FORM2
THE PATENTS ACT, 1 970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the invention: AN IMPROVE]) AUTOMATED SYSTEM AND
A METHOD FOR TESTING MCCB'S FOR INTERNAL ACCESSORIES BY INTERFACE METHOD
2. Applicant(s):
(a) NAME : LARSEN & TOUBRO LIMITED
(b) NATIONALITY : An Indian Company
(c) ADDRESS: L & T House. Baiiard Estate, Mumbai 400 001,
State of Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed;

Field of the invention
The present invention relates to an improved automated system and a method for testing a moulded case circuit breaker for internal accessories by interface method. More particularly, the invention is concerned about measuring and comparing operational parameters of a moulded case circuit breaker against a specified band of values of operational parameter. This band has been set by after cross checking the breakers with actual accessories for their working. The values were finalized through a statistical study.
Background and the prior art
In an electrical system the internal accessories of MCCBs play the role of relaying the status of the breaker i.e. ON/OFF/TRIP state or to trip the breaker under certain conditions.
Thus these breakers are required to be tested during assembly stage of the circuit breaker. A dummy accessory can be used to test the breaker. A dummy accessory will deteriorate in its functioning after repeated use which may cause even a Not OK breaker to pass.
US 7,788,055 describes a method and system to calibrate a motor circuit protection device is disclosed. An example method calibrates a signal chain of a circuit breaker. The signal chain includes a current transformer, a burden resistor, a stored energy circuit and a controller. The circuit breaker includes a memory coupled to the controller. A calibration instruction routine is written in a first location of the memory. A test current is injected in the circuit

breaker signal chain. The test current peak of the test current in the circuit breaker signal chain is measured. Data indicative of the test current peak is stored in a second location of the memory. The test current peak data is read from the second location of the memory. The test current peak data is compared with nominal current data related to the signal chain remotely from the circuit breaker. A calibration factor is determined based on the comparison. The prior art doesn't take into account the mechanical parameters of the circuit breaker responsible for the actuation of accessories that provide the necessary signals for control and indication to the control panel depending upon the state of the breaker.
CN 101592559 (A) teaches that a system for testing mechanical properties of an integral circuit breaker, which comprises a host computer and an interface board is arranged on the host computer, wherein the interface board is provided with a testing line, an AC-DC terminal, a speed testing terminal, a vibration testing terminal, a direct current voltage testing terminal, an alternating current voltage testing terminal, an A-phase fracture, a B-phase fracture, a C-phase fracture and a common port terminal, wherein the interface board is connected with a sensor through the testing line. The sensor is provided with a bracket and a magnetic base. The system has abundant program control functions, wherein the sensor includes the triggering mode, the channel selection, the triggering level, and a sampling time base, a recording parameter block and the like which can be set through program control, and also includes incomparable abundant triggering functions. The system provides an ideal and effective testing tool for carrying out the overhaul of the state of a high-voltage circuit breaker for an electric power system, can be used for testing the mechanical properties of the circuit breaker on line, and performs data storage, analysis and comparison

so as to quickly and accurately diagnose the health condition of the circuit breaker on line. The prior art does not teach the use of a variety of sensors integrated to provide simulation of the functioning of accessories through the measurement of critical parameters at breaker positions that are responsible for the functioning of accessories in the breaker during breaker simulation.
CN 101509955 (A) discloses an automatic testing system of characteristic parameters of a direct-current breaker, which consists essentially of an analyzing and managing system controlled by a computer, a digital storage oscillograph and a program-controllable direct-current power source. 12-bit digital values that are output by a single chip microcomputer output 0 to 5V voltage through a digital-to-analog converting circuit, and the voltage is output to a phase-shifting-control full-bridge zero-voltage switching and a pulse modulation converting circuit through an isolating amplifier as well as to an EA+ end of a main chip, thus changing output current. The electromagnetic tripping action time is measured by a waveform breaking method and taking the largest constant short-circuit current in electromagnetic instantaneous acting tripping as the starting point of timing, thus having the advantages of high accuracy, efficiency and reliability. It was not known from the prior art that testing of the breaker can be done without passing any rated current across the terminals of the breaker. Further program controllable direct-current power source to measure the electromagnetic trip action time was not taught in the prior art.
Therefore, there is a need to provide an improved automated system and a method for testing internal accessories of a moulded case circuit breaker by interface method. The present invention thus ensures that the breaker parameter readings are always compared against the set band. Breaker referencing is first ensured before interface testing. Thus after it is properly

