P-E-01—Procedures for calibrating and certifying electricity meter calibration consoles pursuant to EL-ENG-12-01—Requirements for the certification of measuring apparatus—electricity meter calibration consoles

6.0 Procedures for the assessment of technical requirements
(EL-ENG-12-01, s. 6.0) (part 1 of 2)

6.1 Use requirements (EL-ENG-12-01, s. 6.1)

6.1.1 Accuracy check (EL-ENG-12-01, s. 6.1.2)

6.1.1.1 Purpose

The purpose of section 6.1.2 of EL-ENG-12-01 is to ensure that a calibration console's accuracy is maintained during its period of certification. In order to provide assurance that a calibration console maintains its accuracy, a check is required every week that a console is used.

6.1.1.2 Guidelines
  1. The accuracy check is conducted by installing a check device that is expected to be a:
    1. certified standard,
    2. certified reference meter, or
    3. reference meter, where the accuracy is established using a certified calibration console to calibrate the reference meter in a MUT position and comparing the errors determined by the console with the known errors of the check device installed in the MUT position.
  2. The error determined above in (1) is to be within the tolerance set forth in section 6.1.2.5 (i.e. ± 0.1%) of EL-ENG-12-01.
  3. If a calibration console fails the accuracy check, it cannot be used until the cause of the change in error is found and corrected. In addition, any meters that were verified on the console since the last accuracy check will have to be reverified.
  4. An accuracy check is to be performed at least once a year for each test point identified on the certificate. If some of the test points have not been checked they are to be checked at the end of the year or the console certificate will not be renewed.

Note: The term "certified" implies traceability to the NRC.

6.1.1.3 Procedure for checking accuracy
  1. For each day the console was used during the week, review the records and select a test point from the list of test points used to verify meters. Additional test points may be included so as to ensure that all certified test points have been assessed at least once a year by an accuracy check. If all the test points have already been selected, the selection of test points for the accuracy check may be repeated.
  2. Use one of the check devices identified in 6.1.1.2 (1) above connected in the MUT position to energize the console at the test point selected.
  3. Execute a simulated verification test for the set up.
  4. Record the error determined by the console for the device installed in the MUT position.
  5. Correct the error of the check device by subtracting the known error of the console.
  6. Compare the corrected error of the check device obtained in step (5) with the know error of the check device. The results should be within the tolerance specified in section 6.1.2.5 of EL-ENG-12-01.

Note: Console owners are required to maintain records of the accuracy check, including the name of the operator who performed the accuracy checks.

6.2 Environmental requirements: temperature (EL-ENG-12-01, s. 6.2.1)

6.2.1 Purpose

The purpose of section 6.2.1 of EL-ENG-12-01 is to ensure that the temperature surrounding the console is within the requirement set out in section 6.2.1.1 of EL-ENG-12-01 while it is being calibrated. This procedure involves measuring the temperature surrounding the console.

6.2.2 Procedure for the assessment of temperature

  1. Place a calibrated thermometer within approximately 3 metres of the console.
  2. Record the temperature reading indicated on the thermometer once it is stabilized.
  3. Repeat the steps above during the calibration if the temperature is fluctuating to the extent that it may be outside the specified limits.

