MENU ITEM FUNCTIONS
6
Control Value (
)
Displays the control input value in mA or Volts.
Option Value (
)
The Option Value
displays the current or voltage
value at the analog output option terminals.
Setup Menu (
)
See Table 2 and Figure 2 for setup options.
Tuning Menu (
)
See Configuring Menu
Tuning Coefficients,
Table 4 & Figure 2 for setup and PID Tuning Infor-
mation.
Analog Output Connection (
)
Sets the mode of operation for the Analog output option to
or
. Setting option to
configures the Output
Option to proportinally follow the output pressure in mA or
volts. The value is displayed in Option Value
. Setting
option to
configures the Output Option to be used
as an independent keypad settable output signal in mA or
Volts and is displayed in the Option Value
. See Table
5, Quick Setup Guide.
Output Pressure (
)
Displays the actual output pressure in the default
PSIG units. BAR and kPa units can be displayed
based on configuring (
) and (
) as discussed
in the Pressure Conversion section. See Table 6.
Setpoint (
)
Configuring the Model T7900/T7950 to control
output pressure
, the Setpoint
menu
item on the Main menu displays the setpoint in
terms of output pressure. Selecting Setpoint
with the control input channel
in Local
mode causes the numberic characters to blink
unitl the value required is reached via the up/
down buttons and entered. Use Control Input
configured in Remote
for controlling
the output pressure proportional to the signal
value at the control input channel terminals. This
is defined by the calibration relationship of
,
,
, and
in the Configuration Menu
.
Setpoint
displays the current pressure
setpoint value.
Control Input (
)
Control Input
configures the control input chan-
nel function. Setting
in Remote
mode, the
control input channel functions as setpoint control
to the Model T7900/7950. Control Input
set to
LOCAL
chooses the Setpoint
using the
keypad to control the output pressure. In this mode,
the Model T7900/7950 control functions disregard
the analog input channel.
NOTE: The Control Input
and the
Analog Output Connection
have
four setting combinations that confi-
gure the Model T7900/7950 operation.
See Table 5, Quick Setup.
Calibration Menu (
)
See section 'Control Input Used as Setpoint
Control' , Table 3 & Figure 2 for setup options.
Look Ahead Function (
)
Using the Look Ahead
function can reduce the gain
error and enhance the Model T7900/T7950 response
characteristics in most linear control applications. To
improve response characteristics, the Look-Ahead
function predicts the required internal control correction
for a specific setpoint based on the characterizing
values
and
. To achieve optimum look-ahead
characteristics, the Configuration
menu items
and
must be set with the Model T7900/T7950
operating with the supply pressures they will use in their
applications.
Pressure Unit Conversion (
) and (
)
The Model T7900/T7950 Output Pressure
can
display in any required pressure unit. To convert to other
pressure units, set the values of menu items Numerator
and Denominator
. Values entered in
and
form a fractional conversion factor that converts the
base units of pressure (psig) in the Model T7900/T7950
into the required units. The converted (new pressure)
unit is determined by the expression
Converted Pressure
Unit
= (pressure in psig) x (N/D). Consult a conversion
table to obtain a conversion factor for the required units,
convert into a fractional form, and enter it into the Model
T7900/T7950 using
and
.
Setup Menu (
) Operation
Control Units
Sets control input units in mA
or volts
.
Values are input in the Configuration Menu
as
and
.
Analog Output Option Units (
)
To change the Analog Output Option Units
between voltage
and current
enter the
appropriate unit on the
menu.
