Patent Publication Number: US-8542084-B1

Title: Circuit protection device and trip unit for use with a circuit protection device

Description:
BACKGROUND OF THE INVENTION 
     The present application relates generally to power systems and, more particularly, to a circuit protection device and a trip unit for use with the circuit protection device. 
     At least some known circuit breakers are included within electronic or magnetic trip devices that programmably interrupt a current provided to a load. The trip devices and the circuit breakers may be installed in switchgear or other power distribution systems that may provide electricity to important revenue-generating machinery and/or to machines or devices that are highly desirable to maintain in operation. 
     Some known circuit breakers include a trip mechanism that interrupts a current flowing through the circuit breaker when the current exceeds a current rating of the circuit breaker. For example, some known circuit breakers include a trip bar that is magnetically activated to interrupt the current flowing through the circuit breaker when the rated current is exceeded. However, at least some known circuit breakers exhibit an excessive magnetic flux leakage during operation of the circuit breaker. In addition, vibrations may be induced to the circuit breaker as a result of operating the circuit breaker in an environment including one or more machines. Such vibrations may cause one or more components of the circuit breaker to be dislodged, thus hindering the effective operation of the circuit breakers. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one aspect, a trip unit for use with a circuit protection device including a trip mechanism is provided that includes a support bracket and a magnet member coupled to the support bracket. The magnet member is configured to emit a magnetic field when a current is transmitted through the trip mechanism. The magnet member includes a first side portion, a second side portion, and a rear portion coupled between the first side portion and the second side portion. The trip unit also includes a pivot arm pivotally coupled to the support bracket. The pivot arm includes a first end, a second end, and a curved portion coupled to the first end and the second end. The pivot arm is configured to pivot towards the magnet member to cause the trip mechanism to interrupt the current when the current exceeds a first threshold. 
     In another aspect, a circuit protection device is provided that includes an input terminal configured to receive a current, an output terminal configured to be electrically connected to the input terminal and to transmit the current to at least one load when the output terminal is electrically connected to the input terminal, and a trip mechanism configured to electrically disconnect the input terminal from the output terminal. The circuit protection device also includes a trip bar coupled to the trip mechanism and configured to operate the trip mechanism, and a trip unit positioned about the trip bar. The trip unit includes a support bracket and a magnet member coupled to the support bracket. The magnet member is configured to emit a magnetic field when a current is transmitted through the trip mechanism. The trip unit also includes a pivot arm pivotally coupled to the support bracket. The pivot arm includes a first end, a second end, and a curved portion coupled to the first end and the second end. The pivot arm is configured to pivot towards the magnet member to cause the trip mechanism to interrupt the current when the current exceeds a first threshold. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of an exemplary power system. 
         FIG. 2  is a partial side view of an exemplary circuit protection device that may be used with the power system shown in  FIG. 1 . 
         FIG. 3  is a partial side view of the circuit protection device shown in  FIG. 2  including a trip unit. 
         FIG. 4  is a perspective view of an exemplary trip unit that may be used with the circuit protection device shown in  FIGS. 2 and 3 . 
         FIG. 5  is a perspective view of an exemplary magnet member that may be used with the trip unit shown in  FIG. 4 . 
         FIG. 6  is a perspective view of an exemplary support bracket that may be used with the trip unit shown in  FIG. 4 . 
         FIG. 7  is a perspective view of an exemplary pivot arm that may be used with the trip unit shown in  FIG. 4 . 
         FIG. 8  is a top view of the trip unit shown in  FIG. 4 . 
         FIG. 9  is a flow diagram of an exemplary method of assembling a trip unit that may be used to assemble the trip unit shown in  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Exemplary embodiments of a trip unit and a circuit protection device are described herein. The circuit protection device includes a trip mechanism, a trip bar that activates the trip mechanism, and a trip unit that displaces the trip bar to activate the trip mechanism. The trip unit includes a support bracket, a pivot arm coupled to the support bracket, and a magnet member coupled to the support bracket. A biasing member is coupled to the support bracket and to the pivot arm to bias the pivot arm away from the magnet member. During operation, current flows through the circuit protection device and through the magnet member. The current causes the magnet member to emit a magnetic field that interacts with the pivot arm. If the current exceeds a predetermined current threshold, the strength of the magnetic field overcomes the biasing force exerted on the pivot arm by the biasing member. The pivot arm is pulled towards the magnet member and is maintained in contact with the magnet member. The position of the pivot arm contacting the magnet member facilitates reducing or eliminating a magnetic flux leakage that may otherwise occur in prior art systems. 
