8270A/8370A
Operators Manual
32
Operation
This section explains the pressure control settings of the Product.
Operating Modes
The product has three operating modes: Control, Measure, and Vent.
Control Mode
– When in Control mode, the Product actively controls pressure
as defined by the Setpoint and will keep the pressure near the Setpoint per the
active control mode (see
Control Modes
). Control is the only mode where the
Product actively controls pressure. The setpoint value can be changed in any of
the three modes, but the Product is idle until
CONTROL
is touched.
Vent Mode
– When in Vent mode, all pressure on the test port is vented to
atmosphere.
Measure Mode
– When in Measure mode, the Product is holding pressure and
pressure control is idle. This mode provides a method to take a measurement
without control noise.
Set Target Pressure (Setpoint)
Target pressure or “Setpoint” is the numerical value of the pressure that the
Product controls when commanded. The Setpoint number can be entered into
the Setpoint field while in any of the operation modes (Measure, Control, and
Vent) however, the Product will not control pressure to the Setpoint unless it is in
Control mode. While in the Control mode, if a new Setpoint number is entered
and accepted, the Product immediately controls to the Setpoint. Once at the
Setpoint, the Product then uses the active Control mode to keep the pressure
between the upper and lower limits (see
Control Modes
).
Note
Jogging the pressure with the Jog Wheel adjusts the Setpoint value
in any mode but will only actively change the applied pressure while
in Control mode. See the subsequent section for more information
on jogging pressure.
To set a setpoint pressure:
1. Touch the setpoint field or push the
ENTER
button on the keypad to activate
the field.
2. Use the numeric keyboard to enter the number.
3. Push
ENTER
to accept. You do not need to touch
Clear
to enter a new value,
just key in the new value and it will overwrite the previous value. At any time,
touch outside the field to cancel the entry.
Step Pressure Up or Down
The pressure Setpoint can be changed with the Step function. The Step function
is used primarily when taking pressure steps in equal pressure increments and is
only available when in Control mode. The size of the pressure step is user-
defined. To step the pressure, enter a value for the step size and then use the up and
down arrows in the Main Display area to step that amount.
