Metering and Power Management | EFEN GmbH

Energy efficiency through measuring and monitoring

Measuring power parameters such as current, voltage and harmonics is a core competence of EFEN. This includes a comprehensive range of window- and tube-type current transformers. The range of high-grade devices in all rating classes allows complete installations to be equipped with components of one single system. For specific requirements, EFEN also offers a comprehensive range of wound primary current transformers, summation current transformers and transformers for NH fuse-links. EFEN’s current transformer blocks are easily and quickly integrated into E3 fuse-switches.
The integrated solutions from EFEN for electronic fuse monitoring offer convenient monitoring functions when plants need to be retrofitted.

Window-type and tube-type current transformers

EFEN offers a full range of window-type current transformers for primary currents up to 5,000 Amps as well as tube-type current transformers up to 600 Amps for line measuring or for NH fuse-switches. Current transformers are also available as PTB-compliant variants for billing purposes in accordance with the German Act on the Reorganization of Statutory Metrology and its adjustment to European legislation.
EFEN therefore has been offering PTB-compliant low-voltage current transformers according to module D or F since 2015.

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Special-purpose current transformers

For specific applications, EFEN has in store a great number of special-purpose current transformers. If you wish to achieve higher classes and performance levels at low ratios with window-type current transformers, we recommend the wound primary current transformers PSW 55 and PSW 70. Both comply with VDE 0414 T44-1 and IEC/EN 600-44-1.
Using EFEN summation current transformers of the PSS 2 and PGSU series allows up to ten supply outlets to be bundled into one power metering unit. Window-type and low-voltage current transformers for NH fuse-links complement EFEN’s system.

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Transformer blocks for E³-NH vertical design NH Fuse-Switches

The low-voltage current transformer blocks for E³ NH fuse-switches impress with both their features and performance characteristics. Thanks to their compact design, sizes 1 to 3 fit perfectly into the corresponding device openings. For secure contact, they are quickly and directly bolted to the output rails of E³ NH fuse-switches. This ensures accurate measuring results. Integrated 4-mm2 box clamps make sure that the secondary lines are properly connected. The E³ current transformer blocks in sizes 1 to 3 are available for all standard current levels.

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Plant availability is a prerequisite for production, growth and economic efficiency. Downtimes must be reduced to a minimum – no matter if power distribution grids, industrial plants or sources of renewable energy are concerned. Here, EFEN’s electronic fuse monitoring (ESÜ) offers a high level of transparency. Tripped fuses are immediately detected, allowing suitable remedial action right away. An end-to-end system for E³ NH fuse-switches with identical component width makes retrofitting existing installations quick and easy.

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