Current instrument transformers for indoor applications at medium voltage

GIS current transformers

GIS indoor CT

GIS 12 and GIS 24 are narrow design block-type current transformers, with support function, used in indoor applications for measuring and protection equipment, available in multi-core versions up to maximum 5 cores, with primary and secondary reconnection.

Several models are available for 12kV: GIS12d, GIS12e, GIS12f; or for 24kV: GIS24d, GIS24e, GIS24f.

 

Specifically designed versions as wideband transformers, with extended frequency range, were developed for applications in the field of power quality.

The transformer with extended frequency range is optimized for measurements up to 9 kHz and is used in 20 kV medium voltage networks.

In addition to permanent monitoring of power quality parameters (e.g. harmonics limit values, THD) at grid connection points (EN 50160), the use for permanent monitoring of non-linear operating equipment is also feasible.

GI current transformers

GI indoor CT

GI 30 and GI 36 are block-type current transformers, with support function, used in indoor applications for measuring and protection equipment, available in multi-core versions up to max 5 cores, with primary and secondary reconnection.

Voltage instrument transformers for indoor applications at medium voltage

GSES voltage transformers

GSES indoor VT

GSES 12D and GSES 24D are narrow design block-type voltage transformers, single-pole insulated, used in indoor applications for measurement and protection equipment, available for 12 kV or 17,5 kV (GSES12D) and 24 kV (GSES24D).

 

Specifically designed versions as wideband transformers, with extended frequency range, were developed for applications in the field of power quality.

The transformer with extended frequency range is optimized for measurements up to 9 kHz and is used in 20 kV medium voltage networks.

In addition to permanent monitoring of power quality parameters (e.g. harmonics limit values, THD) at grid connection points (EN 50160), the use for permanent monitoring of non-linear operating equipment is also feasible.

GSE voltage transformers

GSE indoor VT

GSE 10, GSE 20, GSE 30 and GSE 45 are block-type voltage transformers, single-pole insulated, used in indoor applications for measurement and protection equipment.

GSZS voltage transformers

GSZS indoor VT

GSZS 12 (6...11 kV) and GSZS 24 (13,8...20 kV) are narrow design block-type voltage transformers, double-pole insulated, used in indoor applications for measurement and protection equipment.

GZ voltage transformers

GZ indoor VT

GZ 12, GZ 24 and GZ 36 are block-type voltage transformers, double-pole insulated, used in indoor applications as voltage supply transformers for auxiliary services.

Current instrument transformers for outdoor applications at medium voltage

GIFS current transformers

GIFS outdoor CT

GIFS outdoor support type current transformers are used for metering and/or protection purposes in medium voltage grids with rated voltages of either 12, 17.5, 24 or 36 kV and rated current up to 1250 A.

Versions with primary reconnection are also available up to 2 x 300 A.

GIF current transformers

GIF outdoor CT

GIF outdoor support type current transformers are used for metering and/or protection purposes in medium voltage grids with rated voltages of either 10, 17.5, 20, 30, 36, 52 or 72,5 kV and rated current up to 3000 A.

Versions with primary reconnection are also available up to 2 x 600 A.

Voltage instrument transformers for outdoor applications at medium voltage

GEF voltage transformers

GEF Outdoor VT

GEF 12 | 17,5 | 24 | 36 | 40,5 are outdoor voltage transformers, single-pole insulated, used for measurement and protection equipment.

The secondary terminals are housed in a robust terminal box which can be sealed in the case of revenue metering.

VZF voltage transformers

VZF Outdoor VT

VZF 12 | 17,5 | 24 | 36 are outdoor voltage transformers, double-pole insulated, used for measurement and protection equipment.

The secondary terminals are housed in a robust terminal box which can be sealed in the case of revenue metering.

Current and/or voltage metal-clad instrument transformers for medium voltage

GBW metal-clad current transformers

GBW Metal-clad CT

GBW 12 | 24 | 36 are current transformers casted with epoxy resin and covered with a grounded metal enclosure, suitable for indoor applications.

The medium voltage end of the primary winding is provided with an inner cone for a cable connection with plug-in termination.

GBEI and GBEA metal-clad voltage transformers

GBE Metal-clad VT

GBEA and GBEI are metal-clad voltage transformers, single pole insulated, casted with epoxy resin for indoor applications. The resin body is covered with a grounded metal enclosure.

The medium voltage end of the primary winding can be provided with either an outer cone (GBEA) or an inner cone (GBEI) for a cable connection with plug-in termination.

