Powering reliable research

Louise Davis

Power quality specialist REO UK has refreshed REOVAR, a series of variable transformers that provide adjustable output voltages with a constant sinusoidal waveform. REOVAR is designed to eliminate high-frequency electrical interference in test and research facilities where it can lead to falsified results but where various output voltages are required.

Experiments conducted at test facilities and research institutions are based upon a number of controlled factors, both variable and constant. It is crucial that these can be accurately manipulated, which alters the power and voltage demands of applications and risks generating electromagnetic interference (EMI).

REOVAR combats this by offering high precision adjustment of voltages with a consistently clean sine output, preventing harmonics from being generated for a more reliable power supply. The line is manufactured in accordance with VDE 0552 and EN 61558-2-14 regulations.

The product is available in both single-phase and three-phase models, both of which offer a turn-to-turn voltage of approximately 0.7V. The single-phase transformers provide an output voltage of 0-230V or 0-260V, while the three-phase model outputs 3 x 0-400V or 3 x 0-450V. Each is available in two versions – one with autowindings and another with separate windings.

“Repeatability is an important underlying factor in the overall success of most test procedures,” explained Steve Hughes, managing director of REO UK. “In testing products to examine how components operate under specific voltages, it is crucial that adjustments are both accurate and repeatable. The REOVAR’s close-stepped adjustment intervals mean that the voltage can be tightly controlled and accurately monitored to ensure reliable results, while the constant current output prevents EMI problems.

“Harmonics and other interference not only lead to voltage fluctuations, but they can also lead to long-term damage to the affected electrical infrastructure. Eliminating this risk helps businesses to get a better return on investment (ROI) on their equipment.”

The output voltage of the REOVAR range can also be easily controlled with REO’s NLR 7000 electrical control unit. The device is used to electronically adjust the voltage or power of variable transformers, combining a number of control options such as AC and DC control and 10-30 percent voltage increases.