Current Transformers
Measuring current transformers are designed to proportionally convert alternating current for subsequent measurement in 50 Hz networks with a rated voltage of up to and including 0.66 or 1 kV. The transformers are used in commercial electricity metering circuits (current transformers for active-energy meters) for billing consumers, as well as in measurement and protection circuits.
Unlike a voltage transformer, a measuring current transformer must not be operated with an open secondary circuit, as the voltage across the secondary winding can rise to a dangerously high level.
A current transformer is a step-down transformer designed to convert a high current to a value suitable for measurement.
Current transformers are manufactured primarily using toroidal cores, as this reduces measurement errors associated with leakage inductance.
Serial production and custom manufacturing of current transformers
LLC «YuKON RU» manufactures:
Designed for installation in 100 mm-wide feeders (PPVR) as an import-substitution product for commercial electricity metering.
Can be used at any facility as an alternative to busbar current transformers (for busbars up to 30 mm wide), especially where installation space is limited or the distance between adjacent phase busbars is at least 15 mm (when installed on phase B with an offset relative to phases A and C) or at least 30 mm (when installed in a row).
The main electrical and metrological characteristics of the compact TShP-0.66m busbar current transformers are shown in the following table:
| Characteristic | Value |
| Rated voltage, kV | 0,66 |
| Highest operating voltage, kV | 0,72 |
| Rated secondary current, A | 5 |
| Rated frequency, Hz | 50 |
| Rated primary current, A | 30; 40; 50; 60; 75; 80; 100; 150; 200; 250; 300; 400; 500; 600; 750; 800 |
| Rated secondary burden (cos φ=1), VA | 0.5; 1; 2; 2,5; 5 |
| Rated secondary burden (cos φ=0.8), VA | 3; 5; 10; 15; 20; 25; 30 |
| Accuracy class | 0,2S; 0,5S; 0,5 |
Mounting TShP-0.66m transformers to a cable or busbar using a clamping screw or cable tie.
Designed for proportional conversion of alternating current for subsequent measurement in AC circuits with a rated frequency of 50 Hz and a rated operating voltage of 0.66 kV.
The transformer is secured to the primary conductor using the mounting kit, attached to the base via mounting feet, and/or installed on a DIN 35 rail using an adapter.
Mounting the TShP-0.66m transformer on a 35 mm DIN rail using an adapter (not included).
The transformers consist of a toroidal magnetic core and a multi-turn winding housed in an enclosure made of flame-retardant thermoplastic with a PV-0 flammability rating in accordance with GOST 28157. The winding leads are connected to paired terminals located on the transformer housing.
By design, these are busbar-type transformers with a single transformation stage, one transformation ratio, and one secondary winding. The primary winding is formed by the busbar or cable of the switchgear into which the transformer is installed. Busbar dimensions: 30 × 5 mm and 30 × 10 mm.
The transformer operates by converting primary-winding currents into secondary-winding currents. All transformers are step-down transformers.
The transformers retain their accuracy class when the secondary load is reduced, including down to zero.
The hinged transparent cover protects the secondary winding terminals and the transformer nameplate. The cover can be sealed to prevent unauthorized access.
Appearance and overall dimensions of the TShP-0.66m30.
Appearance and overall dimensions of the TShP-0.66m40.
Appearance and overall dimensions of the TShP-0.66m50.
Cross-reference table for equivalent compact busbar current transformers.