6.3 Mechanical requirements (EL-ENG-12-01, s. 6.3)

6.3.1 Grounding (EL-ENG-12-01, s. 6.3.3)

6.3.1.1 Guidelines
  1. Calibration consoles that are grounded shall be tested for proper grounding by taking voltage measurements between ground and all exposed metal panels while the console is energized to full voltage and minimum current.
  2. A properly grounded console is one that does not exhibit measured voltages greater than those stated in EL-ENG-12-01. In the case of consoles that are not grounded but protect the operator from a shock hazard by use of a ground fault interrupting (GFI) circuit breaker, a test shall be conducted to determine if the ground fault protection system operates as required.
6.3.1.2 Apparatus for consoles without automatic ground fault protection
  1. Voltmeter with low input impedance such as an electrodynamometer or moving coil voltmeter capable of measuring the full operating voltage of the console (electronic voltmeters may be unsuitable for this application as they may register floating/phantom voltages).
  2. Shorting bars for all MUT positions.
  3. Ohmmeter.
6.3.1.3 Procedure for consoles without automatic ground fault protection
  1. Place shorting bars in all MUT positions.
  2. Connect a long wire to the ground of the outlet that supplies the console and ensure the other end of the wire reaches the working area of the console.
  3. Ensure the console is de-energized.
  4. Use the ohmmeter, with one lead connected to the system ground, to check all the exposed metal panels, including screws, bolts, metal fasteners, switches, etc. All exposed metal panels should be electrically connected to ground (i.e. reading zero resistance).
  5. Energize the console to the highest test voltage and lowest test current used for verifying meters.
  6. Use the voltmeter, with one lead connected to the system ground, to check all the exposed metal panels, including screws, bolts, metal fasteners, switches, etc.
  7. Ensure the voltage between the exposed panels and system ground is within the limits stated in section 6.3.3.1 of EL-ENG-12-01.
  8. Record on the worksheet the maximum voltage measured in step (5) above.
6.3.1.4 Apparatus for consoles with automatic ground fault protection consisting of a ground fault interrupting circuit breaker that does not have a test function
  1. Shorting bars for all the MUT positions.
  2. Fuse holder complete with 0.5 Amp fuse (rated at 600 volt rms (root mean square)).
  3. Load resistor selected according to section 6.3.1.6(3).
  4. Test leads to connect the fuse and resistor in series between ground and the console supply conductor.
  5. Ammeter.
6.3.1.5 Procedure for consoles with automatic ground fault protection using the test switch
  1. Test consoles equipped with automatic ground fault protection consisting of a Canadian Standards Association (CSA)-approved GF circuit breaker with a test function shall be tested using the test switch.
  2. Energize the console to the highest test voltage and lowest test current used for verifying meters.
  3. Activate the GFI test switch.

Note: If the GFI circuit breaker does not trip, the console shall not be certified until a functional GFI circuit breaker is installed.

6.3.1.6 Procedure for consoles with automatic ground fault protection that do not have CSA-Approved test function
  1. Test consoles equipped with an automatic GFI that does not have a CSA-approved test function to ensure the breaker trips if the fault to ground exceeds 10mAmps.
  2. Measure the line voltage that supplies the console.
  3. Use the supply voltage to ground as a reference and calculate the size of resistor required to create a line to ground current of 10 mAmp. For a console with a supply voltage of 120 volts rms, the resistor is calculated as follows:

    A = 12 000 ohms. Perform a test to verify that the generated current is 10 ±1 mAmp. Connect a 0.5 Amp (600 volt rated) fuse in series with the resistor during all tests.

  4. Ensure the console is de-energized at the circuit breaker that supplies the console.
  5. Connect the resistor between ground and one of the supply conductors at the console, using a 0.5 Amp fuse connected in series with the resistor. The fuse and resistor must both be rated for a voltage exceeding the console supply voltage.
  6. Switch on the circuit breaker supplying the console.
  7. Energize the console to the highest test voltage and lowest test current used for verifying meters.
  8. Repeat steps (3) to (7) for each supply conductor (excluding ground) which enters the console.

Note: If the GFI circuit breaker does not trip during steps (6) or (7), the console shall not be certified until a functional GFI circuit breaker is installed.

6.3.1.7 Additional grounding procedure
  1. If any voltage is measured while performing the test of section 6.3.1.3 above, a second test should be performed with a low impedance moving coil type voltmeter to ensure the voltage measured is not a floating/phantom voltage.
  2. Complete the sections related to grounding in the worksheets.

6.3.2 Isolation from ground (EL-ENG-12-01, s. 6.3.4.1)

6.3.2.1 Guidelines

This test is performed by measuring the leakage current between ground and all live terminals on a calibration console. The console is energized to full voltage and current during this test. Conformance of a calibration console to the isolation requirements reduces the risk of shock hazard to an operator during normal use of the console.

