Table of Contents

1 General
2 Work to Be Done by Others
3 Drawings and Data
4 Performance
5 External Motor Control
6 Electric Motor
7 Control Panel


1 General

1.1 Description

This specification covers the minimum requirements for a three phase stepless speed controlled squirrel cage induction motor, including all auxiliary and control equipment installed in a speed control panel for a speed control of the motor.

1.2 Codes and Regulations

Motor and control panel shall be designed and fabricated in accordance with this specification, the relevant requisition, noise data sheets and the current edition including amendments of the following rules and regulations:

- All applicable local rules and regulations of the country of equipment installation as stated in the requisition

- Requirements of power supplier

- EEMUA Publication no. 132 for three-phase cage induction motors

- Referenced documents as stated in the requisition.

1.3 Certificate

Motor shall be installed in a classified area.

Manufacturer of equipment shall supply a test certificate from a recognized laboratory stating that the motor is constructed and approved to work in a classified area as stated in the requisition over the whole specified speed range and under all specified continuous operating conditions.

If the motor is equipped with a separate cooling unit the required test certificate of motor shall include the cooling unit.

1.4 Site Conditions

Motor shall be installed outdoors and shall withstand a very corrosive chemical and refinery environment without any additional protection supplied by purchaser.

The motor shall be suitable for operating continuously over the whole speed range and under all continuous operating conditions at a maximum ambient temperature of 40ºC.

If additional motor cooling is required, the manufacturer of the equipment shall supply and install the necessary equipment for this additional cooling with respect to the specified area classification.

The control panel shall be totally metal-enclosed and shall be installed indoors in a safe area and shall be suitable for operation with maximum equipment heat losses at a maximum panel ambient temperature of 40ºC.

If additional panel cooling will be required, the manufacturer of the equipment shall supply and install all necessary equipment for this additional cooling.

1.5 Conflicting Requirements

In case of conflicts between the documents and conditions mentioned above or between these and the specification in hand the severest requirements will govern.It will be the manufacturer’s responsibility to design, fabricate and test the motor and speed control panel in a completely functional manner.

A deviation from this specification will only be acceptable in case vendor has specified in his quotation the requirements he cannot meet and Company has accepted this deviation in writing before award of order.

Noncompliance will be interpreted by purchaser as confirmation that manufacturer will meet this specification and any subsequent extra cost shall be for equipment manufacturer’s account.

1.6 Coordination

The manufacturer of the equipment shall furnish all the technical information needed by the manufacturer of driven equipment and Badger within six weeks after having received the torque speed curve, required power, speed range and moment of inertia of driven equipment.

2. Work to Be Done by Others

- All civil work at site.

- Installation of speed control panel at site.

- Installation of motor on driven equipment base plate or on a concrete foundation.

- Cabling to speed control panel, main motor, motor for extra cooling main motor (if required), local driven equipment panel, control room panel, etc. shall be supplied, installed and connected by others.

- Coupling between motors and drivenequipment shall be supplied by vendor of driven equipment.

This vendor shall be instructed to send motor coupling half to motor manufacturer for machining and mounting.

3. Drawings and Data

Drawings and other technical data shall be furnished in the quantities specified in the requisition.

3.1 Drawings and Data to Be Furnished with Quotation

- Key diagram with main components.

- Control diagram.

- Preliminary outline dimensions and approximate weights of motor and speed control panel.

- Front view drawing showing meters, switches, signal lights, etc.

- Cooling system of motor and panel.

- All technical information such as: efficiency of combined system motor/panel under several load conditions, power factor, estimated value of higher harmonic components in the range between 150-750 cycles of a standard model network, protection of electronic equipment for short circuit currents and abnormal temperature rise etc.

- Estimated noise levels with frequencies produced by motor and panel.

- Certificate for explosion protection of a similar motor for the same area classification as stated in the requisition.

- Reference list with outputs, speed ranges and dates of delivery of the equipment.

3.2 Drawings and Data to Be Submitted for Approval after Order Award.

- Key diagram with all documents.

- Control diagram(s) in detail.

- Final outline dimensions, weights and exact location of terminal boxes and other auxiliary equipment of motor and panel.

- Cable connection diagrams of all equipment with identification of all terminals and terminal blocks.

- Eight weeks before delivery date indicated in the order manufacturer shall supply installation, start-up, operating and maintenance instructions.

- After inspection at factory, manufacturer shall supply test and inspection reports including values of higher harmonics in the specified frequency ranges.

- Test certificate that motor and motor cooling system is suitable for installation in a classified area as stated in the requisition.

4. Performance

4.1 Motor and control equipment shall be suitable to drive the driven equipment continuously under all specified conditions at any frequency between minus 5% and plus 2% of the nominal frequency together with any voltage between minus 5% and plus 5% of the nominal network voltage.

