Maple Systems OIT Family - Manual (Page 96)

Function Key LEDs
Each global function key on the OIT3250, OIT4450 and OIT5400 has an associated
Function Key LED. Each of these LEDs can be controlled by a PLC coil or by an OIT
function key.
PLC Controlled
If a Function Key LED is programmed to be controlled by the PLC, then the LED reflects
the current value of a pre-programmed PLC coil. The OIT reads the coil once every
second. If the coil is set, the corresponding Function Key LED is turned on. If the coil is
clear, the corresponding Function Key LED is turned off.
OIT Controlled
If a Function Key LED is programmed to be controlled by the OIT, then it provides the OIT
operator with visual feedback on the status of the corresponding function key. The operation
of the Function Key LED varies based on the configuration of the function key. For more
information on function keys, refer to the Function Keys section in CHAPTER 6: Key Types.
Momentary Function Key LED Operation
The LED remains lit as long as the function key is pressed.
Latched Function Key LED Operation
The LED blinks momentarily whenever the function key is pressed.
Push On/Off Function Key LED Operation
The LED can be programmed to operate in one of the following four modes:
• On/Off — When the function key sets the coil, the LED is turned on. When the function
key clears the coil, the LED is turned off.
• Off/On — When the function key sets the coil, the LED is turned off. When the function
key clears the coil, the LED is turned on.
• Blink/Off — When the function key sets the coil, the LED blinks at a rate of two blinks per
second. When the function key clears the coil, the LED is turned off.
• Off/Blink — When the function key sets the coil, the LED is turned off. When the
function key clears the coil, the LED blinks at a rate of two blinks per second.
Using the LEDs 96
1010-0099, Rev. 07