UKAS ISO17025 Calibration Accreditation (Power)

UKAS_Logo N4L UKAS ISO17025 Power Calibration Certificate 2013

In 2013, Newtons4th UK was awarded Calibration Laboratory Accreditation by UKAS to ISO17025 for Voltage, Current, Power, Phase, Harmonics and Flicker. Our incentive to achieve this accreditation was a commitment to the highest level of metrology in our field of activity and the desire to provide a UKAS ISO17025 accredited calibration certificate with every new power analyzer we ship. This is a first in our industry and gives users of N4L power analyzers a higher level of standard certification than any other power analyzer manufacturer. A great amount of time and engineering effort has also been spent on implementing a sophisticated IEC61000-3-2, IEC61000-3-3, IEC61000-3-11 and IEC61000-3-12 harmonics and flicker calibration facility. This additional certification is also accredited to ISO17025, making N4L the first power analyzer manufacturer to offer power analyzer products with ISO17025 accredited certification to presently defined measurement criteria for IEC61000 Harmonic and Flicker standards.

ISO17025 UKAS Accreditation Schedule (Power Analyzers)
Signal Amplitude Frequency Range
Voltage Sine Amplitude 1V to 1008V 16Hz to 850Hz
Voltage Harmonic Amplitude 0V to 302V 16Hz to 6kHz
Current Sinewave Amplitude 100mA to 48A 16Hz to 850Hz
Current Harmonic Amplitude 0A to 15A 16Hz to 6kHz
Current to Voltage Phase Angle -180° to +180° 16Hz to 850Hz
Apparent Power (VA Product) 100mVA to 48.4kVA 16Hz to 850Hz
AC Power (Reference Source) 0W to 48.4kW 16Hz to 850Hz
AC Power (Calorimetry) (New for 2017) 1W to 5W 45Hz to 2MHz
Current Harmonic Amplitude to IEC61000-4-7 0A to 6A 16Hz to 6kHz
Flicker to IEC61000-4-15 Pinst (Sinusoidal Modulation) As Per IEC61000
Pinst (Rectangular Modulation)
Frequency Changes
Distorted Voltage with Multiple Zero Crossings
Harmonics with Sidebands
Phase Jumps
Rectangular Changes with Duty Cycle

N4L Calibration Philosophy

N4L products combine market leading accuracy with exceptional stability so that users can be confident in the long term integrity of measurements. While we recommend re-calibration every 12 months, stability over time and a conservative approach to our product specification allows our products to remain within specification for much longer periods of time. This is proven by many N4L customers who, working in accordance with their own ISO9001 procedures, are able to select 24 month calibration periods for N4L products they own.

Alongside our UKAS17025 certification which provides voltage, current, phase and power calibration up to 850Hz plus calorimetric power to 2MHz, we have developed a proprietary high frequency multi channel signal generator named the ACC-IV (Automatic Calibration Controller 4). Combined with custom designed amplifiers, the ACC-IV provides high frequency voltage and current sources at a higher signal level than commercially available calibrators and provides N4L with the means to calibrate our power analyzers over a wider frequency range than any other company.

The exceptional detail and accuracy of our calibration is achieved by unique calibration hardware, combined with processes that come from an absolute commitment to best metrology practice. This includes standard certification with over 200 calibration points at different levels and frequencies to the adjustment points we use for measurement optimization, therefore ensuring linearity of the instrument under test and also the integrity of calibration. An investment in 10 fully automated test systems allows N4L to provide this highest level of calibration with each and every power analyzer we supply.


Every power analyzer is supplied from new with two calibration certificates

1. ISO17025 UKAS accredited certification for Voltage, Current, Phase, Power (including low power for EN50564 and Energy Star) and PF up to 850 Hz.

2. Wideband Calibration certificate traceable to national standards covering up to 500kHz (PPA500), 1MHz (PPA1500/PPA3500) and 2MHz (PPA4500/PPA5500).

ACCIV Standard Calibration (Utilizing UKAS traceable instrumentation)
Signal Amplitude Frequency Range
Voltage Amplitude

+/-250uVpk to +/-400Vpk DC to 100kHz

Linearly reducing to +/-10Vpk 100kHz to 2MHz

DC to 2MHz
Current Amplitude

+/-1mApk to +/-5Apk DC to 100kHz

+/-300mApk to 100kHz to 2MHz

DC to 2MHz

Optional calibration:

1. ISO17025 UKAS accredited certification for Harmonics and Flicker in accordance with IEC61000-4-7/IEC61000-4-15

2. Customer specific calibration points can be offered as an additional option by request.

Our comprehensive calibration procedure is unrivalled in our sector* and we are confident that our power analyzers offer the highest wide bandwidth performance in the market.

*according to N4L research 2014

Relevant documentation:

pdf2 Technical Note 002 – Ranging Techniques and the Importance of Calibration PDF, 324kb

pdf2 Technical Note 003 – Closed Loop Calorimetry PDF, 2,418kb

pdf2 Schedule of Accreditation link: http://www.ukas.org/calibration/schedules/Actual/7949Calibration%20Single.pdf

pdf2 N4L Calibration Traceability Ladder link: N4L 17025 Calibration Traceability PDF, 492kb