Four output modes
AC, DC, AC+DC and DC+AC support different supply scenarios and combinations of alternating and direct voltage components in one instrument.
N78300 – Programmable AC Power Supply up to 25 kVA in 3U
For single- and three-phase AC testing with programmable harmonics and adjustable output impedance.
The N78300 combines programmable AC/DC power with user-defined waveforms in a 19-inch, 3U chassis. Up to 25 kVA in AC mode at 20–500 Hz supports demanding tests within limited rack space. Single-phase, three-phase and reverse-phase output configurations adapt the supply to different devices under test.
Controlled supply disturbances
Sequence, sweep and surge & sag functions reproduce changing supply conditions; switch-on and switch-off phase angles are programmable from 0–360°.
Harmonics up to order 50
At a 50/60 Hz fundamental, distorted waveforms can be generated and analysed, with individually adjustable harmonic amplitude and phase.
Digital integration
USB, CAN and LAN are standard. SCPI, Modbus-RTU and CANopen support integration into supervisory control and test workflows.
Personal project consultation
Do you need support selecting the right power supply? Our technical specialists will provide personal advice tailored to your application.
Select the appropriate technical configuration or access product documentation directly.
ART. NO.
Description
Current [A]
Power [P]
Voltage [V]
N78309-350-105
|
Description
N78309-350-105 Programmable AC/DC power supply, 9 kVA / 6 kW, AC 350 V L-N / 606 V L-L, DC ±500 V, ±105 A, 3U
|
Current [A]
105
|
Power [P]
9000
|
Voltage [V]
350
|
AC Quelle (1/3-ph)
N78312-350-105
|
Description
N78312-350-105 Programmable AC/DC power supply, 12 kVA / 12 kW, AC 350 V L-N / 606 V L-L, DC ±500 V, ±105 A, 3U
|
Current [A]
105
|
Power [P]
12000
|
Voltage [V]
350
|
AC Quelle (1/3-ph)
N78318-350-105
|
Description
N78318-350-105 Programmable AC/DC power supply, 18 kVA / 18 kW, AC 350 V L-N / 606 V L-L, DC ±500 V, ±105 A, 3U
|
Current [A]
105
|
Power [P]
18000
|
Voltage [V]
350
|
AC Quelle (1/3-ph)
N78325-350-105
|
Description
N78325-350-105 Programmable AC/DC power supply, 25 kVA / 25 kW, AC 350 V L-N / 606 V L-L, DC ±500 V, ±105 A, 3U
|
Current [A]
105
|
Power [P]
25000
|
Voltage [V]
350
|
AC Quelle (1/3-ph)
N78300 programmable AC/DC power supply overview
The N78300 series supplies devices under test with programmable AC or DC voltage and also supports AC+DC and DC+AC. Four models cover 9, 12, 18 and up to 25 kVA in single-phase or three-phase AC operation. Output voltage reaches 350 V AC phase-to-neutral, 606 V AC line-to-line in three-phase operation and 700 V AC in reverse-phase operation. A frequency range of 1–500 Hz supports testing at different supply frequencies. Sequence, sweep and surge & sag functions complement user-defined waveforms. These capabilities enable investigation of supply effects on chargers, power supplies, household appliances and avionics. All models use a 19-inch, 3U chassis with a 6.8-inch LCD. Selection requires joint consideration of output configuration, frequency, RMS and peak current, and the applicable AC, AC+DC or DC power limit.
Key benefits
Power within limited rack space
Up to 25 kVA AC at 20–500 Hz in 3U reduces the space required for the power supply in a test system.
Multiple supply scenarios
Four output modes and selectable phase configurations support tests on AC- and DC-powered components using the same instrument series.
Repeatable disturbance profiles
Sequences, frequency sweeps and voltage swells or sags create controlled changes in supply conditions for comparable test runs.
Reproduce waveform distortion
Individually adjustable harmonics and 30 preset distortion waveforms simplify investigation of DUT behaviour under non-sinusoidal supply conditions.
