Record the Greatest Disturbances

In this issue we look at the way that the Power Mater Series captures and organises data and helps you solve your power quality issues more quickly and easily. Read on to find out more about our Autoranking Waveform Capture of Greatest Disturbances and Extended Transients.

New Capture the Greatest Disturbances in Detail, Every Time

Troubleshooting power quality? Like looking for a needle in a haystack? When looking for sub cycle disturbances, traditional power quality analysers invite users to set thresholds, an action that requires ‘guessing’ what problem events you might see. If set too low, too much data is collected, if too high, nothing useful is captured. Waste of time!

Uniquely the PM7000 manages this recording of your disturbances with intelligence. We call this Autoranking Waveform Capture.

The PM7000 automatically records the worst-case waveform events and ranks them in order of severity – no need to set triggers. You can select how many disturbances you want to capture for up to seven types of event: transient, ring, notch, rise, fall and THD (Voltage) and Total Harmonics Current. The PM7000 fills up its allocated memory at the start of a recording with anything it sees, then discards the least interesting, as more exciting disturbances come along. No-rearming time means no data is missed and by the end of the recording you have the ‘greatest’, or if you would rather ‘worst’, events. See here how a captured disturbance led to solving a problem? Could this short lived transient have caused the voltage collapse which came 8 seconds later?

Voltage Transient

Voltage Transient

We can zoom in and see that the waveforms corresponding to the voltage transient have been captured, giving us a useful picture of what happened to the different Phases.

So the Outram Autoranking Waveform Capture System saves you time: no need to trawl through reams of data, you get what you want first time.

For more information about this feature please contact us at

Waveform Capture of Extended Transients

Although most transients and waveform events are over in less than three or four cycles, some events, such as the network’s recovery from sags after reclosures or the reaction of downstream control systems (wind turbine control), can persist for many seconds. In September we announced the Waveform Capture Extension, which enables recording of the waveforms for up to 60 seconds after a disturbance.

Extended Waveform Capture is available in the latest firmware release for the PM7000, which retains full backwards compatibility with previous revisions for all configurations. For more information please read our most recent press release.