referenced in all the three directions, the breaker is operated by a mechanism. During these operations, the parameters of the breaker responsible for the working of the accessories are measured and compared against the specified band. The band is specified after calculating the factor from the master breaker and using statistical methods after testing numerous breakers
Objects of the invention
One object of the present invention is to overcome the drawbacks/disadvantages of the prior art.
The basic object of the present invention is to provide an improved automated system for testing the functioning of internal accessories of a moulded case circuit breaker by interface method.
Another object of the present invention is to provide a method for testing internal accessories of a moulded case circuit breaker by interface method.
Summary of the invention
According to one aspect of the present invention there is provided an
improved automated system for testing the parameters of a moulded case
circuit breaker responsible for the functioning of internal accessories, said
system comprising :
loading station means for loading circuit breaker to be tested in a test cavity
at test station such that the circuit breaker is always positioned at the same
position;

measurement modules for measuring initial parameters of the circuit breaker;
means for determining position of resetter assembly during TRIP to RESET
operation;
plurality of probe means for determining position of driveshaft between ON
and OFF position of the circuit breaker;
means for determining trip force of the circuit breaker during ON to TRIP
operations;
controller means for comparing the said parameter readings with a
predetermined band so as to predict the parameters which are closer to
critical values of the band,
According to another aspect of the present invention there is provided a
method for testing the parameters of a moulded case circuit breaker
responsible for the functioning of internal accessories, said method steps
comprising ;
loading circuit breaker to be tested in a test cavity at test station such that the
circuit breaker is always positioned at the sameposition;
measuring initial parameters of the circuit breaker;
determining position of resetter assembly during TRIP to RESET operation;
determining position of driveshaft between ON and OFF position of the circuit
breaker;
determining trip force of the circuit breaker during ON to TRIP operations;
comparing the said parameter readings with a predetermined band so as to
predict the parameters which are closer to critical values of the band.
Brief description of the accompanying drawings
Fig 1 illustrates diagrammatic representation of the breaker showing the cavity where accessories are fitted and also the breaker mounting hole.

Fig 2 illustrates diagrammatic representation of different states of a circuit breaker.
Fig 3 illustrates diagrammatic representation of the movement of breakers in the top view of the setup.
Fig 4 illustrates diagrammatic representation of the side view of the setup depicting the test station cavity.
Fig 5 illustrates diagrammatic representation of the test cavity depicting the various measurement modules.
Fig 6 illustrates diagrammatic representation of the probe for measuring Driveshaft position in the circuit breaker.
Fig 7 illustrates diagrammatic representation of the probe for measuring TAC actuator position in various states in the circuit breaker.
Fig 8 illustrates diagrammatic representation of the bracket for simulating ROM condition in the circuit breaker to make the breaker ON-OFF state.
Detailed description of the accompanying drawings
According to the invention, there is provided an improved automated system and a method for testing the functioning of internal accessories of MCCB's by Interface method. As shown in figures 1 and 2, the breaker showing the cavity where accessories are fitted and also the breaker mounting hole and different states of a circuit breaker respectively. The breaker is loaded on the

automated system in TRIP state. A part presence sensor senses the presence of the breaker and transfers the breaker to the loading station (1).
Use of internal accessories of IWCCB's in an electrical system and the parameter used for testing the breaker
The shunt release is used for remote tripping of the breaker and the driveshaft of the breaker actuates the lever of the shunt release. The system checks the position of the driveshaft of the breaker in ON state.
Undervoltage release is used to trip the breaker whenever the line voltage reduces to a specified limit. The UV resetter assembly of the breaker actuates this release in RESET state of the breaker. The system measures the position of UV resetter assembly in RESET state.
Trip Alarm contact (TAC) accessory is used to determine the TRIP state of the breaker. The TAC actuator actuates this accessory. The system checks the position of the TAC actuator in TRIP and ON state. The system uses a probe (9) for measuring TAC actuator position in various states in the circuit breaker as shown in figure 7.
Auxiliary accessory is used to determine the ON/OFF state of the breaker. The driveshaft of the breaker actuates this accessory. The system checks the position of the driveshaft of the breaker in ON state.
Rotary Operating mechanism is responsible to make the breaker ON and OFF. Hence it is dependent on the travel of the knob of the breaker.

Test station
The breaker is referenced using the breaker mounting hole axis which ensures that the breaker always come and rest at the same position. Hence the present invention ensures that the breaker movement is restricted in X-Y axis as shown in figure 3. When the breakers are loaded inside the test cavity (2) the breaker surface rests on four butting pins (7) thus ensuring that the breakers movement is restricted in Z axis as shown in figure 4.
The measurement devices and their interfacing modules grab the initial reading of the parameters. As shown in figure 5, the various measurement modules comprise a continuity module (3), a trip force measurement module (5), a driveshaft module (4) and a TAC actuator measurement module (6) for measuring the readings of the parameters. Then the breaker is operated from TRIP state io RESET state. During this time the position of the UV resetter assembly is measured,
The breaker is made ON and then OFF. During this time the ON and OFF position of the breaker are recorded. Also the driveshaft position in both cavities is measured. The system for testing and measuring parameters of internal accessories of a moulded case circuit breaker uses plurality of probe means (8) for determining position of driveshaft in the circuit breaker as shown in figure 6.
The breaker is made ON by moving it from TRIP to RESET and then to ON state to trip the breaker on RHS side. During this time the trip force of the breaker is measured on RHS side.