| Brand | Country | Model | Length, mm |
Width (including mounting lugs), mm |
Height, mm |
Busbar Size, mm | Accuracy Class | Rated Primary Current Range, A |
| YUKON RU (Yudzhen) | Belarus | TShP-0.66 M30 | 60 | 30 (50) | 83 | 30 × 10, 20 × 10, 25 × 10 | 0.5; 0.5S; 0.2S | 60-800 |
| Belarus | TShP-0.66 M40 | 60 | 40 (60) | 83 | 0.5; 0.5S; 0.2S | 50-800 | ||
| Belarus | TShP-0.66 M50 | 60 | 50(70) | 83 | 0.5; 0.5S; 0.2S | 50-800 | ||
| CIRCUTOR | Spain | TCH 6 | 64 | 44(60.5) | 80.5 | 10 × 20, 10 × 30, 40 × 10 | 3; 1; 0.5; 0.2; 0.5S; 0.2S | 150-800 |
| TCH 6.2 | 64 | 44 (60.5) | 80.5 | 10 × 20, 30 × 10 | 3; 1; 0.5; 0.2; 0.5S; 0.2S | 50-600 | ||
| EFEN | Germany | PSA 313 | 60 | 30 (44) | 78 | 30 × 10 | 1; 0.5 | 100-600 |
| PSA 113 | 49.5 | 30 (44) | 70 | 30 × 10 | 1; 0.5 | 60-600 | ||
| PSA 315, EPSA 315 | 60 | 55 (69) | 85 | 30 × 10 | 1; 0.5; 0.2; 0.5S | 75-600 | ||
| PSA 115 | 49.5 | 50(64) | 70 | 30 × 10 | 1; 0.5 | 50-600 | ||
| FRER | Italy | TAC03 | 56 | 45 (63) | 85 | 32 × 10 | 3; 1; 0.5; 0.2; 0.5S; 0.2S | 40-600 |
| ABB | Germany | CT3 | 58 | 44 | 97 | 30 × 10, 20 × 10 | 3; 1; 0.5 | 50-600 |
| Germany | CT4 | 75 | 44 | 109 | 30 × 10, 20 × 10, 40 × 10 | 1; 0.5 | 10-1000 | |
| DEKraft | China | TShP-0.66-30 0.5 | 60 | 37 | 79 | 30 × 10 | 0.5 | 30-300 |
| SACI | Spain | TU-30 | 60 | 36 (51.5) | 79 | 30 × 10 | 3; 1; 0.5 | 100-600 |
| Phoenix Contact | Germany | PACT MCR-V2-3015-60 | 60 | 30 | 80 | 30 × 15, 20 × 20 | 1; 0.5 | 60-750 |
| Schneider Electric | France | METSECT5MA0xxR | 56 | 63 | 80 | 30 × 10 | 1; 0.5 | 150-400 |
| MBSAG | Germany | EASK 31.3 | 61 | 35 (48) | 75.5 | 30 × 10, 20 × 10 × 2 | 0.5; 0.2; 0.5S | 100-750 |
| EASK 31.4 | 61 | 45 (58) | 78.5 | 30 × 10, 20 × 10 × 2 | 0.5S | 100-750 | ||
| ASK 31.3 | 61 | 35 (48) | 75.5 | 30 × 10, 20 × 10 × 2 | 1; 0.5; 0.2S | 50-750 | ||
| Ritz Instrument Transformers GmbH | Germany | KS60-03 | 60 | 30 (44), 40 (54), 50 (64) | 85 | 30 × 10, 30 × 12, 25 × 15, 20 × 18 | 3; 1; 0.5; 0.2; 0.5S; 0.2S | 50-750 |
Since 2014, YUKON RU LLC has been actively supplying various customers, including competitors, with components and semi-finished products for assembling current transformers—metrologically certified measuring coils manufactured to fit the dimensions of customers’ housings and casting molds.
The company has two high-performance SA507 comparator-based systems—among the most advanced equipment currently available—for calibrating instrument current transformers (ICTs) and measuring coils. This capacity enables the calibration of tens of thousands of such devices per month.
The main technical capabilities of the SA507 system for calibrating current-transformer coils and instrument current transformers (ICTs) are shown in the following table:
| Characteristic | Value |
| Rated primary current, A | 0,5; 1; 1,25; 1,5; 2; 2,5; 3; 4; 5; 6; 7,5; 10; 12,5; 15; 20; 25; 30; 40; 50; 60; 75; 80; 100; 125; 135; 150; 175; 200; 250; 300; 350; 400; 500; 600; 750; 800; 1000; 1200; 1250; 1500; 1600; 1800; 2000; 2400; 2500; 3000; 3200; 3500; 4000; 5000 |
| Rated secondary current, A | 5 |
| Rated secondary burden (cos φ = 1 or cos φ = 0.8), VA | 0,5; 0,75; 0,8; 1; 1,25; 1,5; 1,75; 1,875; 2; 2,5; 3; 3,75; 4; 5; 6; 7,5; 10; 11,25; 12,5; 15; 20; 25; 30; 40; 45; 50 |
| Accuracy class | 0,1; 0,2; 0,2S; 0,5; 0,5S; 1; 3; 5; 10; 5P; 10P |
To date, hundreds of variants of these products have been developed, with different ratings and accuracy classes and with toroidal or rectangular cores. Accordingly, the company has extensive experience in designing them.
