Frequently Asked Questions- PM7000
The PM7000 is a top of the range, three phase power quality, harmonics, flicker and waveforms monitor
Click to view the PM7000 datasheet.
Having worked out the right hook-up to use, I'm struggling to get my wires hooked up in the right way to get correct recordings. Is there anything available to help me?
You can download our Hook-up Checklist which is available in European Union, American and Asian phase colors. We've included photos of what the logger and all the wires should look like as well as examples of vector diagrams and LED displays to give you confidence that you've hooked your analyzer up correctly.
It could also be the case that your wiring may not be what you're expecting. If you're convinced that you have hooked up the logger correctly take a look at the phase angle summary. Check that your phases are correct and that your CTs or Rogowski coils are facing in the right direction.
If you are using a rogowski coil, another thing you could do is to check that you have selected the correct current sensor on PMScreen. To do this go to 'Main menu', 'Configure', 'Input signals' (bottom of screen).
We normally try to sort out the voltages first and then, mindful of the load currently being measured, try to match up the currents. (Note motors offload may cause the current to lag the voltage significantly, by 50 ° or more.).
It might be a case of trial and error. Good Luck!
How do I set up Waveform Capture Extension?
Normally to set Waveform Capture Parameters you would do so on the screen shown to the right in PMScreens. To get here from the home screen click 'Main Menu', 'Configure', 'Waveform Capture'.In order to set Extended Waveform Capture(to allow recordings of the waveforms for up to 60secs) you need to go one step further. On this screen click on 'Set...' (bottom right hand corner).
Then you can select the extension you would like for each different type of event. E.g., click on 'Transient', then on 'Off/1638 evts' (this number may vary depending on memory allocation to Waveform capture).
This is the screen to set how long you want your extension to be. Typically this would be for 0.5 or 1 sec, rather than the whole 60 secs, as you limit the number of extension recordings, the longer you record the waveforms for.
If you click within the bar at '.5' to extend the green bar, it indicates that you can record 327 events with the extension.
Click 'Accept' and then try another, for example, by clicking on 'RMS Fall'. It then splits the total no. of waveforms collected between the two types of event.
Click on 'Off/819 evts' and extend the recording to 0.5 secs by clicking within the bar at '.5'.
In the bottom right hand corner you will then have the option (for RMS Fall and RMS Rise only) to 'Truncate extension on recovery from the fall'. Click on the green button ('Off') to switch it to 'On' if you'd like to. This means that the waveforms will stop recording when the Sag is over, therefore being economic with memory.
Click on 'Accept'. At this point you can continue with any other types of event or click 'Accept' again and you're back where you started.
Can I use PMScreens to check or change the settings in the PM7000 remotely via Ethernet? Also, is it possible to download the recorded session via Ethernet too?
Yes you can. The PM7000 Ethernet connection uses "COM port redirection". To configure this we have an in depth article on our knowledge base called 'Connecting to a PM7000 over an Ethernet network'. You can use this to set up your analyser.
Once configured you will be opening a port, for example COM6, and talking to the analyser using Pronto or PmScreen as if the analyser was directly connected. You can therefore change settings and download data as if you were in the room with it.
What do the LED colors on the top of the PM7000 correspond to?
The LEDs are used to show the status of each of the inputs, according to the hook-up (not counting the top right LED which shows that recording is taking place).
The 6 LEDs are in two columns of 3, Voltages on the left, currents on the right, with phases A,B,C corresponding to V1 V2, V3 from top to bottom.
Green = signal big enough to be measured, phase angle is good. Since the top left LED (V1 = Va) is used as the phase reference, this is always green while signal is present.
Orange = signal is big enough, but phase angle is suspect.
Red = signal is big enough, phase is reversed.
None = signal is turned off or is too small to give a meaningful phase measurement.
Thus if all signals are big enough and hooked up correctly so that all phases are correct, all the relevant LEDs will flash green. If one of the current sensors is reversed, the processor can detect that, and the corresponding LED will flash red. When the phase is neither good, nor reversed, that is when it will flash orange. So the orange means "It's not good enough, and it's not obviously reversed, so I don't know what it's supposed to be". The tolerance on phase is +/-30 deg.
If the phasor diagram on PMScreens says the connections are good, then the relevant LEDs will flash green. (The same phase angle measurements and decision making processes apply to both the LEDs and the PMScreens front screen.)
For more help on hooking up your PM7000 please use our PM7000 Hook-up Checklist in European Union, USA and Asian phase colors.
Where can you find the symmetrical component function on the PM7000? We have a negative sequence network, so when set up, we get an error message saying the PM7000 might not be connected correctly when we know it is.
If you think this is the reason for the error message then try swapping any two phases over. You should see NPS/PPS Unbalance of no more than a few %. NPS/PPS Unbalance can be seen on PMScreen on 'General Parameters / Live' and under the '3 phase AC power' functions. This is the one function which is sensitive to direction.
I can't seem to find my copy of the Product Manual anywhere. Where can I find it?
The Product Manual, the PM7000 Start Guide and the Hook-up Checklists are all available on the Pronto for Windows Software and Marketing CD included with your analyzer kit. If you no longer have this CD please contact us for the latest copy of the Product Manual.
