Test and Measurement Forum

Gaps in data

Forum for discussing PicoLog

Gaps in data

Postby David » Fri Nov 08, 2002 3:38 pm

I am getting gaps in my data when viewing the graph - Why?

Postby mark » Fri Nov 08, 2002 3:40 pm

PicoLog has 2 modes for collecting data, fast block and real time.

Fast Block
In fast block data can be collected at high speed but will not be plotted on the graph until after the data has been collected.

Real Time Continuous
Each time a sample is taken the graph is replotted. It takes a finite amount of time to plot the graph during which time the computer cannot collect any more data points. This is usually not a problem as the time taken to plot the graph is much smaller than the sampling time. There are however two possible cases where a problem may occur.

Case 1
The graph starts ok but gaps start to appear once you have collected a lot of data and the gaps get larger. This is because the time taken to plot the graph is dependant on the number of data points that need plotting. As the number of points increase the time taken to plot the graph will increase.

Case 2
You have a very fast sampling rate (eg 1mS) and the computer takes longer than 1mS to plot the graph.

The solution for both cases is the same.

If you do not need to view the graph during data collection then close it.
If you must have the graph open then you should adjust the graph plotting options as follows: -

1. Click the Graph Options "Tick" button

2. Change the "Update graph every 1 Samples" to every 10 or 100 samples

3. Click the OK button.

The graph will only be redrawn each time 10 or 100 new readings have been taken.

Return to PicoLog

Who is online

Users browsing this forum: No registered users and 1 guest