Time resolution in Sags & Swells and Record modes

Fluke 43B

Users Manual

Time resolution in Sags & Swells and Record modes.

The modes Sags & Swells and Record basically perform similar functions. In both modes Fluke 43B plots a trend of up to two electrical parameters over time. In Sags & Swells mode the instrument plots voltage and current only. In Record mode the analyzer plots a wide variety of parameters, depending on the function that is active when the Record pushbutton is pressed. In both modes the instrument plots the parameters periodically over the so-called plot interval. Refer to the table below for the relationship between Recording Time and Plot Interval. The relationship is based on the fact that there are always 240 plots across the horizontal screen width.

Recording Time	Plot Interval	Recording Time	Plot Interval

4 minutes	1 second	8 hours	2 minutes

8 minutes	2 seconds	16 hours	4 minutes

16 minutes	4 seconds	24 hours	6 minutes

30 minutes	8 seconds	48 hours	12 minutes

1 hour	15 seconds	4 days	24 minutes

2 hours	30 seconds	8 days	48 minutes

4 hours	60 seconds	Endless (16 days)	1 to 96 minutes

Fluke 43B always measures faster than the plot interval: it always is looking at multiple measurements for each point that is plotted. In fact the analyzer looks at all the measurements it has taken during a plot interval and records a minimum, maximum, and average reading. The difference between Sags & Swells and Record mode is in the measuring rate.

Sags & Swells is optimized for measuring short duration variations of current and voltage. The rms current and voltage of every line cycle are measured. The Fluke 43B then records the min (lowest single cycle), max (highest single cycle), and average measurements at the end of each plot interval.

The Record mode takes measurements roughly 250 milliseconds apart. It also records the min, max, and average during each plot interval.