FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION
A system for testing multiple induction motors
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai - 400 030, Maharashtra, India, an Indian Company
INVENTORS
Naresh Narra and Umamahesh Pasumarthi of Crompton Greaves Limited , Eelectronics Design Centre, Global R&D Centre, Kanjurmarg (E), Mumbai 400042, Maharashtra, India, both Indian Nationals.
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the nature of this invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
This invention relates to an automated system for testing multiple induction motors.
BACKGROUND OF THE INVENTION
The factory testing of induction motors includes monitoring of several electrical and thermal parameters and checking for acceptable performance levels. Testing and monitoring of multiple induction motors under operation involves a manual inspection and obtaining reading for each of the induction motor. Performance of the motors can be assessed by comparing the measured parameters with standard specifications for which the motor is designed. For e.g. circle diagrams are drawn for the measured parameters and compared against a known standard. Such a manner of testing and monitoring becomes laborious and prone to manual errors. There is a need for an automated system in which multiple induction motors are monitored for their electrical and thermal parameters from a central location.
OBJECTS OF THE INVENTION
An object of the invention is to provide an automated system to test and monitor various electrical and thermal parameters of induction motors.
Several aspects of the invention are described below with reference to examples for illustration. It should be understood that numerous specific details, relationships, and methods are set forth to provide a full understanding of the invention. One skilled in the relevant art, however, will readily recognize that the invention can be practiced without one or more of the specific details, or with other methods, etc. In other instances, well known structures or operations are not shown in detail to avoid obscuring the features of the invention.

DETAILED DESCRIPTION OF THE INVENTION
According to the invention a system for testing induction motors is provided. The system comprises of
a plurality of test beds each one of the test beds housing an induction motor and a sense means to receive electrical signals corresponding to electrical and thermal parameters to be tested; and a plurality of signal processing units corresponding to each of the plurality of test beds receiving the electrical signals and processing them to generate characteristic information for the corresponding induction motor; and a central processing means to receive the characteristic information from each of the signal processing units, compare the characteristic information with standard specification for the induction motors are manufactured, perform analysis on the characteristic information and maintain a database for the received and analyzed information.
The following is a detailed description of the invention with reference to the accompanying drawing, in which:
Figure 1 is a schematic representation of a single test bed connected to a signal processing system according to an embodiment of the invention.
Figure 2 is a schematic representation of multiple test beds and corresponding signal processing systems connected to a host machine according to an embodiment of the invention.
Figure 1 is shown comprising of a test bed 110 connected to a signal processing unit 120. Test

bed 110 facilitates the testing of a motor 112 attached to a load 111. Temperature sensor units
113 are electrically coupled to the induction motor 112 and capture the temperature of various
component in a induction motor for e.g. stater windings , rotor windings, bearing, slip ring etc .
In a factory shop floor scenario several of such test beds can be employed to gather electrical and
thermal parameters for the induction motor. The power consumption of the motor 112 is
monitored by current transformer 114 and voltage transformer 115. Signal processing unit 120 is
connected to test bed 110 to receive electrical signals from temperature sensor unit 113, current
transformer 114 and voltage transformer 115. Temperature sensor unit 113 receives temperature
data from various temperature sensors placed in the induction motor 112. Signal processing unit
120 is shown containing a data acquisition module 121, an A/D converter 122 and a
microcontroller unit 123. A/D converter 122 digitizes the analog electrical signals it receives
from current transformer 114 and voltage transformer 115. Data, acquisition module 121 receives
temperature data from temperature sensor unit 113. Microcontroller unit 123 can be programmed
to calculate electrical and thermal parameters like active power, reactive power factor bearing
temperature, winding temperature slip-ring temperature etc in the motor 112. Microcontroller
unit 123 can be connected to a LAN network using a network interface card as commonly used.
Figure 2 is shown comprising of multiple test beds electrically coupled to signal processing units connected to a host computer 210. 201, 202, 203 represent test bed and signal processing unit coupled together. 201-203 transfer electrical and thermal parameter data to a host computer 210. The data transferred by each of 201-203 can be stored in host computer can be used to perform analysis of each data. Host computer 210 additionally stores standard specification data for which each induction motor is designed for. The standard specification data can be compared to

the test data (electrical and thermal parameters) as received for each induction motor. Host computer 210 may additionally program signal processing units of 201-203 to operate for certain time-intervals to selectively receive electrical information for the induction motors. Host computer 210 may additionally calculate circle diagram and graphical representation for each of the induction motors under test.

We Claim
1. A system for testing induction motors, comprising:
a plurality of test beds each one of the test beds housing an induction motor and a sense means
to receive electrical signals corresponding to electrical and thermal parameters to be tested; and
a plurality of signal processing units corresponding to each of the plurality of test beds receiving
the electrical signals and processing them to generate characteristic information for the
corresponding induction motor; and
a central processing means to receive the characteristic information from each of the signal
processing units, compare the characteristic information with standard specification for the
induction motors are manufactured, perform analysis on the characteristic information and
maintain a database for the received and analyzed information.
2. The system for testing induction motors of claim 1, the central processing means receives
the electrical signals from the plurality of signal processing units according to TCP/IP protocol.