Troubleshooting Power Quality Problems

The Power Master Series of analysers are often used to troubleshoot power quality problems. Our unique recording regimes make finding answers to questions like ‘What happened?’ and ‘Why?’ that much easier than with other power quality analysers.

Generally to get to the route of a power quality related problem it’s important to record the moment it happens in a high level of detail. This is all well and good if you know exactly when it’s going to happen but what if….

• You don’t know how big the power quality disturbance is going to be? Where should you set your thresholds?
  
  Ranger Power Master Analysers do not need any thesholds to be set. Disturbances and anomalies are automatically detected and recorded in more detail (down to a single cycle). No need to worry about recording too much or too little data by setting the thresholds too high or too low. This intelligent recording system makes pinpointing important sections of a power quality recording much more straightforward, just look for the sections recorded in more detail!
  The PM7000, PM70000FLM and the PM7503 can also automatically capture high speed waveforms of 7 types of event, again without setting any thresholds, ranking them in order of severity so you can quickly and easily pinpoint the most relevant in the recording using our software, Pronto.
  For more information please visit our pages on Single Cycle Adaptive Store and Auto-Ranking Waveform Capture or call us to allow us to explain further.
• You don’t know which channel or phase is going to give best indication of what the problem is?As well as recording 32 channels using the Adaptive Store mechanism mentioned above, the PM7000 (and other PM7000 derived instruments) records ‘General Parameters’ at the same time. General Parameters are >470 channels recorded automoatically every session at 1/2 cycle sampling with optional averaging times of 1 sec through to 2 hrs. If you think you’ve missed anything in the 32 detailed recording channels, the information you need will likely have been captured anyway. Just check your General Parameters.
• You don’t know when the offending disturbance is going to happen again?With all of our analysers, the user has the option of choosing to select FIFO mode (‘First In First Out’). If the disturbance you’re looking for doesn’t happen during your first recording, with FIFO selected you don’t have to restart your analyser, simply wait until it does happen then collect your data. The oldest data may have been erased to make way for the new, just make sure you return to pick up your analyser before the important data is erased to make way for new recordings! See below for more detail on our FIFO capability.
• You don’t know when you will be able to get back to site to turn your power quality recorder off?Using PMGateway with any of our Bluetooth enabled Power Quality Recorders or Fault Level Monitors allows you to have your recorded data sent directly to your email inbox. This saves huge amounts of time driving to and from sites collecting data. The recording analyser is interrogated by a Gateway Android phone which then downloads recorded data via Bluetooth then sends the data via email over either WIFI or a 3G/4G network. You can also start and stop the analyser simply by sending the Gateway phone, loaded with our PMGateway App an SMS text message!
• You don’t know where the problem is originating? I.e. If the relevant disturbances is coming from further up the network or from within the installation being measured?Single Cycle Adaptive Store records down to a single cycle, so as well as not having to set any thresholds, you can be confident, as long as you have not set the recording for too long, that you will be able to see the relevant disturbance in enough detail to work out where it has come from. If the voltage and current dip at the same time or if the current spikes as the voltage falls will indicate whether the problem has come from within or upstream of the installation being measured.

In a PM3000: In FIFO mode the recording process aims to use up about one quarter of the total store available in the logger on the current recording. This is normally the case, although in units with 32MB or 64MB internal memory, the max. space made available will be 4MB for each recording even if there is >16MB store remaining.

For example, if you choose to record for one day it will use up one quarter of the store for the first day. The logger will carry on recording the next day with a new session and use up another quarter of the store and so on for the third and fourth days. If you have not interrupted the process by now it will need to overwrite the first day on the fifth day. Whenever you retrieve your data you will collect the previous three and a bit days worth depending on when in the cycle you interrupt the process. This applies to any length of recording you set up. Adaptive FIFO storage allows you to record indefinitely, but you must retrieve your data soon after any significant event has occurred or the event may be overwritten. In units with 32MB or 64MB RAM, previous recordings will only be overwritten when the entire memory of the unit has been used up.

When setting up a recording in Point Store you will be invited on the screen to choose your desired record time and your sample rate. The screen will then show you the total time achievable using all the available store. This assessment by the logger will take into account the number of channels in use and the amount of store left. You may need to adjust either your preferred sample rate or record time or both if store is limited.

If the sample rate is set too fast for the desired record time and store available, the actual record time will necessarily be less than your desired time. If Point FIFO is activated, you can increase this actual record time indefinitely as storage space will be released as sessions are deleted. Note that each session time will be one quarter of the achievable record time.

 

For a more detailed explanation on our USB Memory Device Operations in the PM7000 and other aspects of our software visit our Knowledge Base .