Again the breaker is made ON by moving it from TRIP to RESET and then to ON stateto trip the breaker on LHS side. During this time the trip force of the breaker is measured on LHS side
The controller then compares the reading against the specified band. This band is specified after calculating the factor from the master breaker and using statistical methods after testing numerous breakers.
Actual reading displayed = Actual reading captured by the automated setup + Factor derived from master breaker when put inside the setup.
The System for testing and measuring parameters of internal accessories of a moulded case circuit breaker further comprises a substantially C shaped bracket means (10) adapted for simulating ROM condition in the circuit breaker to make the breaker ON-OFF state and a ball screw arrangement. The ball screw arrangement (11) is operated by a motor means. A ball screw arrangement (11) is operatively attached to the C shaped bracket means (10) as shown in figure 8.
Thus this method and system gives the actual reading of the critical parameters of the breaker. Using this method and system, the present invention is able to predict whether the breaker has any parameter closer to the crticai (unfavorable) side. This is not possible incase of testing with dummy accessories.
Advantages
1. The time taken for testing a breaker using the interface method is far less than the time taken to manually check all the accessories one by one.

2. Leads to productivity improvement.
3. Dummy accessory is not required.lt also leads to monetary saving of accessories.
4. Reduction in manpower as it is an automated system.
The invention has been described in a preferred form only and many variations may be made in the invention which will still be comprised within its spirit. The invention is not limited to the details cited above. The structure thus conceived is susceptible of numerous modifications and variations, all the details may furthermore be replaced with elements having technical equivalence. In practice the materials and dimensions may be any according to the requirements, which will still be comprised within its true spirit.
Loading station 1
Test station cavity 2
Continuity module 3
Driveshaft module 4
Trip force measurement moduie 5
TAC actuator measurement module 6
Reference butting point 7
Probes for measuring drive shaft module 8
Probes for measuring TAC actuator position 9
C shaped bracket 10
Ball screw arrangement 11

WE CLAIM
1. A method for testing parameters of a moulded case circuit breaker
responsible for the functioning of internal accessories, said method
steps comprising :
loading circuit breaker to be tested in a test cavity at test station such
that the circuit breaker is always positioned at the same position;
measuring initial parameters of the circuit breaker;
determining position of resetter assembly during TRIP to RESET
operation;
determining position of driveshaft between ON and OFF position of the
circuit breaker;
determining trip force of the circuit breaker during ON to TRIP
operations;
comparing the said parameter readings with a predetermined band so
as to predict the parameters which are closer to critical values of the
band.
2. Method as claimed in claim 1 wherein the said parameter readings are equal to the summation of actual reading captured by the automated system and factor derived from master breaker when put inside the test cavity of the test station.
3. Method as claimed in claim 1 wherein the circuit breaker movement is only restricted to X-Y direction during its mounting in the test cavity of the test station.
4. Method as claimed in claim 1 further comprising step of checking position of trip alarm contact in TRIP and/or ON state.

5. Method as claimed in claim 1 further comprising step of checking UV resetter position of the circuit breaker.
6. A method of testing circuit breakers comprising simulating the functioning of accessories through the measurement of criticai parameters in the breaker responsible for the functioning of accessories.
7. An improved automated system for testing parameters of a moulded case circuit breaker responsible for the functioning of internal accessories, said system comprising :
loading station means for loading circuit breaker to be tested in a test
cavity at test station such that the circuit breaker is always positioned
at the same position;
measurement modules for measuring initial parameters of the circuit
breaker;
means for determining position of UV resetter assembly during TRIP to
RESET operation;
plurality of probe means for determining position of driveshaft between
ON and OFF position of the circuit breaker;
means for determining.trip force of the circuit breaker during ON to
TRIP operation;
controller means for comparing the said parameter readings with a
predetermined band so as to predict the parameters which are closer
to critical values of the band.
8. System as claimed in claim 7 further comprising a plurality of butting pin
means adapted to ensure said circuit breaker movement being restricted
to Z axis.

9. System as claimed in claim 7 further comprising a substantially C shaped bracket means adapted for simulating ROM condition in said circuit breaker.
10. System as claimed in claim 7 further comprising a ball screw means operatively attached to said C shaped bracket means.
11. System as claimed in claim 10, wherein said ball screw means being operated by a motor means.
12. System as claimed in claim 7, wherein said measurement modules comprises a continuity module, a trip force measurement module, a driveshaft module and a TAC actuator measurement module.
13. An improved automated system and a method for testing parameters of a moulded case circuit breaker responsible for the functioning of internal accessories as herein substantially described and illustrated with reference to the accompanying drawings.