     The support bracket includes an upper support member and a lower support member. The pivot arm is coupled to the support bracket such that at least a portion of a body of the pivot arm is positioned between the upper and lower support members. A pivot edge of the pivot arm is positioned to contact a pivot area of the support bracket and to contact a pivot resting surface of the magnet member. Accordingly, the pivot arm is facilitated to be held in position within the trip unit even in the presence of vibrations that may be induced to the circuit protection device. 
       FIG. 1  is a block diagram of an exemplary power system  100 . In an exemplary embodiment, power system  100  includes an electric power source  102 , one or more circuit protection devices  104 , and one or more loads  106 . 
     Electric power source  102  may include, for example, a steam turbine generator, a wind turbine generator, a solar panel array, and/or any other source that generates and/or provides electrical power (i.e., current and voltage) within power system  100 . More specifically, electric power source  102  provides electrical power to loads  106  through circuit protection devices  104 . While a single electric power source  102  is illustrated in  FIG. 1 , it should be recognized that any suitable number of electric power sources  102  may be included within power system  100  and may be coupled to circuit protection devices  104 . 
     In an exemplary embodiment, each circuit protection device  104  is coupled to electric power source  102  to receive power therefrom. Each circuit protection device  104  is also coupled to at least one respective load  106  to protect load  106  from excessive current that may be received from electric power source  102 . More specifically, each circuit protection device  104  is configured to “trip” (i.e., to electrically disconnect electric power source  102  from load  106 ) if the current received from electric power source  102  exceeds one or more thresholds. For example, circuit protection device  104  may trip if the current received exceeds a first current threshold and/or if the current received exceeds a second current threshold for a predetermined amount of time. In one embodiment, circuit protection devices  104  are circuit breakers. Alternatively, circuit protection devices  104  are relays, switchgear, or other devices that are activated to electrically disconnect loads  106  from electric power source  102  when the current received exceeds one or more thresholds. 
     Each load  106  is coupled to a circuit protection device  104  and receives power from electric power source  102  through circuit protection device  104 . In an exemplary embodiment, loads  106  include, without limitation, one or more motors, fans, pumps, computer systems, appliances, and/or any other device or machine that consumes electrical power. 
       FIG. 2  is a partial side view of an exemplary circuit protection device  104  that may be used with power system  100  (shown in  FIG. 1 ).  FIG. 3  is a partial side view of circuit protection device  104  including a trip unit  202 . In an exemplary embodiment, circuit protection device includes an input terminal  204 , an output terminal  206 , a contact arm  208 , a trip mechanism  210 , a trip bar  212 , and trip unit  202 .  FIG. 3  illustrates trip unit  202  substantially enclosing at least a portion of trip bar  212 , while  FIG. 2  illustrates circuit protection device  104  with trip unit  202  omitted to more clearly view trip bar  212 . In addition,  FIG. 3  illustrates circuit protection device  104  including output terminal  206 , while  FIG. 2  illustrates circuit protection device  104  with output terminal  206  omitted. 
     In an exemplary embodiment, input terminal  204  is coupled to electric power source  102  (shown in  FIG. 1 ) and receives electrical current from source  102 . Output terminal  206  is coupled to load  106  (shown in  FIG. 1 ) and transmits current received from electric power source  102  to load  106 . 
     Contact arm  208  is electrically coupled to input terminal  204  and receives current from terminal  204 . Contact arm  208  is raised by trip mechanism  210  to electrically disconnect contact arm  208  (and output terminal  206 ) from input terminal  204 , and is lowered by trip mechanism  210  to electrically connect contact arm  208  (and output terminal  206 ) to input terminal  204 . Current received by contact arm  208  is transmitted to trip unit  202  and to output terminal  206  by a conductor  214 , such as a copper wire. 
     In an exemplary embodiment, trip mechanism  210  is a switch that is operated by trip bar  212  and/or by a user to electrically disconnect input terminal  204  from output terminal  206  and to electrically connect input terminal  204  to output terminal  206 . For example, a user may operate trip mechanism  210  to cause contact arm  208  to be raised to electrically disconnect input terminal  204  from output terminal  206 , and may operate trip mechanism  210  to cause contact arm  208  to be lowered to electrically connect input terminal  204  to output terminal  206 . In addition, if the current received from electric power source  102  through input terminal  204  exceeds one or more thresholds, trip unit  202  may cause trip bar  212  to activate trip mechanism  210 , thus causing trip mechanism  210  to raise contact arm  208  and electrically disconnect input terminal  204  from output terminal  206 . 
