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AC+DC Power Sources/Amplifiers

Programmable AC+DC Power Sources 3kVA ~ 67kVA (DC+0.01Hz ~ 1kHz)​

Customized Waveform Generation for High Power Applications

During research, development and testing of electronic products, the need to generate supply waveforms to power a product often fall outside the scope of the traditional mains supply. The wave forms required range from pure sinusoids at 120V 60Hz or even harmonically distorted with a specific harmonic making the THD contribution. In these cases, the N4A range of programmable AC power sources offer a flexible, rugged and high performance power generation solution. N4L provide best value programmable power sources on the market, achieving market leading fidelity performance  of <0.3% THD for sinusoidal wave form generation and unrivaled harmonic synthesis accuracy. Offering complete flexibility for a wide range of applications including white goods testing, motor drive development, EMC testing to IEC61000, aerospace, automotive, space exploration, robotics and much more. Our power sources feature the ability to generate complex as well as pure sinusoidal wave forms. If you need to generate customized high power wave forms, N4L will have a solution to meet your requirements.Industries such as automotive, aerospace, and renewable energy have embraced the N4A due to the fact they offer affordable, highly reliable, rugged, high performance AC+DC power delivery.

N4A03 3kVA Programmable AC+DC Power Source

What is an AC(+DC) Programmable Power Source?

An AC(+DC) Programmable Power Source can be summarized as a frequency converter with added functionality such as arbitrary waveform generation, voltage and frequency modulation capabilities and sequencing functionality. The arbitrary waveform generator is essentially connected to a high fidelity power amplifier able to deliver up to 67kVA (depending upon model).

How an AC(+DC) Power Source works

The N4A AC(+DC) power sources initially convert the AC input mains signal (Usually at 50/60Hz and between 100~250Vrms) into a DC signal, this is performed by a three phase or single phase input rectifier which charges a DC bus. The output of the DC bus is connected to a proprietary inverter which utilizes PWM switching techniques along with a carefully designed output filter network to provide a highly stable low distortion output waveform. Thus, if a sinusoidal output is required the distortion (% THD) is typically below 0.1%. The inverter is driven by a highly configurable arbitrary waveform generator, which is able to create complex wave forms that can feature a range of harmonics, interharmonics, surges, sags, swells and frequency variations required for both international standards compliance testing as well as customized in house development test procedures.

High Power Arbitrary Waveform Generation

All of our sources feature proprietary dual channel arbitrary waveform generator technology developed by N4L. This technology utilizes dual channel direct digital synthesis a summing amplifier circuitry to combine the two DDS generators. Thus, providing the user with simultaneous, multiple harmonic generation as well as frequency sweeping and long sequencing capabilities.

The use of two DDS generators provides optimized resolution of both the main power component and the modulation signal, whereby the modulation signal can be a harmonic or inter-harmonic of the fundamental, for example.

N4A03 3kVA Programmable AC+DC Power Source quarter view

This metrology permits long custom waveform sequences to be produced without a reduction in the resolution of each spectral component. This is especially beneficial when the harmonic is very small in comparison to the fundamental power signal. Traditional single DAQ arbitrary generators suffer from poor resolution when generating low level harmonics alongside large fundamentals. As a result of this technology, the accuracy of the N4A far exceeds the requirements of IEC61000-4-13 (harmonic and inter-harmonic susceptibility testing) and its competitors.

Create Custom Waveforms and Sequences

The N4A AC Source also features 10-bit vertical resolution and a maximum waveform resolution of 16,384 points to produce a single periodic waveform. There is also an internal storage function for imported custom wave forms featuring user intuitive library menus that display the waveform graphically on the user interface.

The N4A range of AC+DC Power Sources are available with a variety of output power ratings from 6kVA up to and above 30kVA. They are the perfect solution for general power source applications as well as IEC61000 electromagnetic compatibility standards testing, offering low THD and excellent reliability.

N4A AC+DC Power Sources – High Power, Low Distortion, 1kHz full signal bandwidth


Output Power


Output THD %

Output Phases

Maximum Output Current (Continuous)

Maximum Output Current (3 second inrush)


1kHz Full Signal,

15kHz Small Signal

<0.3%1 Phase10Arms20Arms
N4A1818kVA3 Phase (Optional 1 phase output)20Arms/phase40Arms/phase
N4A3030kVA3 Phase (Optional 1 phase output)32Arms/phase64Arms/phase
N4A6767kVA3 Phase75Arms/phase100Arms/phase

For more information please see the AC+DC Programmable Power Source product page

LPA Series Laboratory Power Amplifiers : Wide Bandwidth Precision Voltage and Current Amplifiers

The LPA range of Laboratory Power Amplifiers from N4L provide AC and DC coupled wide band amplification for a wide variety of industrial and laboratory applications. All LPA amplifiers exhibit a 1MHz bandwidth and range from 400Vpk, 50mA models to 18Vpk, 5Arms models.Designed originally for use with N4L Phase Sensitive Multimeters, they can also be used anywhere where there is a need to boost a signal in either voltage or current at frequencies up to 1MHz.They combine DC accuracy with wide bandwidth to faithfully reproduce complex wave forms, driving loads that may be resistive or reactive.Applications for which the LPA amplifiers can be used within are wide ranging, from Piezo transducer testing to materials analysis of dielectrics where high voltage DC offsets are required.The LPA can be coupled with an N4L PSM Frequency Response Analyzer and external current shunt to provide a flexible impedance measurement system able to drive DUT’s at higher voltages and currents normally possible using traditional LCR measurement methods.

LPA400 400V Laboratory Power Amplifier 400Vpk 1MHz

Reasons to choose an N4L Laboratory Power Amplifier

Unconditionally stable to any load Wideband
DC Accurate High performance to cost ratio

LPA AC+DC Wide-band Amplifiers – 1MHz bandwidth, up to 85VA




Slew Rate (Typical)

Output Coupling

Gain Options

LPA01Max +/-14Vpk, 700mArms1MHz600V/usac, ac+dc, ac+(dc)x1, x4, x10
LPA400A+/-400Vpk, 50mArms

100kHz @ 800Vpk-pk

1MHz @ 80Vpk-pk

350V/usx50, x200, x500
LPA400B+/-180Vpk, 100mArms

200kHz @ 360Vpk-pk

1MHz @ 80Vpk-pk

LPA05A+/-40Vpk, 3Arms

500kHz @ 80Vpk-pk

1MHz @ 40Vpk-pk

LPA05B+/-18Vpk, 5Arms1MHz