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YKK / YXKK

YKK and YXKK Series High-Voltage Three-Phase Induction Motors

Cage-rotor high-voltage machines in frames 355 to 630, at 6 kV or 10 kV, covering the mill, blower, compressor and hoist duty that dominates heavy industry.

6 kV / 10 kV185–3150 kWIC611 / IC616
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YKK / YXKK high-voltage three-phase induction motor

YKK and YXKK are high-voltage squirrel-cage three-phase induction motors. The two designations mark the efficiency step: YKK meets grade 3 of GB 30254—2013 and YXKK grade 2, as assigned by the product standards these machines are built to. The 6 kV range is built to JB/T 12730-2016 and the 10 kV range to JB/T 12729-2016.

Construction and mounting is IMB3, rating is continuous duty S1, and cooling is air-to-air or air-to-water heat exchange (IC611 / IC616) rather than the open frame ventilation used on older high-voltage designs.

Power, metallurgy, building materials and petrochemicals together account for the bulk of the domestic high-voltage motor market, followed by oil and gas, steel, coal, cement and paper — which is a fair description of where these machines end up.

Note on efficiency classes: the IE scale of IEC 60034-30-1 applies below 1000 V, so it has never covered these machines. Since February 2024 there is a separate high-voltage scale — IEC 60034-30-3 defines IE1 to IE4 for fixed-speed high-voltage cage induction motors between 200 kW and 2000 kW. Part of this range sits inside that window and part of it does not. We have not yet classified the series against it, so the figure we quote is the GB grade assigned by the product standards, not an IE number. If your specification calls for an IE class at high voltage, raise it early and we will tell you where the specific rating stands.

Core specifications

ParameterValue
Frame size6 kV: H355 – H630 mm · 10 kV: H400 – H630 mm
Power range6 kV: 185 – 3150 kW · 10 kV: 220 – 2500 kW
Voltage & frequency6000 V or 10000 V, 50 Hz
EfficiencyGB 30254—2013 — YKK grade 3, YXKK grade 2 (the edition referenced by the product standards; see note below)
Protection degreeIP54 / IP55
CoolingIC611 / IC616
Insulation classClass F
MountingIMB3
Duty typeS1 (continuous)
Ambient / altitude40 °C · up to 1000 m

Standards and certification

  • JB/T 12730-2016 (6 kV series)
  • JB/T 12729-2016 (10 kV series)
  • GB 30254—2013 (high-voltage motor efficiency) — the edition normatively referenced by JB/T 12730—2016 and JB/T 12729—2016, which is where the grade 3 / grade 2 assignment comes from. GB 30254—2024 superseded the 2013 edition on 1 September 2025; re-assessment of these ratings against the new edition is in progress and we will state the result rather than assume it carries across.

Typical applications

  • Power generation — cooling fans, pumps and auxiliary plant
  • Metallurgy — blast furnace blowers, rolling mills, coilers
  • Petrochemicals — compressors, pumps, agitators
  • Mining — hoists, conveyors, crushers
  • Building materials — cement mills, crushers, conveyors
  • Water treatment and environmental plant — pumps and fans

Selection guide

Same machine platform, different efficiency grade — YXKK is the higher one. At these ratings the efficiency difference is a large absolute number, so on continuous duty YXKK usually wins the total cost comparison comfortably.
It follows the site distribution, not the motor. Where both are available, 10 kV lowers the current and the cable cost for the same power; 6 kV switchgear is more common in older plants.
Model, rated power, rated voltage (6000 V or 10000 V), rated frequency, synchronous speed, mounting (IMB3), protection degree (IP54/IP55), cooling method (IC611), insulation class (F) and site conditions. Ambient above 40 °C or altitude above 1000 m both change the design.

FAQ

Datasheets, dimension drawings and certification copies are issued on request — tell us the rating and we will send the documents for that specific model.

Downloads

DatasheetPDF · 2.3 MBDownload
Installation & maintenance manualInstallation, commissioning and servicingRequest
CertificationCertificates and test reportsRequest

Certificates and test reports are issued against the specific model and rating rather than the series, so we send the ones that apply to your order. Tell us the rating and the market and we will send them.

Related products

YE3 Compact HV

Compact 3.3 kV / 6 kV, 185–3150 kW

YE3 Large-Power

IE3, 200–1000 kW low voltage

TYP Series

Variable-frequency PM synchronous

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Request a quote — YKK / YXKK

Tell us the rating, quantity and application and an engineer will come back with a specification, the documents for that model, and a price.

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