Power and Distribution Transformers
Oil-immersed, cast-resin dry-type, amorphous-core, pole-mounted and on-load tap changer power transformers from 25 kVA to 63 MVA and up to 145 kV. Designed to the IEC 60076 series, with EU Ecodesign Tier 2 loss levels available, and 100% routine tested before dispatch.
One partner for every step of the network
CASK Power Systems, a division of CASK Electric, designs and supplies transformers and medium-voltage solutions for utilities, industry, infrastructure and renewable-energy projects. Every unit is configured to the project's network, site and efficiency requirements, and each design is optimised for total cost of ownership, not just purchase price.
The transformer range
| Series | Type | Rating | Voltage | Key features |
|---|---|---|---|---|
| CPS-TR001 / TR002 | Hermetic oil-immersed | 25 – 3,150 kVA | up to 36 kV | Sealed, maintenance-free, ONAN / KNAN; TR001 Tier 2 losses, TR002 standard losses |
| CPS-TR005 | Conventional with conservator | up to 10 MVA | up to 36 kV | ONAN / ONAF, Buchholz protection, oil can be treated on site |
| CPS-TR003 | Cast-resin dry-type | 50 – 3,150 kVA | up to 36 kV | AN / AF, class F, E2 C2 F1, no liquid |
| CPS-TR006 | Amorphous-core | 25 – 2,500 kVA | up to 36 kV | Ultra-low no-load losses, class AAA0 |
| CPS-TR004 | Pole-mounted | 25 – 315 kVA | up to 36 kV | Single and three-phase, for overhead lines |
| CPS-TR007 | Power transformers with OLTC | 5 – 63 MVA | up to 145 kV | On-load tap changer, ONAN / ONAF |
| CPS-MV | Compact substations | up to 2,500 kVA | up to 36 kV | MV + transformer + LV in one unit, IEC 62271-202 |
| CPS-TR008 | Special-application | to specification | Earthing, wind, solar, rectifier | |
Hermetic oil-immersed transformers
Totally filled, hermetically sealed design with a corrugated-fin tank. The flexible fins take up the oil's thermal expansion, so there is no conservator and no breather, and the oil never touches the air: minimal maintenance and a long oil life.
- 25 – 3,150 kVA, primary up to 36 kV, secondary 0.4 – 0.69 kV (up to 3.6 kV)
- ONAN with mineral oil or KNAN with natural ester
- Off-circuit tapping ±2 × 2.5 %, vector group Dyn11 (others on request)
- Copper or aluminium windings, CRGO or amorphous core
- Integrated DGPT2 / RIS protection relay and plug-in HV bushings available
Technical data: oil-immersed distribution transformers (CPS-TR001, EU Tier 2)
Maximum losses to EU Ecodesign Tier 2, Um ≤ 24 kV, LV ≤ 3.6 kV, 50 Hz. Standard IEC designs for other markets (CPS-TR002) have higher losses and a lower purchase price.
| Item number | kVA | Uk % | No-load loss, max. W | Load loss at 75 °C, max. W | Efficiency at 100 % load, min. % |
|---|---|---|---|---|---|
| CPS-TR001-001 | 25 | 4.0 | 63 | 600 | 97.42 |
| CPS-TR001-003 | 100 | 4.0 | 130 | 1,250 | 98.64 |
| CPS-TR001-005 | 250 | 4.0 | 270 | 2,350 | 98.96 |
| CPS-TR001-007 | 400 | 4.0 | 387 | 3,250 | 99.10 |
| CPS-TR001-009 | 630 | 4.0 | 540 | 4,600 | 99.19 |
| CPS-TR001-011 | 1,000 | 6.0 | 693 | 7,600 | 99.18 |
| CPS-TR001-013 | 1,600 | 6.0 | 1,080 | 12,000 | 99.19 |
| CPS-TR001-015 | 2,500 | 6.0 | 1,575 | 18,500 | 99.20 |
| CPS-TR001-016 | 3,150 | 6.0 | 1,980 | 23,000 | 99.21 |
Selected ratings. The catalogue lists all 16 ratings from 25 to 3,150 kVA, with sound power levels, dimensions and weights for every model, and a 1,000 kVA reference design (CPS-TR002-011: 11 / 0.416 kV, 1,850 × 1,230 × 1,230 mm, 2,789 kg). Guaranteed values are subject to IEC 60076-1 tolerances.
