportional band is the range of errors between the position and demand signal that will produce
reduced speed (pulsing). The default value is 15%.
To change from default, select NO until the required value is displayed. The value is adjustable
between 1% and 100%, in 1% increments.
2.6.4.2 Deadband
The default deadband value is 2%. For error signals less than this, no motion occurs.
The deadband should be wide enough to prevent “hunting” of the actuator but as low as possible to
give adequate response to changes in the error signal. To change from the default, select NO to adjust
the value between 1% and 50%, in 1% increments to suit the application.
2.6.5 Valve Data
Valve data may be stored in the MX/QX FF transducer block for use by the host system. Refer to
Bulletin LMENIM2306 for the MX and LMENIM3306 for the QX for instructions to edit data for the
valve serial number, model and type.
2.7 MX/QX FF Device Description, Capabilities,
and Device Type Manager Files Installation
2.7.1 MX/QX FF Device Description and Capabilities Files
A Capabilities File (CF) describes the communication objects in a fieldbus device. In the Host system,
the configuration device can use DD files or CF files to configure a fieldbus system without having
the fieldbus devices online. Some host systems need both DD and CF files. Refer to your host system
documentation for the files that are needed.
The DTM file provides an interface between the actuator’s specific application software and a Network
Host Station’s Field Device Tool (FDT) frame. The DTM can be integrated into FDT frame applications
to allow users to perform offline and online parameterization, configuration, and status and diag-
nostic retrieval.
The DD files are downloaded from the Fieldbus web site (www.fieldbus.org) into the DCS workstation
or host device.
In addition, the DD and DTM files can be downloaded from the Flowserve Limitorque web site: www.
flowserve.com