mensor PCS 400, Руководство по эксплуатации

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Since the 150 psi transducer is active, the seven
character resolution provides only three places
following the decimal point. The seventh character
is the leading zero, which is blanked.
Setup for Control Mode
To have the PCS 400 provide an output pressure to
the MEASURE/CONTROL port, connect an input
pressure to the SUPPLY port. Refer to the
Specifi-
cations section for optimum supply pressure re-
quirements. With fittings secured and source
pressure applied, press keys [2nd] [9] to get the
following display:
CONTROL PRESS:(NORM) ? PSI A
MEASURED: nnn.nnn PSI A
Input a Control Point Value
The ? prompt on the top line is asking for a new
control pressure value. The bottom line indicates
the primary (no ID after MEASURED:) transducer
is now active, and displays the current measured
pressure. Pressing [=] will return the system to the
previous control set point.
A maximum of seven characters,including the deci-
mal point, can be entered in response to the ?
prompt. It is not necessary to enter leading zeros,
nor trailing zeros after the decimal point. Thus, if
10.0000 psi is the desired output merely input [1]
[0] [=]. When entering a numerical series pressing
[CE] will clear the last digit entered, and another
[CE] will delete the now last digit, and so on.
Entering, clearing and re-entering can go on until
[=] is pressed. When [=] is engaged the system
immediately will begin to slew the output pressure
(MEASURE/CONTROL port) to the newly com-
manded value.
Incrementing the Control Point
The control point may be jogged up or down by
entering in a pressure value within the limits of the
system and pressing [+] or [–] respectively. When
the [+] or [–] keys are entered, the number entered
is immediately added or subtracted from the con-
trol pressure point. If the instrument is in CON-
TROL mode, the
PCS 400
will then drive to the newly
commanded pressure.
This function is disabled on instruments capable
of controlling negative gauge pressures.
Just like all pressure measurements with the
PCS
400 , the entered step value is in currently active
measurement units. Thus, setting a step value, then
changing the pressure units would cause the next
control mode step sequence to add or subtract the
conversion equivalent of the step value, and not the
absolute number entered.
Regulator Response
While the output pressure is changing toward the
new pressure the bottom display line will display
[U] to indicate that the output is unstable. The time
it takes to become stable, indicated by [S], is de-
pendent on several factors:
1. The differential between the beginning pres-
sure and the commanded pressure;
2. The settings for the measure FILTER WIN-
DOW and % AVERAGE;
3. The settings for the CONTROL PRESSURE
STABLE WINDOW and DELAY;
4. The external volume size. Optimum external
volume is from 0.01 to 0.5 liter.
5. And, finally, the closer the control point is to
zero pressure the more time it will take to
achieve it. Absolute units take longer than
gauge pressure units.
If the entered CONTROL value is higher than the
range of the primary transducer pressing [=] will
cause the system to emit an error sound (blap) and
re-display the ? prompt.
OPTIONAL CONTROL MODES
In addition to NORMAL and RATE control two
optional control modes are also available. The first
of these allows the control point to be commanded
by an EXTERNAL ANALOG INPUT. The other con-
trol option provides a VOLUME SELECTION such
that the
PCS 400
can perform well with either of two
widely different external volumes; up to approxi-
mately one liter for normal conditions, or up to
1000 cubic inches, or over in the optional mode.
Either of these two options must be installed at the
factory and matched to the appropriate software.
The user then accesses the feature through the
menu path of LIMITS>CONTROL LIMITS>CONT
MODE: OPTION. Refer to Section 8,
Options for
details relating to these two features.
LOCAL OPERATION
PCS 400
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