These measuring coils are supplied to partners in Italy, Poland, Kazakhstan, and Belarus. To date, shipment volumes for these products have reached tens to hundreds of thousands of units.
Our company is ready to promptly design and manufacture custom coils for instrument current transformers according to your requirements.
They were developed in 2012 to meet special requirements for a major Russian project involving the modernization of commercial electricity metering systems at multi-story residential buildings in the Moscow region.
They differ from competing products by featuring a large housing opening for installation on insulated cables with a diameter of up to 52 mm, while retaining compact overall width and thickness. They can be installed on cables crimped with KN 240 cable lugs or smaller, including up to two cables, each crimped with its own cable lug of up to and including KN 240 size.
The innovative design enables quick and cost-effective installation directly on the cable using a nylon cable tie and a single bolted connection in the primary circuit. Compared with busbar and support-type current transformers, this product offers enhanced protection against electricity theft because there is no additional connection in the primary current circuit.
The main technical specifications of the TPP and TPP-N bushing-type instrument current transformers are provided in the following table:
| Specification |
Value |
| Rated voltage, kV | 0.66 or 1.0 |
| Highest operating voltage, kV | 0.72 or 1.2 |
| Rated secondary current, A | 5 |
| Rated frequency, Hz | 50 |
| Rated primary current, A | 50; 60; 75; 80; 100; 150; 200; 250; 300; 400; 500; 600; 750; 800; 1000; 1200; 1500; 1600; 2000 |
| Rated secondary burden (cos φ=1), VA | 0.5; 1; 2; 2,5; 5 |
| Rated secondary burden (cos φ=0.8), VA | 3; 5; 10 |
| Accuracy class | 0,2S; 0,5S; 0,5 |
At the end of 2018, TPP and TPP-N window-type instrument current transformers, equipped with a pair of PKFL 745532.103 universal inserts for a 30×5 mm busbar, were fully approved and recommended by MKS, a branch of PJSC Rosseti Moscow Region, for installation on the outgoing feeders of the ShchRNV switchboard assembly with ABB and Jean Müller fuse blocks, in accordance with technical solution SEK421736.065.TRP, as replacements for imported compact 60–62 mm-wide current transformers manufactured by Circutor and MBS AG.
30×5 mm busbar installation option using a universal insert that can be mounted in eight positions.
Fastening the TPP and TPP-N transformer to a cable using a clamping screw or cable tie.
Fastening the TPP and TPP-N transformer to a busbar using a cable tie or clamping screw.
Transformer mounting option using the PKFL 753731.001 clamping bracket.
TOP-N-0.66 current transformers are designed to transmit measurement signals to measuring instruments. They are used in electrical energy measurement and metering circuits in 50 Hz AC installations with a rated voltage of 0.66 kV.
Main technical specifications of TOP-N-0.66 support-type transformers:
| Characteristic | Value |
| Rated voltage, kV | 0,66 |
| Highest operating voltage, kV | 0,72 |
| Rated secondary current, A | 5 |
| Rated frequency, Hz | 50 |
| Rated primary current, A | 1; 5; 10; 15; 20; 25; 30; 40; 50; 60; 75; 80; 100; 150; 200; 250; 300; 400 |
| Rated secondary burden (cos φ=1), VA | 1; 2,5 |
| Rated secondary burden (cos φ=0.8), VA | 5 |
| Accuracy class | 0.2S; 0.2; 0.5S; 0.5; 1; 3; 5 |
The transformer complies with GOST 7746-2015, GOST IEC 60044-1-2012, and TU BY 300220471.002-2011. The housing components are made of flame-retardant plastic. The warranty period is 5 years. The calibration interval in the Republic of Belarus is no more than 8 years.
The magnetic cores of TOP-N-0.66 support-type instrument current transformers are also made of a nanocrystalline alloy and offer the following advantages over current transformers with electrical-steel cores:
– resistance of metrological characteristics to DC magnetization;
– improved energy efficiency of commercial metering (lower losses) due to the material’s higher electrical resistance and reduced core magnetization-reversal losses;
– long service life while maintaining metrological characteristics.
The nanocrystalline-alloy magnetic core ensures long-term parameter stability for more than 25 years.
Gabaritnye razmery transformatora TOP-N-0,66.
