Ashcroft GC31 - Digital Pressure Sensor - Manual (Page 13)

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9C. SELECTING STANDARD OR CUSTOM SCALING MODE
When the et( is selected in “Display Selection”, the display value of pressure for applied
pressure displays as an arbitrary scaling display. This is a function to scale the MIN/MAX dis-
play value and has NO effect on applied pressure and analog output.
9D. CUSTOM SCALING MODE
Use the MODE key to set “Decimal point position”, “Minimum pressure range display value”
and “Maximum pressure range display value” of “Display scaling”.
Example: With a pressure range of 0 to 150 psi (0 to 100% FS), main unit display of 000.0 to
150.0 (factory set) is changed to a display of 0.000 to 1.000. (User defined unit, in this case 1MPa)
d-p Dec. point position (from least significant digit): 0.1 .003
d-l Min. pressure range value: 0.0 .000
d-k Max. pressure range value: 150.0 1.000
9E. FILTER SECTION
The GC31 is equipped with 5 internal time constant filters. Use this function when pressure
fluctuations can result in erratic, difficult to read displays. The time constant for the selected
filters reflects on the switch outputs as well as the analog output.
Select “Filter Selection” with the MODE key. The message f;l is displayed for 1 sec. and
then the current setting mode’s decimal point position is displayed. Change the decimal point
position value with the
ᮡ ᮢ keys.
Entering the setting value in function setting mode resets all of the setting
f-0 No filter
f-1 Time constant 25ms
f-2 Time constant 250ms
f-3 Time constant 2.5 sec
f-4 Time constant 5 sec
f-5 Time constant 10 sec
9F. ANALOG OUTPUT SCALING
This mode is for setting the pressure for the analog output zero point and span point. Display
by analog selection is scaled as 0 to 100% (Zero point: 1Vdc, span: 5Vdc). Select “Analog
Scaling” with the MODE key.
The message a-l is displayed for 1 sec. and the current pressure’s analog output zero
point (1Vdc) is displayed as a percentage. Change the numeric value with the ᮡ ᮢ keys.
The message a-k is displayed for 1 sec. and the analog output span point’s pressure can
be set in the same way using the ᮡ ᮢ keys.
Example: With Analog output of 1 to 5Vdc at pressure range of 0 to 100 psi (0 to 100% FS),
output is changed to 1 to 5Vdc at 0 to 90 psi.
Set the analog output zero point: 0.0% FS 0.0% FS (1Vdc output with pressure range 0% FS).
Set the analog output span point: 100.0% FS 90% (5Vdc output with pressure range 90% FS).
10. SWITCH SETTINGS MODE
Setup Steps
In Measurement Mode press the key (release within 3 sec.) to change to Switch Setting Mode.
Switch Setting Mode
There are two switches, OUT1 and OUT2. Both “Hysteresis (upper/lower limit)” and “Window
Comparator” operations can be selected in the function setting mode (switch operation selec-
tion). Those two operations can be selected at once, and can be set. Both OUT1 and OUT2
can be set independently to a max on/off delay of 2 seconds. In the following explanation, if
the switch’s output conditions are met their output state will become On, and “Switch LED
(OUT1, OUT2)” will light up.
I&M011-10170 GC31:layout 4/8/10 3:26 PM Page 13