Rockwell Automation 2711E-ND1 Reference Manual PanelBuilder 1400e - Manual (Page 108)

102 Push Buttons
Publication 2711E-6.15 – November 1998
Configuring the Normally Closed Momentary (N/C) Button
Configure the button according to this table:
Field Meaning
Name Assign a name, up to 15 characters to document the object for
printed reports. This increases the application’s size by 1 byte
per character.
Button Type Specify a Normally Closed Momentary Push Button.
Function Key
(Keypad only) Specify which function key the operator must press to activate
this button.
Number of States Only two states are possible. The value of state 0 is fixed at 1;
the value of state 1 is fixed at 0. You cannot change the number
of states or their values.
Initial State The button’s initial state is fixed at 0. You cannot edit this value.
Control The Normally Closed Momentary Push Button uses the
following controls:
Button Control records the status of the button: 0 when the
button is pressed and 1 otherwise. You can assign only a tag to
this control.
The Push Button Hold Time, as selected in the Timing
Parameters tab of the Configure Terminal Setup dialog box,
ensures that the value at the control is held for at least the
specified duration.
Note: If you do not assign this control, an error state occurs
when the object is displayed on the PanelView terminal. The
button displays state 1 without its label, alerting the operator to
the error state.
Indicator State controls the display state of the object. You can
assign a tag or expression to this control.
If you assign only the Button Control and not the Indicator State
control, the button state is displayed as soon as the button is
pressed and released. The feedback for this control is local and
immediate. It does not necessarily reflect the Button Control’s
value.
If you assign the same tag to the Button Control and Indicator
State control, the terminal displays the button state based on
the Button Control value. The button displays state 1 when the
operator presses it, and displays state 0 when the operator
releases it. This is a more reliable way of configuring the button;
however, if DH+ or ControlNet network traffic is heavy, the
display response may be delayed.
To provide a visual handshake with the PLC, assign different
PLC addresses to the Button Control and Indicator State
control. Program the PLC to set the Indicator State control to
the value of the Button Control, and the button changes to the
state with that value.
If the Indicator State control value does not match any of the
state values, an error state occurs and the button displays state
1 without labels.
Because these controls use only two values, digital tags are
recommended.