6.3.2.2 Apparatus
  1. Milliamp meter capable of reading from 100 microamps to 1.0 Amp.
  2. Voltmeter with low input impedance such as an electrodynamometer or moving coil voltmeter. If this device is unavailable, a digital electronic voltmeter may be used.
  3. Resistors (as determined in 6.3.2.3(15) below).
  4. Ohmmeter.
  5. Shorting bars for all the MUT positions. The shorting bars must be of a type that will allow access to the current and voltage terminals to perform the test.
6.3.2.3 Procedure for testing isolation from ground
  1. If the console is to be used for testing single-phase and polyphase meters, setup the console in the configuration used for polyphase socket meter connections.
  2. If the console is to be used for testing single-phase meters only, setup the console in the configuration used for single-phase socket meter connections.
  3. Plug a long wire with a banana plug at one end into the ground socket of any wall electrical outlet of the same ground potential as the outlet that supplies the console. The banana plug may have to be splayed out to ensure that it stays in the socket. The other end of the wire should reach the working area at the console.
  4. Ensure the console is de-energized.
  5. Use the ohmmeter, with one lead connected to the system ground and check all possible live voltage and current terminals. All terminals should be electrically isolated from ground (i.e. reading infinite resistance).
  6. Place shorting bars in all MUT positions.
  7. Energize the console to its full operating voltage and full steady state current.
  8. Use the electromechanical voltmeter, with one lead connected to the system ground, to check if there is any voltage between any of the live terminals and ground. The voltage measured between any live terminal and ground should be essentially zero. If this is the case, proceed to step (9). If there is a measurable voltage between any live terminal and ground, a high leakage current may be present and step (9) must not be carried out. Proceed with steps (15) to (20) instead.
  9. Select the highest current range on the mAmp meter and connect one lead to the system ground wire. Take measurements at all live terminals to determine if there is any leakage current from the terminal to ground. If there is no measurable current with the mAmp meter set to its highest current range, reduce the range until a current measurement can be read.
  10. De-energize the console and record the results in the Isolation section of the worksheets.
  11. Energize the console to its full operating voltage and the lowest test current used for verifying meters. When loading transformers are used and manually selected, perform this test using the highest voltage tap for the loading transformer to provide the lowest test current.
  12. Repeat steps (8) to (10).
  13. Perform steps (14) to (21) if the console makes use of multiple potential transformers during normal single-phase meter testing
  14. Energize the console to the highest voltage to be used with multiple potential transformers.
  15. Repeat steps (8) to (10) for all the multiple potential transformer terminals. If voltage was measured in step (8), perform steps (16) to (21).
  16. Record the voltage measured and determine a value for a test resistor based on the following formula
    R(test−reisistor) = V(measured) ÷ 0.002
  17. Ensure that the resistor is of sufficient wattage by applying the formula:
    W=I Squared × R

    where,

    • I = 2 mAmp, and
    • R = the test resistor value calculated in step (15) above
  18. De-energize the console and apply the resistor between ground and the test terminal. Re-energize the console and measure the voltage across the resistor. If the measured voltage is still present, the console is considered to be improperly isolated and no further tests should be performed.
  19. If the voltage has dropped to a lesser value than initially measured, de-energize the console and install the ammeter in series with the resistor.
  20. Measure the current flow through the resistor. If the current is 1 mAmp or greater,the console is not isolated. If the current is less than 1 mAmp, and the voltage level is greater than 30 Volts rms, the console is considered not to be isolated.
  21. De-energize the console and remove the resistor.
6.3.2.4 Remarks

No further testing or calibration shall be performed on a console that fails section 6.3.4.1 of EL-ENG-12-01.

6.3.3 Isolation of secondary circuits from primary circuits (EL-ENG-12-01, s. 6.3.4.2)

6.3.3.1 Guidelines

This test is performed by measuring the voltage between the voltage supply circuits to the console and the secondary voltage and current circuits of the console. If no voltage is measured, the calibration console is deemed to have the primary supply circuits isolated from the secondary metering circuits and meets the requirements of EL-ENG-12-01.