Adjustable output impedance
Programmable resistance and inductance enable investigation of supply effects at different output impedances.
Compensate lead voltage drops
Remote sense with up to 20 V compensation supports voltage delivery at the DUT terminals despite voltage drops along the connecting leads.
Operating principle and output configuration
In AC mode, voltage, frequency and phase are programmable. DC output and the combined AC+DC and DC+AC modes extend the available test scenarios. Single-phase, three-phase and reverse-phase operation have different voltage, current and power limits. Single-phase AC operation provides up to 105 A RMS and 315 A peak current; three-phase or reverse-phase operation provides up to 35 A RMS and 105 A peak per phase. Peak current is not a continuous current rating.
Power range and model selection
| Model | AC, single-/three-phase | AC, reverse-phase | AC+DC, single-/three-phase | AC+DC, reverse-phase | DC, single-phase | DC, reverse-phase |
|---|---|---|---|---|---|---|
| N78309-350-105 | 9 kVA | 6 kVA | 9 kVA | 6 kVA | 6 kW | 4 kW |
| N78312-350-105 | 12 kVA | 8 kVA | 12 kVA | 8 kVA | 12 kW | 8 kW |
| N78318-350-105 | 18 kVA | 12 kVA | 15 kVA | 10 kVA | 18 kW | 12 kW |
| N78325-350-105 | 25 kVA at 20–500 Hz; 21 kVA at 1–19.99 Hz | 16.6 kVA at 20–500 Hz; 14 kVA at 1–19.99 Hz | 15 kVA | 10 kVA | 25 kW | 16.6 kW |
Values apply to individual instruments. Three-phase AC power is the total output power, not the power per phase. Specifications are based on high-voltage input conditions; low-voltage input may reduce power and other operating limits. Maximum voltage, current and power are not automatically available simultaneously.
| Operating mode | Voltage range | Current limit |
|---|---|---|
| AC, single-phase | 0–350 V AC L–N | 105 A RMS; 315 A peak |
| AC, three-phase | 0–606 V AC L–L; up to 350 V AC L–N | 35 A RMS; 105 A peak per phase |
| AC, reverse-phase | 0–700 V AC between outputs | 35 A RMS; 105 A peak per phase |
| DC, single-phase | −500 to +500 V DC | −105 to +105 A DC |
| DC, reverse-phase | −1,000 to +1,000 V DC | −35 to +35 A DC |
Dynamics, resolution and signal quality
| Parameter | Value | Condition or meaning |
|---|---|---|
| Frequency setting | 1–500 Hz; resolution 0.001 Hz | Setting accuracy 0.01% |
| Voltage resolution | 0.01 V | AC and DC setting |
| Phase setting | 0–360°; resolution 0.01° | Programmable switch-on and switch-off phase |
| Dynamic response | 1 ms | DC operation with load capacitance ≤10 µF |
| Programming response | 5 ms | Separate specification from dynamic response |
| Total harmonic distortion | <0.5% at 1–100 Hz; <1% at 100.01–500 Hz | With a resistive load at full rated power |
Programmable functions
| Function | Operation and purpose |
|---|---|
| Sequence, sweep, surge & sag | Vary supply parameters within test workflows and investigate behaviour during voltage swells, voltage sags and frequency changes. |
| Waveform generation | Generate sine waves and user-defined triangle, sawtooth, square and trapezoidal waveforms for different supply scenarios. |
| Harmonics and inter-harmonics | Synthesise and analyse distorted waveforms. Harmonics up to the 50th order at a 50/60 Hz fundamental, with individually adjustable amplitude and phase. |
| Three-phase distortion | Single-phase, three-phase and unbalanced three-phase harmonic output; 30 preset distortion waveforms for quick recall. |
| Preset disturbance waveforms | Waveforms for tests associated with IEC 61000-4-11, -4-13, -4-14, -4-27 and -4-29. The specific test setup and parameter selection depend on the required test. |
| Programmable output impedance | Adjustable resistance and inductance: single-phase up to 333.333 mΩ and 333.333 µH, three-phase up to 1,000 mΩ and 1,000 µH, reverse-phase up to 2,000 mΩ and 2,000 µH. |
Typical applications
On-board chargers and charging infrastructure
Vary the AC input supply of chargers and charging stations. Programmable frequencies, voltage sags and distortion support investigation of supply effects.