Mounting option for the TOP-N-0.66 transformer on a 35 mm DIN rail.
TShP-N-0.66 current transformers are designed to transmit measurement signals to measuring instruments and are used in electrical energy measurement and metering circuits in 50 Hz AC installations with a rated voltage of 0.66 kV.
Main technical specifications of the TShP-N-0.66 busbar current transformers:
| Characteristic | Value |
| Rated voltage, kV | 0,66 |
| Highest operating voltage, kV | 0,72 |
| Rated secondary current, A | 5 |
| Rated frequency, Hz | 50 |
| Rated primary current, A | 20; 25; 30; 40; 50; 60; 75; 80; 100; 150; 200; 250; 300; 400; 500; 600; 750; 800; 1000; 1200; 1500 |
| Rated secondary burden (cos φ=1), VA | 1; 2,5 |
| Rated secondary burden (cos φ=0.8), VA | 5 |
| Accuracy class | 0,2S; 0,2; 0,5S; 0,5; 1; 3; 5 |
The transformer complies with GOST 7746-2015, GOST IEC 60044-1-2012, and TU BY 300220471.002-2011. The housing components are made of flame-retardant plastic. The warranty period is 5 years. Calibration interval in the Republic of Belarus: no more than 8 years.
The magnetic cores of TShP-N-0.66 support-type instrument current transformers are made of nanocrystalline alloy, electrical steel, or a combination of both.
Overall dimensions of the TShP-N-0.66 transformer.
TShP-N-0.66 transformer mounting option with a screw.
CURRENT TRANSFORMERS TShP-0.66
ALTERNATIVES TO EUROPEAN MANUFACTURERS
Registered in the State Registers of Measuring Instruments of the Republic of Belarus and the Russian Federation; registration in Kazakhstan and Uzbekistan is planned for 2026.
| Busbar current transformers TShP-0.66-60
“width: 25%;”> Busbar
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Busbar
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Busbar
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I1 100-1600 A |
l1 125-2500 A |
l1 200-5000(6000) A |
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| I₂: 5 A; 1 A | |||
| Accuracy class: 0.2S, 0.5S, 0.5, 1.0 | |||
| 1–50 VA | 1–40 VA | 1–50 VA | 1–50 VA |
| Window diameter 52 mm | Window diameter 68 mm | Window diameter 82 mm | Window size 72×122 mm |
| Busbar 120×10×74; 120×8×75; 120×12.5×74; 100×12.5×74; 100×10×74; 100×8×75 | |||
| Maximum operating voltage, kV: 0.72 | |||
| Test breakdown voltage, kV 3.0 | |||
| Overall dimensions W×H×D, mm | |||
| 86,5×110×34 (52) | 108×134×30 (48) | 130×155×45 (63) | 165,3×168,5×42 (60) |
Product Certificates
TPP and TPP-N (1 kV) Instrument Current Transformers
Certificate of the Republic of Belarus on Measuring Instrument Type Approval No. 14071
TOP-N-0.66 and TShP-N-0.66 Instrument Current Transformers
Certificate of the Republic of Belarus on Measuring Instrument Type Approval No. 14396
TShP-0.66m30, TShP-0.66m40 and TShP-0.66m50 instrument current transformers
Certificate of the Republic of Belarus on measuring instrument type approval No. 15679
Republic of Belarus type description for TPP and TPP-N (1 kV), No. 14071
Republic of Belarus type description for TOP-N-0.66 and TShP-N-0.66, No. 14396
Type Description of the Republic of Belarus TShP-0.66m No. 15679
Certificate of Conformity EAEU KG417/045.BY.02.00174
Certificate of Conformity EAEU KG417/045.BY.02.00175
EAEU Certificate of Conformity KG417/045.BY.02.00176
EAEU Certificate of Conformity KG417/055.BY.02.05348
TPP and TPP-N (1 kV) Instrument Current Transformers
Certificate of the Republic of Uzbekistan recognizing the approved measuring instrument type No. 02-2.0647
TShP-0.66m30, TShP-0.66m40 and TShP-0.66m50 instrument current transformers
Certificate of the Republic of Uzbekistan recognizing the approved measuring instrument type No. 02-2.0648
TShP-0.66 instrument current transformers
Certificate of the Republic of Kazakhstan on recognition of measuring instrument type approval No. 2987
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