**White Papers:**

**D000120 – Why is fixed windowing bad practice for efficiency measurements?**Sample Windows in Asynchronous Efficiency measurements(White Paper) (PDF, 1.59MB)**D000123 – A high bit resolution does not mean higher accuracy, do you know why?**Analogue to Digital Converter (ADC) – Bit Count superstition(White Paper) (PDF, 663KB)

**Power Analysis Application Notes:**

**Can I use a DAQ card instead of a Power Analyzer?**APP037 – Do I need a power analyzer or can I use a DAQ card (PDF, 425KB)**RMS or Peak Ranging? Which is better for power analysis?**APP019 – RMS and Peak range considerations with Precision Power Analyzers (PDF, 175KB)**How do N4L compare to competitors with respect to wide band accuracy and calibration?**APP042 – Understanding High Accuracy Wideband Power (PDF, 492KB)**Are N4L Power Analyzers compliant to D0-160 and ABD0100 Avionics Standards?**APP040 – Power Analysis in Avionics – May 2020 (PDF, 189KB)**Is ISO17025 power calibration important to me?**APP038 – Understanding Power Calibration (PDF, 438KB)**How do I test a product to see if it complies with the standby power test standards such as EN50564 and IEC62301?**APP015 – Standby Power Measurement – IEC62301 (PDF, 2,183KB)**Can I measure Electric Vehicle Traction motor efficiency with the PPA?**APP032 – Efficiency Measurement of Traction Motors v2 May 2020 (PDF, 218KB)**How can I perform efficiency analysis using the Master/Slave dual instrument technique?**APP021 -Master Slave Effieicency testing (PDF, 160KB)**Can I analyze a motor during acceleration and deceleration?**APP025 – PWM Motor Drive Ramp Testing with the PPA45_5500 Power Analyzers (PDF, 153KB)**How do I perform AC-DC power efficiency measurements of power supplies using N4L PPA’s?**APP013 – AC – DC Efficiency Measurements with the PPA1520 (PDF, 255KB)**How do N4L achieve such accurate wideband current measurement?**APP012 – Current Shunt Field Cancellation (PDF, 590KB)**Can I use a PPA to measure 7 phase power?**APP036 – 6 & 7 phase motor drive analysis (PDF, 203KB)**The importance of Low Power Factor watts accuracy**APP035 – Low Power Factor Watts Measurement & Calibration (PDF, 228KB)**Why is the PPA so accurate at measuring harmonics?**APP030 – DFT or FFT – A Comparison of Fourier Transform Techniques (PDF, 372KB)**How do the N4L Power Analyzers avoid aliasing?**APP031 – Expanded Nyquist Sampling Theory – N4L (PDF, 44KB)**How does the PPA calculate the harmonic content of a waveform?**APP023 – Harmonic Analysis in Power Applications (PDF, 67.2KB)**PWM Motor Drive Theory**APP017 – PWM Motor Drives – Pulse Width Modulation Theory (PDF, 810KB)**How does 3 Phase 2 Wattmeter work, mathematically?**APP014 – 3 Phase 2 Wattmeter Explained (PDF, 663KB)**The mathematics behind calculated power accuracies at specified frequencies and phase angles**APP009 Power Accuracy (PDF, 64KB)

**IEC61000 Harmonics and Flicker ****Application Notes****:**

**A guide to IEC61000-3-3 and IEC61000-3-11**APP039 – A guide to compliant Flicker measurements – Are you fully compliant to IEC61000-3-3 and IEC61000-3-11 (PDF, 524KB)**Can I simulate flicker with an N4A Power Source?**APP034 – Flicker Simulation with the N4Axx AC Power Sources (PDF, 156KB)**How do N4L verify that the PPA55x1 is complaint to IEC61000-3-2 and IEC61000-3-3 (Harmonics and Flicker)?**APP028 – N4L Harmonics and Flicker Compliance Verification of PPA55xx to IEC61000-3-2, 3-3, 3-11 & 3-12 (PDF, 179KB)**A guide to flicker measurements**APP026 – IEC61000-3-3 2013 Electromagnetic Compatability – A Technical Guide to Flicker Measurement (PDF, 800KB)

**Frequency Response Analysis ****Application Notes:**

**How do I test loop stability of power supplies with the PSM series frequency response analyzers**APP002 Testing loop stability (PDF, 66KB)**How do I analyze the stability of a multiple loop closed feedback circuit?**APP010 Testing Switched Mode Power Supply Multiple Loop Gain (PDF, 23KB)**Can I measure PSRR (Power Supply Rejection Ratio) with the PSM series frequency response analyzers?**APP022 – PSRR – Power Supply Rejection Ratio Testing (PDF, 390KB)**How do I measure the frequency response (transfer function) of an amplifier?**APP020 – Amplifier Frequency Response (PDF, 160KB)**Testing RFI Line filters with the PSM series Frequency Response Analyzers**APP016 -Testing RFI Line Filters – Frequency Response Analysis (PDF, 759KB)**How to measure THD (harmonic analysis) with the PSM**App 007 Measuring low THD v2 (PDF, 90KB)**Measuring fluctuating signals with the PSM series**Measuring APP05 fluctuating signals (PDF, 16KB)**Testing frequency shift keying with the PSM**APP04 Testing FSK Communitation systems (PDF, 11KB)**Testing LVDT’s with the PSM**APP03 Testing LVDTs (PDF, 27KB)**Testing communications transformers with the PSM series**APP001 Testing communications transformers (PDF, 66KB)

**Electro-Chemical Impedance Spectroscopy ****Application Notes:**

**How do I perform EIS measurements of Electro-chemical cells and batteries with the PSM series?**APP033 – Battery Cell Electrochemical Impedance Spectroscopy iss3 Jan 2019 (PDF, 394KB)

**Impedance Analysis ****Application Notes:**

**Making Impedance measurements with a PSM**App 008 LCR Measurements v2**How do I measure the impedance of a capacitor with high DC voltage bias?**APP029 – Capacitor Impedance Measurements with High DC Voltage Biasing (PDF, 179KB)**How to measure LCR parameters at high frequencie**s APP011 Imp-at-high-freq Jan09 (PDF, 45KB)**How do I make high voltage capacitance measurements up to 800Vpk-pk?**APP006 High voltage capacitance measurement (PDF, 23KB)

**Power Transformer Testing ****Application Notes:**

**Is the SFRA45 compliant to IEC60076-18, the power transformer frequency response analysis test standard?**APP024 – Sweep Frequency Response Analysis of Power Transformers – Typical Test Sequences IEC60076-18 (PDF, 164KB)

**Can I measure power transformer efficiency with N4L PPA’s?**APP018 – Transformer Efficiency Testing and Transformer Vector Theory (PDF, 405KB)

**Videos:**

- Power Supply control loop frequency response testing

In this example, the PSM1700 is testing the closed loop stability of a switched mode power supply when connected to the control loop of the supply via an injection resistor and an N4L injection transformer. Control loop frequency response testing