LG Electronics 120S Power Supply / CPU Counter Processing, Up counter CTU, Down counter CTD

Chapter 5 Power Supply / CPU

5.3.6 Counter Processing

The counter counts the rising edges of pulses driving its input signal and counts once only when the input signal is switched from off to on. MASTER-K series have 4 counter instructions such as CTU, CTD, CTUD, and CTR. The followings shows brief information for counter operation. Refer to the ‘MASTER-K Instruction Manual’ for details.

1)Up counter (CTU)

-. The counter output relay is turned on when the current value reaches the preset value.

-. When the reset input is turned on, the counter output relay and current value is cleared as 0.

2)Down counter (CTD)

-. When the CPU is switched to the RUN mode, the current value is set as preset value. -. The current value is decreased by 1 with the rising edge of counter input signal.

-. The counter output relay is turned on when the current value reaches 0.

3)Up-down counter

-. The current value is increased with the rising edge of up-count input signal, and decreased with the rising edge of down-count input signal.

-. The counter output relay is turned on when the current value is equal or greater than the preset value otherwise off.

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