These instrument transformers are suitable for installation inside or outside of switchgear having up to the highest voltage for equipment of 40,5 kV and accordingly, several versions are available: GBEIC 12/0, 24/0; GBEIN 12/0, 24/0; GBEAC 12/0, 24/0; GBEAN 12/0, 24/0; GBEI 36; GBEA 36.

KGBEI and KGBEA metal-clad combined (current and voltage) transformers

KGBE Metal-clad CT+VT

KGBEI / KGBEA 12 | 24 | 36 are indoor combined transformer with single-pole voltage and current transformer sections, fully encapsulated in epoxy resin and completely enclosed in a grounded metal enclosure.

The medium voltage connection is designed as an inside cone (KGBEI) or an outside cone (KGBEA) for a cable connection with plug-in termination.

Bushing type current transformers for indoor applications at medium voltage

GDS current transformers

GDS indoor bushing CT

GDS 12 | 17,5 | 24 | 36 are bushing type current transformers, fully encapsulated in epoxy resin, designed for indoor applications up to 36 kV and having rated primary currents between 150 A to 3000 A.

GTDS(O) current transformers

GTDS indoor bushing CT

GTDS(O) 10 | 20 | 30 are bushing type current transformers, with busbar (GTDS) or with round passage (GTDSO), fully encapsulated in epoxy resin, designed for indoor applications up to 36 kV and having rated primary currents between 800 A to 10000 A.

GSS(O) current transformers

GSS(O) indoor core CT

GSS(O) 10 and GSS(O) 20 are support type current transformers, with busbar (GSS) or with round passage (GSSO), fully encapsulated in epoxy resin, designed for indoor applications up to 24 kV and having rated primary currents between 50 A to 5000 A.

Toroidal current transformers including split-core design

IGE current transformers

IGE indoor core CT.pdf

IGE 0,5 B | 0,5 C | 0,5 CO are ring core current transformers, fully encapsulated in epoxy resin, used for measuring and protection equipment in indoor applications, available with various inner diameters and having the following rated current ranges according to the models: IGE 0,5 b: 30 ... 1500 A; IGE 0,5 c: 100 ... 3000 A; IGE 0,5 co: 100 ... 5000 A.

KSOH current transformers

KSOH indoor core CT

KSOH single-phase ring core current transformers are designed for sliding or plugging onto the insulated cable in the switchgear and are intended for digital protection devices for conventional protection and measurement purposes.

Several models are available: KSOH 1555C / KSOH 1555H / KSOH 1555O / KSOH 2212 / KSOH 1911.

KSOH1555: primary current 50 ... 1250 A, secondary current 1A (or 5A); on request two current values (e.g. 300 - 150 A) by means of secondary reconnection.

KSOH2212: primary current 50 ... 2500A, secondary current 1A (or 5A); on request two current values (e.g. 300 - 150A) by means of secondary reconnection.

UGSS(F) and RKU(F) current transformers

UGSS and RKU core CT

UGSS and RKU are split-core type current transformers used for indoor applications, to reliably detect the magnetic field of the small residual earth fault currents. The two segments of the split-core type current transformers are cast in resin while the core interfaces are lapped, creating a perfect magnetic connection.

UGSSF and RKUF are versions of split-core type current transformers designed to be used in outdoor applications.

The split-core type current transformers are a suitable solution for retrofit mounting around already installed cables with mounted terminations.

Damping unit against ferro resonance oscillations

The ferro resonance oscillations occur, if unipolar voltage transformers are forced to periodic saturation by switching operations and as a result, an overheating of their primary coil takes places and this leads to an internal flash-over that completely destroys the respective voltage transformers.

The damping units against ferro resonance oscillations DE 4, DE 6 and DE 9, consisting of a resistor group and a damping coil, can be selected based on the thermal limiting current as follows:

► for 4 A use the DE 4 with the damping coil ZKSWD 100 and resistor group with the internal resistance of 90 ohm;

► for 6 A use the DE 6 with the damping coil ZKSWD 300 and resistor group with the internal resistance of 90 ohm;

► for 9 A use the DE 9 with the damping coil ZKSWD 800 and resistor group with the internal resistance of 90 ohm.

Due to the slightly different phase position of the resistor group and the damping coil, it is guaranteed that the limiting currents 4 A, 6 A and 9 A are not exceeded. Of course, the mentioned damping coils are also individually available.