Transformers with conservator (CPS-TR005)
The proven free-breathing design up to 10 MVA and 36 kV, ONAN / ONAF. A conservator takes up the oil's expansion and a Buchholz relay gives early warning of internal faults. The choice for higher ratings, demanding utility specifications and sites where oil condition must be monitored.
Cast-resin dry-type (CPS-TR003)
50 – 3,150 kVA, up to 36 kV. HV windings vacuum-cast in epoxy resin: no liquid to leak or burn, so the transformer can stand next to the load in buildings, tunnels, data centres and hospitals. Classes E2 · C2 · F1, class F insulation, PT100 sensors, optional fans and IP21 / IP23 / IP31 enclosures.
Power transformers with OLTC (CPS-TR007)
5 – 63 MVA, HV 33 / 66 / 132 kV (Um up to 145 kV), for primary substations, industrial plants and generation step-up. On-load tap changer with AVR panel, conservator with air cell, detachable radiators and fan stages, online-monitoring ready.
Amorphous-core (CPS-TR006)
25 – 2,500 kVA, up to 36 kV, no-load loss class AAA0. The core is wound from amorphous metal ribbon about 0.025 mm thick, with 55 – 75 % lower no-load loss than grain-oriented steel. Example: a 630 kVA unit saves about 2,100 kWh a year against the EU Tier 2 limit. Ideal for solar plants and lightly loaded networks.
Pole-mounted (CPS-TR004)
25 – 315 kVA three-phase and 10 – 167 kVA single-phase, up to 36 kV, for overhead rural and suburban lines. Hermetically sealed, with pole-mounting brackets, arcing horns or surge arresters and a weather-resistant paint system.
Compact substations (CPS-MV)
MV switchgear, a transformer up to 2,500 kVA and the LV board in one factory-built enclosure to IEC 62271-202, delivered ready to connect. Series CPS-MV9000, MV9500, MV10000 and MV10500. See also our MV switchgear and transformer kiosks.
Special-application (CPS-TR008)
Earthing transformers, solar PV and wind turbine step-up units, rectifier and converter transformers, auxiliary transformers and IEEE pad-mounted units, designed to the duty cycle, harmonics and site conditions.
Mineral oil or natural ester
Mineral oil to IEC 60296, or natural ester to IEC 62770 with a fire point above 300 °C (fire class K) and ready biodegradability, so transformers can stand closer to buildings and sensitive sites.
Accessories and protection
Plug-in or porcelain bushings, cable boxes, DGPT2 / RIS relays, Buchholz relays, temperature indicators, PT100 sensors and digital relays, surge arresters, marshalling boxes and anti-vibration pads.
Tested before it leaves
Every transformer gets the full routine test programme of IEC 60076-1 and is delivered with its test report. Type and special tests are done on request or as the contract requires, in-house or at accredited independent laboratories, and witness testing can be arranged.
- Routine tests: winding resistance, voltage ratio and phase displacement, impedance and load loss, no-load loss and current, applied and induced voltage, leak test, insulation resistance
- Type tests: temperature rise, lightning impulse, sound level
- Special tests: dynamic short circuit, SFRA, dissolved gas analysis, tan δ and more
What we need for a quotation
The catalogue ends with an enquiry data sheet you can fill in and send to [email protected].
Frequently asked questions
Which standards do your transformers meet?
They are designed and tested to the IEC 60076 series (IEC 60076-11 for dry-type), with EU Ecodesign Regulation 548/2014 as amended by 2019/1783 (Tier 2) available, and IEEE C57.12 on request. The catalogue lists all applicable standards.
Hermetic or conservator: which should I choose?
Hermetic transformers need minimal maintenance, have no oil–air contact and a lower height, and are typical from 25 to 3,150 kVA. Conservator transformers allow oil monitoring and treatment on site and are preferred for higher ratings and demanding utility specifications.
Can you meet EU Ecodesign Tier 2 losses?
Yes. The CPS-TR001 hermetic and CPS-TR003 cast-resin series are offered at Tier 2 loss levels, and amorphous-core units reach class AAA0. For markets outside the EU, losses are designed to the national standard or your specification.
Are dimensions and weights guaranteed?
Catalogue dimensions and weights are indicative. Certified dimension drawings and guaranteed data are sent with every offer and approval drawing.
Related products
Need a transformer for your project?
Send us the rating, voltages and site conditions. We will propose a design with guaranteed losses, impedance and dimensions.
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Address: Barbaros Mah., Nida Kule, No: 2
Ataşehir, Istanbul, Türkiye
Phone: +90 216 410 22 44
Email: [email protected]
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