The EL+ vHF series was developed for demanding avionics applications and offers a feedback-capable, bidirectional load platform for the precise simulation of high-frequency power grids in the 360-900 Hz range. This allows linear and non-linear loads as well as grid-connected devices to be tested realistically - energy-efficiently, safely and reproducibly.
General features
- Bidirectional & regenerative: energy consumption and feed-in with high efficiency and low energy requirements.
- Clean mains input: THDi < 3 % and power factor > 0.98 at rated power.
- HF operation 360-900 Hz: optimized for 400 Hz on-board electrical systems and variable frequency systems.
- Power range: five models from 15 kW to 50 kW, can be connected in parallel for higher power.
- Fine-tuned control: precise control, harmonic generation up to 50th order, independent phase control.
- Flexible operating modes: constant current (CC), constant power/apparent power (CP/CS), impedance (CZ), interference and profile tests with high dynamics.
- Intuitive operation: 4.3" touch, Modbus TCP/Ethernet, optional analog/digital interfaces, LabVIEW-compatible.
- Master/slave operation: up to eight units can be combined, with automatic power and phase distribution.
- Safety functions: emergency stop, interlock, freely configurable protection and warning parameters.
The devices in the EL+ vHF series are ideal for testing aircraft power generators with variable frequency, simulating onboard loads (linear/non-linear), characterizing network-coupled converters and performing disturbance profile tests, flicker analyses and power qualifications in avionics systems.
Model in focus: EL+20 vHF
The EL+20 vHF represents the next performance level within the series and combines a compact design with higher current and power capability. It is the preferred choice for laboratory and test applications where slightly more power reserve than the 15 kW model is required - for example for avionics load tests in medium power classes or for modular master/slave setups.
Power data & suitability
- Nominal power: 20 kW
- Nominal AC current (rms): 26 A (3-channel) / 78 A (1-channel)
- Dimensions (W×D×H): 450 × 770 × 1100 mm
- Weight: approx. 165 kg
- HF range: 360-900 Hz (identical for all models)
Comparison within the series
Compared to the smaller EL+15 vHF, the EL+20 vHF offers more power and performance while retaining the same functions, frequency range and user interface. Compared to the larger variants EL+30 vHF (27 kW), EL+40 vHF (40 kW) and EL+50 vHF (50 kW), it is positioned as a balanced mid-range model with an ideal ratio of power, efficiency and portability.
- Advantages: compact, powerful, cost-efficient for medium avionics load tests up to 20 kW.
- Identical platform: same RF characteristics, same control modes and power quality as all models in the series.
- Scalable: easy to combine in a master/slave network for higher outputs.
Product features of the series:
- Mains side (input): 3×400 Vrms + N + PE, voltage range +15 % / -20 %, 48-62 Hz
- Mains quality: THDi < 3 % at rated power, power factor > 0.98
- Efficiency (typ.): ≥ 91 %
- Output (HF-AC, EUT side): 1- or 3-phase operation; permissible voltage up to ±400 Vpk; approx. 35-277 Vrms ph-N / 35-480 Vrms ph-ph; option "HV" up to approx. 295/510 Vrms
- Frequency range (HF): 360-900 Hz
- Operating modes: CC, CP, CS, CZ, Steps, Disturbance profiles
- Dynamics: rise times in the millisecond range, setpoint resolution up to 10 mA/1 W
- Harmonics: up to 50th order, freely programmable per phase
- . order, freely programmable per phase
- Phase configuration: independent parameters per phase (amplitude, phase angle, harmonic content)
- Overload capacity: up to 125 %/10 min, 150 %/1 min, 200 %/2 s
- Operation & interfaces: 4.3" touch, Modbus TCP/Ethernet, optional RS485/CAN/RS232 gateways; analog/digital I/Os
- Master/Slave: network of up to 8 devices via fiber optics (AC parallel, DC parallel/serial)
- Safety & measurement: Emergency stop, interlock, alarms, measured values (U/I/P rms, frequency, temperature, data logging)
- Environment: 5-40 °C, up to 95 % r. H. (non-condensing), forced ventilation
- Noise level: < 52 dB(A)
- Dimensions/Weight: approx. 450 × 770 × 1100 mm, ~165 kg (depending on model)
- Standards & certifications: CE, EN-50178/EN-62040-1 (safety), EN-62040-2 (EMC), RoHS
