High Voltage Energy Monitoring with the Profile V

In most cases the Profile Portable Energy Recorder will be used to monitor energy use on three phase or single phase, low voltage circuits. However, high voltage energy monitoring surveys are also possible with the Profile V using the Two Wattmeter Method.

The guide below details how this can be done. Please note that this method is only possible with the Profile V monitor. The Profile IV can not be used to monitor high voltage circuits without manual alteration of survey data.
If you have a Profile IV Energy recorder and wish to perform high voltage energy monitoring surveys please contact NewFound Energy about upgrading your Profile.

What follows is intended as a brief guide only. Please see the Profile Installation Guide and the full Profile User Guide for more details as well as general installation and safety guidance.
It is assumed that the user is familiar with the basic operation of the Profile and that the Profile is set to automatic Current & Voltage ranging as will commonly be the case.

Throughout this guide where reference is made to cable phase colours, the new cable colouring is stated first with the old colour after it in italics.

Warning: Installing a Profile Portable Energy Recorder system can involve working near to exposed electricity carrying cables or bus bars and should therefore only be performed by a suitable person with the relevant electrical safety qualifications.

Profile Connections for High Voltage Energy Monitoring

Voltage Connections
Under the two wattmeter method the Profile should be powered and take its voltage reference via the 110V voltage transformer secondaries with connections as follows:

Profile Live connection to phase 1 (Brown/Red).
Profile Neutral connection to phase 2 (Black/Yellow).

These connections can be made via the optional mains (voltage probe) kit or by installation of a (temporary) 13A socket wired with the live connection to phase 1 (Brown/Red) and the neutral connection to phase 2 (Black/Yellow).

Illustration of High Voltage Energy Monitoring Two Wattmeter Method Connection

Illustration of High Voltage Energy Monitoring using the Two Wattmeter Method Connection

Warning: Never connect the PROFILE to voltages above 240 volts nominal, 268 volts RMS maximum. Connection to higher voltages will cause destructive protection to operate and may destroy the instrument completely.

N.B. Star and delta VT secondary connections:
a) The voltage transformer (VT) secondary wiring may be such that three VTs are wired as a star configuration with an earthed centre point or as two or three VTs wired in delta configuration .
The Profile assumes that the nominal VT secondary voltage line to line is 110 volts. If the nominal secondary voltage is different to 110 volts you will need to adjust the primary VT ratio setting to compensate;
e.g. if the VT ratio is 13,800/100 volts you must convert this to 15,180/110 (by multiplying 13,800 by 110/100) in order to set the primary HV voltage in the Profile correctly.

b) VT secondaries are normally wired with two VTs; Brown/Black, (Red/Yellow - phase1/phase2) and Grey/Black (Blue/Yellow - phase2/phase3) where the two phase 2 (Black, Yellow) ends are connected together to ground.
The Profile should be connected with its neutral input to Black (Yellow - phase 2) and live input to Brown (Red - phase 1).
If VTs are wired in a star configuration, the centre connection should be ignored. The voltage connections should still be made with the neutral input pin of the Profile connected to the Black (Yellow - phase 2) point and the live input connection to the Brown (Red - phase 1) voltage point.

Rogowski Current Coil Connections
When performing a high voltage energy monitoring survey using the two wattmeter method, only two current measurements are required. The Brown (Red - phase 1) & Grey (Blue - phase 3) coils should be used to measure the phase 1 & 3 currents respectively.

Brown (Red) coil measures phase 1 current.
Grey (Blue) coil measures phase 3 current.

The Rogowski coils should be connected to the Current Transformer (CT) secondaries.
It is important that the coils are fitted to the correct phases and with the current flow in the correct direction through the coil.

Rigid Rogowski coils  showing current flow direction

FlexiCoil orientation showing current flow direction

Profile coil orientation showing correct current flow direction

N.B. When measuring a 5 Amp CT secondary current it is important to note that a correctly wired and fitted CT has its secondary connected such that the current flow is in the direction P1 to P2 and the corresponding secondary is S1 to S2. Correct CT installation can not be guaranteed however, so installation should be checked where possible.

Profile Installation for HV Energy Monitoring Surveys

Once connections are fitted as above, the instructions below should be followed to instigate the high voltage energy survey and set the necessary parameters in the Profile.

1. When first powered, the Profile's LCD will show the mode of operation of the Profile e.g. '30 mins autologg', and the current date & time.

Profile 30 min autolog

2. To instigate recording press the return key;Profile Enter Key

The display will show 'Settling down please wait'. If this message does not appear, remove & return power to the Profile before re-trying.

Profile Settling Down, please wait

3. With a supply of 110 Volts, the Profile V will ask if it is connected to a HV circuit.
Select 'Yes' by pressing the up arrow [↑].

Profile HV Energy Monitoring - Is this HV?

4. The VT primary voltage must then be set.
The current setting is stated in the 'VT:...' row.
Use the up arrow [↑] and down arrow [↓] buttons to change the 'New:...' setting. Available options are 33000, 11000 & 6600 volts.
To confirm the new selection press the enter button: Profile Enter Key

Profile HV Energy Surveys VT Selection

5. Once the VT primary is set & confirmed ('VT: ...' & 'New: ...' will match), press the escape key: Profile Escape Key
a) If the current being measured is above 6 Amps, Profile will ask you to Phase by Hand (Autophasing is not possible with high voltage surveys).
Press the escape key again: Profile Escape Key
and continue to phase by hand.

b) If the current being measured is below 6 Amps, Profile will ask if the Rogowski coils are measuring a CT secondary.

Profile HV Surveys Phase by Hand

Profile HV Energy Monitoring CT Secondary

6. a) If the Profile is not measuring CT secondary currents; press the down arrow button [↓] to answer 'No'.
You will then be asked to phase by hand.
Press the escape key: Profile Escape Key
and continue to phase by hand.

a) Profile LCD Phase by Hand

6. b) If the Profile is measuring CT secondary currents; press the up arrow [↑] button to answer 'Yes'.
Then use the up arrow [↑] and down arrow [↓] buttons to set the CT primary.
Once set, press the enter button to confirm the new settingProfile Enter Key

b) Profile HV Energy Monitoring Set Current Transformer Primary Current

7. Once the CT ratio is set and confirmed (The displayed 'CT ratio...' should match the displayed 'New rtio...'.), press the escape key: Profile Escape Key
You will be asked to phase by hand.

Press the escape key again: Profile Escape Key
and continue to phase by hand.

Profile LCD Phase by Hand

Once successfully installed, the Profile system will record the energy use on the high voltage circuit to which it is connected.
When the survey is complete, data may be downloaded to a PC using the ProPower 3 software as detailed in the software documentation or by use of the Profile Data Download App for Android.

For permanent monitoring of energy use on high voltage circuits, high voltage electricity meters are available which can be connected to our AtlasEVO Energy Management System.

For more information on this, or any of our energy management, monitoring & control systems please contact NewFound Energy Ltd.