Instruction Manual Supplement
D104428X012
DVC6200 Series Digital Valve Controllers
May 2019
Using Minimum Travel Cutoffs with Fisher
™
FIELDVUE™ DVC6200 Series Digital Valve
Controllers
Minimum Travel Cutoffs
Minimum travel cutoffs limit the range of throttling directed to an actuator. If the input signal goes below the
minimum travel cutoff, the valve will be directed to go to 0% travel. This feature is available on digital valve controllers
and can be set from ValveLink software or other user interface.
105
95
85
75
65
55
45
35
25
15
5
-5
INPUT SIGNAL RAMP
115
105
95
85
75
65
55
45
35
25
15
5
-5
Input Signal (%) Low Travel Cutoff (%)
VALVE POSITION AT INPUT SIGNAL
Travel (%) Low Travel Cutoff (%)
Advantages of Using Minimum Travel Cutoffs
For Fisher severe service trims, the minimum throttling capacity (Cv) is published. The use of the minimum
throttling Cv is to ensure trim parts are operating at their full potential, minimizing trim and body erosion, vibration,
and noise potential.
With noise abatement and cavitation trims, any throttling below the minimum throttling Cv could result in damage to
the throttling area of the trim. Such damage is not exclusive to only Fisher control valves.
™
Specific to the multi-pressure stage Cavitrol
the pressure staging to become ineffective.
pressure drop occurs at the seating surfaces of the valve plug and seat ring. Damaging cavitation will occur across
these surfaces and will quickly destroy the shutoff function of the valve.
Utilizing a minimum travel cutoff in conjunction with a Fisher severe service trim could help prevent throttling below
the minimum Cv ensuring trim parts operate at their full potential.
www.Fisher.com
III trim designs, operating below the minimum throttling Cv will cause
As a result, your inlet pressure (P1) will build to the point that the full
DVC6200 Series Digital Valve Controllers
May 2019
Instruction Manual Supplement
D104428X012
Setting Minimum Travel Cutoffs
Travel Cutoff Lo defines the low cutoff point for the travel in percent (%) of pre‐characterized set point. Below this
cutoff, the travel target is set to -23%. The Travel Cutoff Lo default of 0.5% is recommended for general service valves
to help ensure maximum shutoff seat loading. For severe service valves, Travel Cutoff Lo should be above the
minimum throttling range to increase service life. Travel Cutoff Lo is deactivated by setting it to -25.0%. Refer to the
Configuration section of the appropriate instruction manual (see below) for setting Travel Cutoff Lo.
Related Documents
Refer to the DVC6200 Series Quick Start Guide, D103556X012, for installation, connection, and initial configuration
information. Refer to the appropriate instruction manual, listed below, for all other information pertaining to the
digital valve controller, including product specifications, reference materials, custom setup information, maintenance
procedures, and replacement part details.
D DVC6200 HW2 Digital Valve Controller Instruction Manual (D103605X012
)
D DVC6200 SIS Digital Valve Controller Instruction Manual (D103557X012)
D DVC6200f Digital Valve Controller Instruction Manual (D103412X012
D DVC6200p Digital Valve Controller Instruction Manual (D103563X012
Documents are available from your Emerson sales office
Neither Emerson, Emerson Automation Solutions, nor any of their affiliated entities assumes responsibility for the selection, use or maintenance
of any product. Responsibility for proper selection, use, and maintenance of any product remains solely with the purchaser and end user.
Fisher, FIELDVUE, ValveLink, and Cavitrol are marks owned by one of the companies in the Emerson Automation Solutions business unit of Emerson Electric
Co. Emerson Automation Solutions, Emerson, and the Emerson logo are trademarks and service marks of Emerson Electric Co. All other marks are the
property of their respective owners.
The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not
to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. All sales are
governed by our terms and conditions, which are available upon request. We reserve the right to modify or improve the designs or specifications of such
products at any time without notice.
Emerson Automation Solutions
Marshalltown, Iowa 50158 USA
Sorocaba, 18087 Brazil
Cernay, 68700 France
Dubai, United Arab Emirates
Singapore 128461 Singapore
www.Fisher.com
or at Fisher.com.
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E 2019 Fisher Controls International LLC. All rights reserved.
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