YWKK / YWKS Non-Sparking HV Motor, Ex nA, 6/10 kV

The YWKK (air-to-air cooled) and YWKS (air-to-water cooled) are high-voltage non-sparking ("n") three-phase induction motors from Nanyang Explosion Protection Group for shaft heights 355 to 630 mm, at 6 kV and 10 kV. They are an optimised series based on Nanyang's long production of non-sparking high-voltage motors, and the economical choice for Zone 2 gas areas.

The motors comply with GB 755, JB/T 7593 and IEC 60034, and their explosion protection with GB 3836.1-2010 and GB 3836.8-2014 (type "n").

Key Specifications

Where Non-Sparking Motors Fit

A non-sparking motor produces no arcs, sparks or hot surfaces in normal operation, so it is permitted in Zone 2, where an explosive gas atmosphere is not expected in normal operation and exists only briefly. It is lighter and lower in cost than a flameproof motor and needs no purge system. In the current IEC 60079-7 the same protection for motors is marked Ex ec; tell us which marking your specification uses. For Zone 1 choose the flameproof YBXKK or the pressurized YZYKK.

Construction

• Box-type frame in bent steel plate with cast-iron end shields; remove the cooler to inspect the inside
• Stator pressed in from outside; flat copper coils with double glass-film tape, class F, whole-stator VPI
• Standard: 6 stator PT100 (one working, one spare per phase), 2 bearing PT100, anti-condensation heater 220 V AC, 400 W
• Main terminal box IP55 on the right; neutral point brought out above 2000 kW; current transformers on request
• Cable entry: flared inlet (cable Ø38 - 62 mm) as standard; threaded conduit G2½ or M75×1.5 glands optional
• Water-leakage monitor terminal box on YWKS
• Rotation clockwise or counter-clockwise; 6-pole and above bidirectional; metal centrifugal fans

Bearings

Sleeve bearings use L-TSA32 oil (2-pole) or L-TSA46 (4-pole and above), external supply at 0.01 - 0.03 MPa. Rolling bearings have on-line grease inlet and drain.

Air-to-Water Cooler (YWKS)

Inlet water pressure 0.35 - 0.45 MPa, inlet temperature up to 33 °C.

Purging

As standard the motor has manual purge inlet and outlet ports; an automatic increased-safety purge unit can be supplied on request.

Performance Data

Guaranteed values from the catalog for every standard rating. Click a table to open it; send us the rating you need and we confirm the current data sheet.

Ordering Example

YWKK500-2, 10 kV, 710 kW, 50 Hz, 2 poles, Ex nA IIC T3 Gc, IM B3, IC611, IP55, clockwise, outdoor (W), ≤ 1000 m.

Model Code

Example YWKK630-4W: Y = induction motor, W = non-sparking, KK = air-to-air (KS = air-to-water) cooling, 630 = shaft height (mm), 4 = poles, W = outdoor.

Common Questions

Can YWKK be used in Zone 1?

No. Non-sparking motors are for Zone 2. Use YBXKK (flameproof) or YZYKK (pressurized) in Zone 1.

Is a purge system required?

No purge system is required for type "n"; manual purge ports are fitted, and an automatic purge unit is optional.

What is the difference between YWKK and YWKS?

YWKK is air-to-air cooled (IC611); YWKS is air-to-water cooled (IC81W) with a water-leakage monitor.

Documents Supplied with the Motor

For each order we can provide the technical data sheet, outline drawing, routine test report and, for explosion-proof motors, a copy of the Ex certificate that matches the nameplate marking. Tell us in the inquiry which documents your project or your inspector requires, so they are prepared before shipment.

Related Products

• YZYKK / YZYKS: pressurized Ex p motor for Zone 1
• YXKK / YXKS: non-explosion-proof box-type motor

How to Order

For a fast, accurate quotation please send: rated power (kW), voltage and frequency, number of poles or speed, Ex marking or hazardous zone, mounting type, quantity and destination port. For a replacement, a photo of the old motor nameplate is the quickest way to match it.