The logging seems to occur when [GUN 02 ENABLE DATA // B3:12/5] is 1.
[GUN 02 ENABLE DATA // B3:12/5] is latched, to 1 on a rising edge of [Start Trend GUN#02 // B3:13/0].
The rising edge of [GUN 02 ENABLE DATA // B3:12/5] triggers the copying of data,
ONCE (rising edge) to F8:6 and N11:49. The is the key to the answer to your question.
[GUN 02 ENABLE DATA // B3:12/5] becoming 1 also starts a 1500ms = 1.5s timer; at the expiry of that timer, [GUN 02 ENABLE DATA // B:12/5] is unlatched, to 0, which I assume will stop the logging.
It appears the logging occurs once per second: the two rows in the output file with the same value, 980, have different time stamps. Since those two rows occur one seconds apart, it is possible that they could occur during one 1.5s cycle of the timer.
E.g. say
- The start of logging is triggered at time-of-day 10:27:40,600 of the PV800.
- The current values are copied to F8:6 and N11:49, but only ONCE.
- The timer starts its 1500s timing
- B3:12/5 is latched to 1
- At the start of the next whole second, 10:26:41,000
- The timer .ACC value is 400, so it has not expired
- B3:12/5 is 1
- which triggers the PV800 to the values from F8:6 and N11:40
- At the start of the second whole second, 10:27:42,000
- the timer .ACC value is 1400, so the timer has not expired
- B3:12/5 is still 1
- which again triggers the PV800 to log the values from F8:6 and N11:40 a second time
- And those values have not changed
- At 10:27:42,100
- the timer .ACC value reaches 1500,
- so the timer expires and .DN becomes 1,
- so B3:12/5 is unlatched to 0