High Efficiency Transformers

ULLTRA High Performance transformers are designed to deliver more energy savings than any other transformer on the market. The result is a high performing transformer that offers the highest efficiency in the industry under either linear or non-linear loading and maintains these high efficiency levels at not only 35% loading, but over the entire load range.

While other energy efficient transformers on the market may meet new, more demanding standards such as NEMA Premium and CSL3, these standards only restrict losses under linear loading and at 35% load levels. When it comes to higher load levels and non-linear loading, other transformers on the market can’t offer the same high efficiencies under these conditions. ULLTRA High Performance transformers actually exceed NEMA Premium efficiency levels at their peak performance loading of 50%, thereby assuring the most energy savings under any loading.

ULLTRA High Performance Transformers offer quicker payback periods, and are engineered to perform. All ULLTRA Transformers are real-world tested in Mirus’ Harmonics & Energy Lab.


A perfect solution for any application where energy efficiency and lower life cycle costs are critical – K-12 and Higher Education, Government, Healthcare, Broadcasting, Commercial, Industrial and LEED buildings. Applications that expect heavier loads such as Data Centers, Solar and other Alternative Energy projects, will benefit from the ULLTRA Series Transformers' ability to maximize savings under ANY load and for ANY load profile.


ULLTRA™ - Ultra Low Loss Transformer

Optimized for any load level making ULLTRA the only transformer ideally suited for both light or heavy loading             conditions

Linear load losses are a full 30% lower than the already low levels defined by NEMA TP-1

Efficiencies meet NEMA Premium levels at the mandated 35% loading and even exceed these levels at the                 transformer’s peak design loading of 50%

Harmonic losses are also reduced to ensure efficiencies meet NEMA TP-1 requirements even under ‘real world’         non-linear loading

Inrush currents (< 8x rated) and audible noise (3dB lower than standard) are extremely low

Ideal for Solar Power or other applications where transformer loading varies widely and electricity rates are high


ULLTRA-H1E™ - Harmonic Mitigating Transformer

In applications where non-linear loading is expected to be severe, the ULLTRA-H1E combines the proven harmonic mitigating properties of Mirus’ Harmony™ HMT line with superior energy efficiency, low inrush, and low audible noise found in the ULLTRA design.

Voltage distortion (flat-topping) is minimized by cancelling zero sequence fluxes within the secondary windings           and eliminating circulating currents in the primary windings

Treats triplen harmonics (3rd and 9th) within the transformer and 5th and 7th upstream

The highest efficiency harmonic mitigating transformer from the company that first introduced HMT’s to the market       in the early 1990’s


Highest efficiencies in the industry at any load profile and at all load levels

Lowest 'Life Cycle Costs' for best paybacks and improved bottom line

Improves reliability by reducing voltage distortion

Exceeds CSL-3 and NEMA Premium requirements in a wider load range

Exceeds NEMA TP-1 efficiencies under non-linear loading

Energy savings are realized even during peak load conditions when environmental impact is greatest

Lower losses minimize energy waste and protect the environment by reducing greenhouse gas emissions

Contributes to LEED (Leadership in Energy Efficient Design) in Energy & Atmosphere and Innovation & Design           categories

Performance validated through linear and non-linear load testing in Mirus’ Harmonics & Energy Lab

Inrush magnetization currents are the lowest in the industry

Lower audible noise levels: 3dB to 5dB below NEMA ST-20 requirements



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