How long does the PM7000 stay in 'discovery mode' for Bluetooth operations?
The PM7000 stays in 'discovery mode' for Bluetooth for 1hr. It is stimulated and woken up by lifting and closing the lid on the unit. The Bluetooth LED on the top panel will flash twice every 4 seconds to show that the Bluetooth is awake, then once connected that light will remain on. If the logger is on mains power or charger power the Bluetooth will stay on all the time.
Can I connect multiple PM7000s together across a site, so they all measure the same voltage inputs but different current inputs?
Yes, you can. In terms of placement we would recommend keeping the loggers close to the current sources and extending cables between the loggers and the voltage source.This is because you will be dealing with much smaller voltages through the CTs than through the PTs (remember the logger measures current by transforming it to voltage through the Rogowski coils or low current CTs). These small voltages will be more susceptible to common mode voltages that might be generated from any magnetic fields around your site. Since our voltage inputs are differential our common voltage rejection is good however we also recommend connecting the loggers via twisted cables (we recommend silicone coated) to reduce the potential for common voltage.
A distance of 10m along a cable should maintain relatively good readings but be aware that if you are increasing the length of interconnecting cables at all, the longer the connecting cables, the progressively worse the quality (noisiness) of your recording will get.
When measuring off a secondary VT at 110 volts, I have got a message saying that a fuse has gone on my PM7000. Why is this, how do I avoid it and how do I put in replacement fuses?
This may be due to a blown 325Amp fuse in the power supply board. The VT voltage is probably sourced from a relatively high impedence so when even a modest load like the PM7000 draws current it may take a while for the voltage to get to where it should be. If this is the case the current goes up and stays high for a period. The fuse rating is recommended by BSI which means we are not allowed to choose one with lots of margin and as fuses from the manufacturer are allowed a performance range, some may react and therefore 'blow' unnecessarily quickly if the higher current is prolonged.
Unfortunately the safety standards won't allow us to use a higher rated fuse so we now provide extra fuses in the kit for any eventuality while monitoring at lower voltage (110 volts).
The procedure for changing the fuses is found in the PM7000 manual or in the Knowledge Base in the article:Replacing the fuses in the PM7000.
Is the frequency measurement in the PM7000 derived from the V or I signal?
The PM7000 can track using any of V1, V2 or V3. V4 or the current channels are never used. The analyzer will use V1 unless V2 or V3 are more than twice as big. Also if the selected channel has less than (about) 4 volts rms then no frequency tracking is done, the PM7000 will keep running at the last known frequency.
This answer applies only to the PM7000, there are minor differences for the other products.
Click to view the PM7000 datasheet.
Having worked out the right hook-up to use, I'm struggling to get my wires hooked up in the right way to get correct recordings. Is there anything available to help me?
You can download our Hook-up Checklist which is available in European Union, American and Asian phase colors. We've included photos of what the logger and all the wires should look like as well as examples of vector diagrams and LED displays to give you confidence that you've hooked your analyzer up correctly.
It could also be the case that your wiring may not be what you're expecting. If you're convinced that you have hooked up the logger correctly take a look at the phase angle summary. Check that your phases are correct and that your CTs or Rogowski coils are facing in the right direction.
If you are using a rogowski coil, another thing you could do is to check that you have selected the correct current sensor on PMScreen. To do this go to 'Main menu', 'Configure', 'Input signals' (bottom of screen).
We normally try to sort out the voltages first and then, mindful of the load currently being measured, try to match up the currents. (Note motors offload may cause the current to lag the voltage significantly, by 50 ° or more.).
It might be a case of trial and error. Good Luck!
How do I set up Waveform Capture Extension?
Normally to set Waveform Capture Parameters you would do so on the screen shown to the right in PMScreens. To get here from the home screen click 'Main Menu', 'Configure', 'Waveform Capture'.In order to set Extended Waveform Capture(to allow recordings of the waveforms for up to 60secs) you need to go one step further. On this screen click on 'Set...' (bottom right hand corner).
Then you can select the extension you would like for each different type of event. E.g., click on 'Transient', then on 'Off/1638 evts' (this number may vary depending on memory allocation to Waveform capture).
This is the screen to set how long you want your extension to be. Typically this would be for 0.5 or 1 sec, rather than the whole 60 secs, as you limit the number of extension recordings, the longer you record the waveforms for.
If you click within the bar at '.5' to extend the green bar, it indicates that you can record 327 events with the extension.
Click 'Accept' and then try another, for example, by clicking on 'RMS Fall'. It then splits the total no. of waveforms collected between the two types of event.
Click on 'Off/819 evts' and extend the recording to 0.5 secs by clicking within the bar at '.5'.
In the bottom right hand corner you will then have the option (for RMS Fall and RMS Rise only) to 'Truncate extension on recovery from the fall'. Click on the green button ('Off') to switch it to 'On' if you'd like to. This means that the waveforms will stop recording when the Sag is over, therefore being economic with memory.
Click on 'Accept'. At this point you can continue with any other types of event or click 'Accept' again and you're back where you started.