6.3.3.2 Apparatus
  1. Voltmeter with low input impedance such as an electrodynamometer or moving coil voltmeter. An electronic voltmeter is unsuitable for this application, as it will register floating/phantom voltages.
  2. Shorting bars for all the MUT positions.
  3. Long leads need to be used for making connections to the voltmeter from the primary supply to the test console metering circuits.
6.3.3.3 Procedure for the isolation of secondary circuits from primary circuits
  1. Review the calibration console schematic drawings prior to attempting this procedure to determine safe access to the appropriate voltage connections and switches.
  2. Remove the panels from the back of the calibration console or open the supply switch to access the voltage terminals, as required.
  3. If the console is used for testing single-phase and polyphase meters, set up the console in the configuration used for polyphase meter connections.
  4. If the console is to be used for testing single-phase meters only, set up the console in the configuration used for single-phase meter connections.
  5. Install shorting bars in all the MUT positions. Set the current selector switch or console configuration to enable current to flow in series with the shorting bars installed in the MUT positions.
  6. Ensure the proper safety equipment is used for performing this test. Rubber gloves and safety glasses need to be used when obtaining voltage readings.
  7. Set the voltmeter to the highest voltage range setting.
  8. Measure the voltage from each phase to ground and each phase to phase of the calibration supply to determine its correct configuration.
  9. If the calibration console supply configuration is three-phase three-wire delta, verify whether any of the phases are grounded. If one of the phases is grounded, stop any further testing until the safety hazard is corrected.
  10. Place shorting bars in all the MUT positions.
  11. Connect one lead of the electromechanical voltmeter to one phase of the supply.
  12. Connect the second lead of the electromechanical voltmeter to each of the different voltage and current terminals of the calibration console's metering test circuits.
  13. Energize the console to the highest voltage rating and test current.
  14. Verify that no voltage is present between the voltage supply and the live voltage and current terminals of the calibration console.
  15. Repeat the test for the other phases of the calibration console's supply voltage.
  16. Repeat the test if the calibration console is equipped with multiple potential transformers.
  17. Connect and energize the multiple potential transformers in the metering test circuits and ensure no voltage is present between the primary voltage supply and the secondary voltage terminals of the multiple potential transformers.
  18. Indicate on the worksheets if the calibration console primary supply circuits are isolated from the secondary test circuits.
6.3.3.4 Remarks

It may be convenient to combine testing the isolation from ground with verifying whether the primary supply circuits are isolated from the console metering test circuits, if all the conditions of the isolation from ground procedure can be met.

6.3.4 Meter mounting arrangements (EL-ENG-12-01, s. 6.3.5)

6.3.4.1 Apparatus
  1. Angle gauge block calibrated by the manufacturer.
  2. Inclinometer to serve as an indicator of the degree of levelness.
  3. Meter base from any socket-based meter. From a meter base of any socket-based meter, fashion a device that can be inserted into the calibration console sockets and that will present a surface upon which the digital inclinometer can be placed to determine both the side-to-side and the front-to-back level. This resting surface is to be representative of the disc of an intact meter when installed in the socket.
6.3.4.2 Calibration of inclinometers
  1. Locate a level surface. Establish that the surface is level by measuring its incline with the inclinometer.
  2. Turn the inclinometer 180 degrees about its vertical axis and measure the incline again. The surface may be considered level if both readings are within 1.5 degrees.
  3. Place the 1.0 degree angle gauge block on the level surface with the inclinometer on top of it.
  4. Record the inclinometer indication.
  5. Rotate the gauge block 180 degrees and place the inclinometer on top of the gauge block again.
  6. Record the inclinometer indication again. The error of the inclinometer at 1.0 degree has now been established.
6.3.4.3 Procedure for the assessment of meter mounting arrangements
  1. Ensure that the calibration console is de-energized.
  2. Place the device fashioned from the socket-based meter base into the socket.
  3. Place the inclinometer on the device and measure the side-to-side and front-to-back slope.
  4. Determine if the socket is compliant with the requirements of EL-ENG-12-01.
  5. Repeat steps (1) through (4) for the other sockets.
6.3.4.4 Remarks

Calibration of bottom-connected meter mounting arrangements is not required for socket adapters.

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