VT1005 AC/DC High Voltage Divider

• very high measurement accuracy
• up to 5000 V in the DC - 4 MHz range
• typical application -> measuring the efficiency of inverters (especially those using SiC technology), while measuring the power at their output must not neglect the RF component
• in contrast to conventional differential probes, the VT1005 has a very flat characteristic over the entire frequency range, which guarantees stability and accuracy of the resulting measurement of inverter efficiency:

  

• The advantage over the significantly more affordable voltage transformers is then the ability to measure not only pure sine waveforms, but also PWM, i.e. signal waveforms deformed in various ways. This is made possible by a unique feature of HIOKI analyzers, which enables automatic phase shift correction in cooperation with dedicated HIOKI current sensors.

Detailed Product Overview

The HIOKI VT1005 is a high-precision AC/DC high-voltage divider for measuring signals up to 5 kVrms. It scales input voltage by a fixed 1000:1 ratio and outputs a clean, scaled-down signal via BNC for direct connection to power analyzers, memory recorders, oscilloscopes, or any other instrument with a BNC input.

The VT1005 delivers outstanding accuracy across a wide frequency range: ±0.08% for DC and ±0.04% at 50/60 Hz, with amplitude flatness of ±0.1% up to 200 kHz and phase accuracy of ±0.1° up to 500 kHz. This wide and flat frequency response enables precise power analysis even in fast-switching systems with significant harmonic content, supporting measurements up to 4 MHz (–3 dB).

Comparison of an AC/DC high voltage divider with differential probes 

Compared to traditional high-voltage differential probes, the HIOKI VT1005 High Voltage Divider delivers clear performance advantages. Most differential probes offer around 2% amplitude accuracy and typically do not specify phase accuracy. These features make them unsuitable for precise power measurement, particularly in systems deploying Pulse Width Modulation (PWM), such as high voltage DC/DC converters and traction drive inverters. The VT1005 is engineered for high-accuracy AC/DC voltage measurement with well-defined phase and amplitude specifications, making it the right choice for such demanding applications.

Passive architecture for stable measurement results

The passive architecture of the VT1005 eliminates issues commonly associated with active differential probes, such as probe loading, thermal drift, and active circuit noise. This results in cleaner signals, higher measurement accuracy and long-term stability, even at higher frequencies.

The VT1005 also features a high common-mode rejection ratio of 80 dB at 100 kHz, allowing it to maintain measurement integrity even in electromagnetically noisy environments such as inverter test benches or industrial power systems.

Thanks to its accuracy, frequency response, and noise immunity, the VT1005 is an essential tool for measuring losses in high-voltage transformers and inductors, evaluating the efficiency of SiC/GaN-based power electronics, and qualifying wireless power transfer (WPT) systems.