Can I use PMScreens to check or change the settings in the PM7000 remotely via Ethernet? Also, is it possible to download the recorded session via Ethernet too?
Yes you can. The PM7000 Ethernet connection uses "COM port redirection". To configure this we have an in depth article on our knowledge base called 'Connecting to a PM7000 over an Ethernet network'. You can use this to set up your analyser.
Once configured you will be opening a port, for example COM6, and talking to the analyser using Pronto or PmScreen as if the analyser was directly connected. You can therefore change settings and download data as if you were in the room with it.
What do the LED colors on the top of the PM7000 correspond to?
The LEDs are used to show the status of each of the inputs, according to the hook-up (not counting the top right LED which shows that recording is taking place).
The 6 LEDs are in two columns of 3, Voltages on the left, currents on the right, with phases A,B,C corresponding to V1 V2, V3 from top to bottom.
Green = signal big enough to be measured, phase angle is good. Since the top left LED (V1 = Va) is used as the phase reference, this is always green while signal is present.
Orange = signal is big enough, but phase angle is suspect.
Red = signal is big enough, phase is reversed.
None = signal is turned off or is too small to give a meaningful phase measurement.
Thus if all signals are big enough and hooked up correctly so that all phases are correct, all the relevant LEDs will flash green. If one of the current sensors is reversed, the processor can detect that, and the corresponding LED will flash red. When the phase is neither good, nor reversed, that is when it will flash orange. So the orange means "It's not good enough, and it's not obviously reversed, so I don't know what it's supposed to be". The tolerance on phase is +/-30 deg.
If the phasor diagram on PMScreens says the connections are good, then the relevant LEDs will flash green. (The same phase angle measurements and decision making processes apply to both the LEDs and the PMScreens front screen.)
For more help on hooking up your PM7000 please use our PM7000 Hook-up Checklist in European Union, USA and Asian phase colors.
Where can you find the symmetrical component function on the PM7000? We have a negative sequence network, so when set up, we get an error message saying the PM7000 might not be connected correctly when we know it is.
If you think this is the reason for the error message then try swapping any two phases over. You should see NPS/PPS Unbalance of no more than a few %. NPS/PPS Unbalance can be seen on PMScreen on 'General Parameters / Live' and under the '3 phase AC power' functions. This is the one function which is sensitive to direction.
I can't seem to find my copy of the Product Manual anywhere. Where can I find it?
The Product Manual, the PM7000 Start Guide and the Hook-up Checklists are all available on the Pronto for Windows Software and Marketing CD included with your analyzer kit. If you no longer have this CD please contact us for the latest copy of the Product Manual.
How long does the PM7000 stay in 'discovery mode' for Bluetooth operations?
The PM7000 stays in 'discovery mode' for Bluetooth for 1hr. It is stimulated and woken up by lifting and closing the lid on the unit. The Bluetooth LED on the top panel will flash twice every 4 seconds to show that the Bluetooth is awake, then once connected that light will remain on. If the logger is on mains power or charger power the Bluetooth will stay on all the time.
Can I connect multiple PM7000s together across a site, so they all measure the same voltage inputs but different current inputs?
Yes, you can. In terms of placement we would recommend keeping the loggers close to the current sources and extending cables between the loggers and the voltage source.This is because you will be dealing with much smaller voltages through the CTs than through the PTs (remember the logger measures current by transforming it to voltage through the Rogowski coils or low current CTs). These small voltages will be more susceptible to common mode voltages that might be generated from any magnetic fields around your site. Since our voltage inputs are differential our common voltage rejection is good however we also recommend connecting the loggers via twisted cables (we recommend silicone coated) to reduce the potential for common voltage.
A distance of 10m along a cable should maintain relatively good readings but be aware that if you are increasing the length of interconnecting cables at all, the longer the connecting cables, the progressively worse the quality (noisiness) of your recording will get.
When measuring off a secondary VT at 110 volts, I have got a message saying that a fuse has gone on my PM7000. Why is this, how do I avoid it and how do I put in replacement fuses?
This may be due to a blown 325Amp fuse in the power supply board. The VT voltage is probably sourced from a relatively high impedence so when even a modest load like the PM7000 draws current it may take a while for the voltage to get to where it should be. If this is the case the current goes up and stays high for a period. The fuse rating is recommended by BSI which means we are not allowed to choose one with lots of margin and as fuses from the manufacturer are allowed a performance range, some may react and therefore 'blow' unnecessarily quickly if the higher current is prolonged.
Unfortunately the safety standards won't allow us to use a higher rated fuse so we now provide extra fuses in the kit for any eventuality while monitoring at lower voltage (110 volts).
The procedure for changing the fuses is found in the PM7000 manual or in the Knowledge Base in the article:Replacing the fuses in the PM7000.
Is the frequency measurement in the PM7000 derived from the V or I signal?
The PM7000 can track using any of V1, V2 or V3. V4 or the current channels are never used. The analyzer will use V1 unless V2 or V3 are more than twice as big. Also if the selected channel has less than (about) 4 volts rms then no frequency tracking is done, the PM7000 will keep running at the last known frequency.
This answer applies only to the PM7000, there are minor differences for the other products.
