IEEE 841

[magneticted]

Hi Guys,

Is their a IEE 841 Motor specification for motors above 500 hp and 4160 volts. I'm aware of IEE 841 for 500 hp no ventilated motors upto 4160 volts. The reason for asking is the client is asking for a WPII machine 4kv 575hp according to IEE 841 ? Can you guys advise me. Thanks

 

[Farkel]

IEEE841 only covers low voltage and it is a TEFC servere duty cast iron motor. The spec covers inverter duty, so maybe your medium voltage motor that the customer is after, he wants as inverter duty. WPII is an open motor with screens, so I would peg him down as to his exact requirements and application.

 

[petronila]

Hi Magnetited, You are Right IEEE 841(Mill & Chemical) are high efficiency totally enclosed fan-cooled(TEFC) or non -ventilated up to 4160 Volts and Up to 500 HP. from the 841´s point of view this motor is out of specification, maybe your costumer wants an electrical motor WPII 4 KV 575 HP that meets IEEE841 and this is a special motor.

A short IEEE 841 Standard:

Electrical

designed to meet NEMA MG-1, MG-13 and IEEE 841
90°C rise by resistance method at 1.15 S.F. (or 80°C rise by resistance method at 1.00 S.F.)
motors between 2300V and 4160V use VPI form windings that withstand a surge of 3.5 per unit voltage at a rise time of 0.1 – 0.2ms and 5 per unit voltage at a rise time of 1.2ms or longer
1.15 Service Factor rating
rated for ambient temperature from -25°C to +40°C
3 Leads c/w solderless lug terminals
copper cage rotor construction
NEMA Design B as defined in section 1.17.1.2 of NEMA MG 1-1993
have a nonhygroscopic, chemical and humidity resistant class F insulation system
Mechanical

IP54 rated enclosure
IP55 rated main conduit box with twice the volume specified in NEMA
IP55 rated bearing protection (320T frame and larger)
all ratings are designed for bi-directional rotation
cast iron frame, brackets, hoods and conduit box
frame provided with two (2) threaded drain holes c/w drain plugs and tapped hole on foot for ground lug
foot flatness and shaft runout meet or exceed IEEE 841
automatic corrosion-resistant, replaceable drain plugs
exterior paint consists of one (1) coat zinc chromate epoxy primer and (1) coat of dark blue paint
F-1/F-2 interchangeability
non-sparking plastic or bronze fan
noise level not to exceed 90dB "A"
dynamically balanced rotor designed not to exceed 0.08 inches/second
regreasable bearings with an AFBMA C3 clearance and they are supplied with a rust-inhibiting grease which provides a minimum L-10 life of 30,000 hrs
bearing temperature rise of 50°C for all 2 pole motors and 45°C for all 4 and 6 pole motors.

Regards

PETRONILA

 

[electricpete]

I'm not sure why any customer would have a preference for WPII over TEFC unless there is a limitation associated with frame size for interchangeabilit with existing motor.

Good summary petronilla. What is MG13?

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[rbalex]

You might consider the American Petroleum Institute’s (API) RP541, Form-Wound Squirrel Cage Induction Motors-250 Horsepower and Larger. It has some excellent standard specification forms and instructions on how to use them. Most major NEMA motor manufactures are represented on the API RP541 Technical Committee as well as many users.

There is an overlap in application between the two standards; however there is also an overlap in the Technical Committees. I count at least seven people who are active on both committees.

 

[petronila]

Hi Electricpete,

The MG-13 Belongs to MG1-1998 and is the Standard Frame Assignments for alternating current Integral- Horsepower induction motors.

Regards

Petronila