GE 90-30/20/Micro manual Upctr

4

UPCTR

The Up Counter (UPCTR) function is used to count up to a designated value. The range is 0 to +32,767 counts. When the up counter reset is ON, the current value of the counter is reset to 0. Each time the enable input transitions from OFF to ON, the current value is incremented by 1. The current value can be incremented past the preset value PV. The output is ON whenever the current value is greater than or equal to the preset value.

The state of the UPCTR is retentive on power failure; no automatic initialization occurs at power- up.

_____

(enable)	(Q)
(reset) —R
(preset value) —PV

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(address)

Parameters:

Parameter			Description
address	The UPCTR uses three consecutive words (registers) of %R memory to store the
	following:
	•	Current value (CV)	= word 1.
	•	Preset value (PV)	= word 2.
	•	Control word	= word 3.
	When you enter an UPCTR, you must enter an address for the location of these
	three consecutive words (registers) directly below the graphic representing the
	function.
	Note: Do not use this address with another up counter, down counter, or any other
	instruction or improper operation will result.
	Caution: Overlapping references will result in erratic operation of the counter.
enable	On a positive transition of enable, the current count is incremented by one.
R	When R receives power flow, it resets the current value back to zero.
PV	PV is the value to copy into the counter’s preset value when the counter is enabled
	or reset.
Q	Output Q is energized when the current value is greater than or equal to the
	preset value.

4-20 Series 90-30/20/Micro Programmable Controllers Reference Manual–September 1998 GFK-0467K