Emerson Fisher FIELDVUE DVC6000f, Инструкция по эксплуатации

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DVC6000f Digital Valve Controllers
December 2009 6-10
Stroking the Digital Valve Controller
Output
(TB
>
Device Diagnostics
>
Stroke Valve)
Stroke Valve is used to confirm proper valve
operation. From the Transducer Block menu, select
Stroke Valve. Follow the prompts on the Field
Communicator display to select from the following:
Done, Ramp Open, Ramp Closed, Ramp to Target,
Step to Target, and Stop.
Done—Select this if you are done. All ramping is
stopped when DONE is selected.
Ramp Open—ramps the travel toward open at
the rate of 1.0% per second of the ranged travel.
Ramp Closed—ramps the travel toward closed at
the rate of 1.0% per second of the ranged travel.
Ramp to Target—ramps the travel to the
specified target at the rate of 1.0% per second of the
ranged travel.
Step to Target—steps the travel to the specified
target.
Stop—stops the command.
Trend
(TB
>
Device Variables
>
Trend)
Trend chart of Setpoint (FINAL_VALUE.VALUE
[13.2]), Travel (TRAVEL.VALUE [34.2]), and Pressure
A (PRESSURE_A.VALUE [36.2]).
Device Variables
All Block Modes
(TB
>
Device Variables
>
All Block Modes)
Block Mode: Target
The Target (TARGET [5.1]) mode is the mode
requested by the user or host system. Generally, only
one mode is allowed to be set, and it must be a
permitted mode as defined by the permitted attribute
of the mode parameter. Additionally, all cascade
targets (Cas, Rcas) must have AUTO set.
Block Mode: Actual
This is the current mode of the block. The actual
(ACTUAL [5.2]) mode may differ from the target mode
due to operating conditions of the block.
Note
Block Mode:Actual drops the AUTO bit
for the cascade targets. For example,
target mode might have Cas and Auto
set, but actual mode will only have Cas
set.
Block Mode: Permitted
The permitted (PERMITTED [5.3]) mode defines the
modes allowed for the block. This is set by the user or
host system but is restricted by the instrument to
modes supported by the instrument for the particular
block. Any change request to the Target or Normal
attribute is checked against the permitted attribute to
ensure the requested mode is permitted. When setting
the Permitted mode, there is no check against any of
the other attributes (Normal or Target modes).
Therefore, the normal or target mode attributes may
have a value that is not permitted because the
permitted attribute was modified after the Normal or
Target mode was set. This will have no effect on the
instrument until the user attempts to modify the Target
or Normal mode. At this time these attributes are
tested against the Permitted modes, thus the user
cannot change the Normal or Target modes to what
was formerly permitted.
Block Mode: Normal
The normal (NORMAL [5.4]) mode is the mode the
block should be in during normal operating conditions.
The normal mode is set by the user or host system
and can only be set to a permitted mode (see
permitted mode). The user or host system can
compare the actual mode to the normal mode and,
based on the results, determine if the block is
operating normally.
AO Control
−
Pre-Characterization
(TB
>
Device Variables
>
AO Control
−
Pre-Char)
Setpoint
Setpoint (FINAL_VALUE.VALUE [13.2]) shows the
value of the setpoint in % (percent) of ranged travel or
pressure. Setpoint is used for both travel and pressure
control. This parameter will be written directly if the
transducer block is in MAN mode, or will be written
automatically by the AO block if the transducer block
is in AUTO mode.
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