Power supplies and household appliances
Test adapters, switching power supplies, LED drivers and household appliances at different supply voltages and frequencies; non-sinusoidal waveforms extend the test scenarios.
UPS and power electronics
Apply controlled changes to the input supply of UPS systems and variable frequency drives. Sequence and surge & sag functions support testing with disturbed supplies.
Aerospace and avionics
Test airborne equipment and aircraft electrical systems with an adjustable AC/DC supply. The frequency range up to 500 Hz also covers testing at 400 Hz.
Interfaces and automation
| Area | Equipment | Integration |
|---|---|---|
| Digital interfaces | USB, CAN and LAN as standard | Connection to supervisory controllers and test workflows |
| Communication protocols | SCPI, Modbus-RTU, CANopen | Define the protocol and physical interface together for the intended integration |
| GPIB | Optional | Include when configuring the instrument |
| Local operation | 6.8-inch LCD | Display of instrument and test information |
Power expansion
The series supports power expansion through parallel operation. The number of instruments, combination, wiring and achievable system power are defined for the individual setup.
Installation and infrastructure
| Parameter | Specification |
|---|---|
| AC input | Three-phase 340–480 V AC or 180–264 V AC; 47–63 Hz; input current ≤70 A in either range |
| Operating conditions | 0–40 °C; altitude <2,000 m; relative humidity 5–90%, non-condensing |
| Dimensions | 132 × 482 × 755 mm (H × W × D), including protective cover |
| Net weight | 42 kg |
| Remote sense | Maximum compensation voltage 20 V |
Allow for possible derating when operating in the low input-voltage range. Mains connection, cabling and protective devices must suit the selected setup.
Protection functions
Overvoltage, overcurrent, overpower and overtemperature protection (OVP, OCP, OPP and OTP) are provided. Limits and the protection concept must be matched to the DUT and test environment.
N78300 frequently asked questions
Which output modes are available?
AC, DC, AC+DC and DC+AC. Power limits depend on the model and selected output mode.
Is 25 kVA available across the entire frequency range?
For N78325-350-105, single-phase and three-phase AC ratings are 25 kVA at 20–500 Hz and 21 kVA at 1–19.99 Hz. The AC+DC limit is 15 kVA.
What is the difference between 350 V, 606 V and 700 V AC?
350 V is the phase-to-neutral voltage. 606 V applies line-to-line in three-phase operation, while 700 V applies between outputs in reverse-phase operation.
Can the series generate harmonics?
Yes. At a 50/60 Hz fundamental, harmonics up to the 50th order can be set with individual amplitude and phase; 30 preset distortion waveforms are available.
Are apparent power and DC power the same?
Treat these selection ratings separately: for example, N78309-350-105 provides 9 kVA AC and 6 kW DC in single-phase operation. The operating mode and permitted operating point determine selection.
Can voltage drops in connecting leads be compensated?
Remote sense supports a compensation voltage of up to 20 V. Connections and lead routing must suit the test setup.
Can the N78300 be used for on-board charger tests?
It can supply the AC input of an on-board charger and provide variable supply conditions, including voltage sags and waveform distortion.
Can UPS systems be tested under disturbed supply conditions?
Yes. UPS systems are an application of the series; surge & sag and sequence functions provide variable conditions at the input supply.
Are 400 Hz avionics tests possible?
400 Hz is within the 1–500 Hz output frequency range. Voltage, current, power and the required test profile must match the specific avionics application.
Technical consultation and project enquiry
Selecting an N78300 requires the output mode, phase configuration, voltage, frequency, RMS and peak current, and required power. Please also provide your disturbance profiles, interface requirements and available mains supply.