4.2 The nominal network voltage will be 380/220 volts, 50 cycles with the neutral solidly grounded.

4.3 Motor and control equipment shall be suitable to accelerate the driven equipment with an equipment voltage of 80% of the nominal voltage during the reacceleration time after a short power failure for automatic restart of the plant.To ensure an adequate acceleration torque the minimum margin between motor torque and required driven equipment torque shall be under the 80% of the nominal voltage conditions not less than 10% of the required torque.

4.4 The motor connected to the driven equipment shall be suitable for at least 3 starts per hour from zero to full speed in quick succession starting the motor from cold condition and two starts per hour in quick succession under the same conditions after a continuous run of the motor. During above mentioned starts no part of a explosion-protected motor may reach a temperature above the temperature classification stated in the requisition.

4.6 Motor, coupling and control equipment shall be suitable for reswitching into the network after a short power failure with motor full residual voltage opposing the supply voltage.

5. External Motor Control

A start-stop switch and a hand-automatic switch shall be installed near the motor.

After the start signal has been given, the motor shall accelerate to the minimum speed in the specified speed range. In the position “ automatic “ of the H-A switch the speed of the motor shall be automatically controlled by a process signal within the specified speed range.

In the position hand of the H-A switch the speed of the motor shall be controlled by hand either locally at the motor or in the main control room.

The panel shall be provided with terminals for externals electrical interlocking, close contact when interlock is made, and trip contact close on failure, and one open and one close contact for external on-off signalling.

6. Electric Motor

6.1 Windings

Motor windings shall be provided with 6 temperature detectors for winding protection two per phase, one for alarm, and one for trip.

The temperature detectors shall be wired to a separate terminal box and this box shall be labeled “ stator temperature detectors “.

Class “ F “ winding insulation shall be applied and shall be limited to class “ B “ temperature rise.

Stator windings shall be fully insulated for an unearthed electrical system. Special attention shall be paid to the introduction of higher heat losses for the nonsense supply wave form.

6.2 Terminal Boxes

Location of main terminal box shall be as specified in the motor data sheet.

Cast iron terminal boxes will be acceptable for motors protected by fuses.

The main terminal box shall be rotatable on its mounting face by steps of 90ºC.

6.3 Earthing

The motor frame and the inside of the main terminal box shall be provided with an earthing terminal of the same size as the main terminal.

6.4 Bearings and Bearing Lubrication

Grease - lubricated ball and roller bearings will be preferred with maximum ball and roller speed as indicated by the manufacturer of bearings considering the maximum speed of the motor in the specified speed range.

The calculated life time of bearings with a maximum ambient temperature of 40ºC and under the estimated bearing loads shall be at least 40,000 working hours for motors with regreasing devices and for motors with lubrication for a life of at least 26,000 working hours.

Motors above 11 kW shall be provided with devices for regreasing of bearings, and these devices shall be constructed so that the motor does not need to be stopped during regreasing.

The time interval between two regreasing operations shall be at least 4000 hours under above mentioned conditions.

Motors with regreasing devices shall have a separate tag plate with indication of type and quantity of grease required.

The manufacturer of the motor shall make all the necessary arrangements to prevent bearing damage during transport of motor.

6.5 Vibration

Rotor and fan shall be balanced to ensure a smooth run of the motor within the specified speed range and under all load conditions of the motor.

Half coupling may not be used for balancing of rotor.

Removal and mounting of the fan may not disturb the smooth run of the motor.

Special attention shall be paid to prevent the critical speed of the motor from lying within the speed range of motor. The speed range of the motor is the specified speed range stated in the requisition plus 10% overspeed over the maximum speed.

For limits of vibration the German VDI 2056 shall be observed.

For electric motors up to and including 15 kW the maximum acceptable vibration shall be if motor is running in the group “ K “ with selection range “ good “ and for electric motors up to 160 kW the maximum acceptable vibration shall be if motor is running in the group “ M “ with selection range “good “.

6.6 Cooling of Motor

Motor shall be forced air-cooled.Cooling of the motor by its own shaft-driven fan is preferred within the speed range and output given in the requisition. If this cooling system is not sufficient, the motor shall be provided with a cooling system which is independent of the speed of the motor. This cooling system and the motor shall be assembled as one unit.

The direction of air flow from the fan shall be towards the driving end of the motor. The fan shall be made of nonsparking material.

7. Control Panel

Panel shall be made of sheet steel and shall be of the free-standing type without back access. Replacement of components installed in the panel shall be possible from the front side only. Degree of protection in accordance with IEC 529 shall be IP 54.

The outside and inside of the enclosure shall be painted with three layers of paint. The three layers shall form a paint system which is resistant to the mentioned site conditions.

Panel shall have a storage facility for service documentation. Bottom of panel shall be provided with a bolted undrilled gland plate.