Emerson FIELDVUE DVC6200f, Инструкция по эксплуатации, Страница: 66 / 326

DVC6200f Digital Valve Controller
November 2010 54
Pressure Integral Limit Hi
Pressure Integral Limit Hi (PRESS_INTEG_HI_LIM
[47.7]) provides an upper limit to the integrator output.
The high limit is configurable from 0 to 100% of the I/P
drive signal.
Pressure Integral Limit Lo
Pressure Integral Limit Lo (PRESS_INTEG_LO_LIM
[47.8]) provides a lower limit to the integrator output.
The low limit is configurable from
−
100 to 0% of the I/P
drive signal.
Travel Pressure Control
Field Communicator
TB
>
Configure/Setup
>
Detailed Setup
>
Response Control
>
Travel Pressure Control
Travel/Pressure State
Travel/Pressure State (TVL_PRESS.STATE [41.2])
indicates if the instrument is being used for travel
control (position control) or as an I/P (pressure control)
Travel/Pressure Select
CAUTION
When using Pressure Fallback Manual
Recovery or Pressure Fallback Auto
Recovery, the valve travel has the
potential of moving rapidly causing
potential process instability when
returning to Travel Control.
Note
Travel / Pressure Select must be set to
Travel for double acting actuators.
Travel / Pressure Select (TVL_PRESS_SELECT
[41.1]) determines if the instrument is setup for
position or pressure control. Select Travel, Pressure,
Travel with Pressure Fallback/Auto recovery or Travel
with Pressure Fallback/Manual Recovery. If the travel
sensor fails, and Travel with Pressure Fallback/Auto
Recovery is selected, it will return to travel control
when the travel sensor starts working again. Travel
with Pressure Fallback/Manual recovery will stay in
pressure control until Travel Pressure Select is
changed to Travel or Travel with Pressure
Fallback/Auto recovery. It is not necessary to enable
the Travel Sensor Alert for Pressure Fallback to occur.
Travel Deviation Pressure Fallback
Travel Deviation Pressure Fallback occurs when the
instrument detects that the travel sensor is outside of
its normal range of operation or that a gross deviation
exists between set point and actual travel. It switches
to Pressure Control and no longer uses the travel
sensor to position the valve.
Travel Cutoff Hi
Travel Cutoff Hi (FINAL_VALUE_CUTOFF_HI [15])
defines the high cutoff point for the travel in percent
(%) of pre-characterized setpoint. Above this cutoff,
the travel target is set to 123.0% of the ranged travel.
Travel Cutoff Hi is deactivated by setting it to 125.0%.
Travel Cutoff Lo
Travel Cutoff Lo (FINAL_VALUE_CUTOFF_LO [16])
defines the low cutoff point for the travel in percent (%)
of pre-characterized setpoint. Below this cutoff, the
travel target is set to
−
23%. A Travel Cutoff Lo of 0.5%
is recommended to help ensure maximum shutoff seat
loading. Travel Cutoff Lo is deactivated by setting it to
−
25.0%
Pressure Cutoff Open
Pressure Cutoff Open (PRESS_CUTOFF_HI [47.1])
defines the high cutoff point for the pressure in percent
(%) of pre-characterized setpoint. Above this cutoff,
the pressure target is set to 123.0%. A Pressure
Cutoff Open of 99.5% is recommended to ensure
valve goes fully open. Pressure Cutoff Hi is
deactivated by setting it 125%.
Pressure Cutoff Closed
Pressure Cutoff Closed (PRESS_CUTOFF_LO [47.2])
defines the low cutoff point for the pressure in percent
(%) of pre-characterized setpoint. Below this cutoff,
the pressure target is set to
−
23%. A Pressure Cutoff
Closed of 0.5% is recommended to help ensure
maximum shutoff seat loading. Pressure Cutoff Closed
is deactivated by setting it to
−
25.0%
Pressure Range Hi
Pressure Range Hi (PRESS_RANGE_HI [42.7]) is the
high end of output pressure range. Enter the pressure
that corresponds with 100% valve travel when Zero
Power Condition is closed, or 0% valve travel when
Zero Power Condition is open. This pressure must be
greater than the Pressure Range Lo.
Pressure Range Lo
Pressure Range Lo (PRESS_RANGE_LO [42.8]) is
the low end of the output pressure range. Enter the
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