     Trip bar  212 , in an exemplary embodiment, is a rigid bar that is coupled to trip mechanism  210 . Trip bar  212  is operated, or displaced, by trip unit  202  to cause trip mechanism  210  to raise contact arm  208 . More specifically, trip unit  202  displaces an upper portion  216  of trip bar  212 , and trip bar  212  pivots about an axis (not shown). A lower portion  218  of trip bar  212  impacts trip mechanism  210  and causes trip mechanism  210  to raise contact arm  208 . 
     In an exemplary embodiment, trip unit  202  displaces upper portion  216  of trip bar  212  when the current received from electric power source  102  through input terminal  204  and contact arm  208  exceeds one or more thresholds. More specifically, if the current received exceeds a first threshold, trip unit  202  causes trip bar  212  to activate trip mechanism  210 . If the current received exceeds a second threshold for a predetermined amount of time, trip unit  202  causes trip bar  212  to activate trip mechanism  210 . In an exemplary embodiment, the first threshold is higher than the second threshold such that trip unit  202  causes trip mechanism  210  to activate (using trip bar  212 ) when a first, substantially instantaneous, current that exceeds the first threshold is received, and also causes trip mechanism  210  to activate when a second current (lower than the first current) is received that persists for a predetermined amount of time. 
       FIG. 4  is a perspective view of an exemplary trip unit  202  that may be used with circuit protection device  104  (shown in  FIG. 2 ). In an exemplary embodiment, trip unit  202  includes a support bracket  302 , a magnet member  304 , a pivot arm  306 , a biasing member  308 , and a deflection bar  310 . 
     In an exemplary embodiment, each of support bracket  302 , magnet member  304 , pivot arm  306 , biasing member  308 , and deflection bar  310  are manufactured from one or more metallic and/or metallic alloy materials. More specifically, in an exemplary embodiment, deflection bar  310  is manufactured from a bimetal material such that a first layer is formed from a first metal and a second layer is formed from a second metal such that deflection bar  310  deflects when heated. Alternatively, support bracket  302 , magnet member  304 , pivot arm  306 , biasing member  308 , and/or deflection bar  310  are manufactured from any other suitable material that enables trip unit  202  to function as described herein. For example, support bracket  302  may be manufactured from a plastic material or another nonconductive material. 
     In an exemplary embodiment, support bracket  302  is coupled to magnet member  304  and is pivotally coupled to pivot arm  306 . Magnet member  304  is also coupled to deflection bar  310 . In addition, pivot arm  306  is biased towards support bracket  302  (and away from magnet member  304 ) by a biasing member  308 , such as a spring. 
     Support bracket  302 , magnet member  304 , pivot arm  306 , and deflection bar  310  at least partially define a cavity  312  within trip unit  202 . In an exemplary embodiment, at least a portion of trip bar  212 , such as upper portion  216  of trip bar  212  (both shown in  FIG. 2 ), is positioned within cavity  312 . 
     During operation, current is received from input terminal  204  (shown in  FIG. 2 ) and is channeled through deflection bar  310  and magnet member  304 . The current causes a magnetic field to be emitted or generated by magnet member  304  and the magnetic field interacts with pivot arm  306 . If the amount of current exceeds a first threshold, a force of the magnetic field causes pivot arm  306  to overcome the biasing force of biasing member  308  and causes pivot arm  306  to be drawn towards magnet member  304 . Pivot arm  306  impacts upper portion  216  of trip bar  212  and displaces upper portion  216 , thus causing trip mechanism  210  to activate. 
     In addition, the current causes deflection bar  310  to heat, and to deflect based on the amount of heat generated by the current. More specifically, a lower portion  314  of deflection bar  310  deflects away from magnet member  304  in an increasing amount as the current transmitted through deflection bar  310 , and the amount of heat generated within deflection bar  310 , increases and/or persists over time. If the current exceeds a second threshold for a predetermined amount of time, lower portion  314  of deflection bar  310  impacts lower portion  218  (shown in  FIG. 2 ) of trip bar  212  and displaces lower portion  218 , thus causing trip mechanism  210  to activate. Accordingly, as described herein, trip unit  202  causes trip mechanism  210  to activate and electrically disconnect input terminal  204  from output terminal  206  if the current received from input terminal  204  exceeds a first threshold and/or if the current received from input terminal  204  exceeds a second threshold for a predetermined amount of time. 
       FIG. 5  is a perspective view of an exemplary magnet member  304  of trip unit  202  (shown in  FIG. 4 ). In an exemplary embodiment, magnet member  304  includes a first side portion  402 , an opposing second side portion  404 , and a rear portion  406  coupled to first side portion  402  and to second side portion  404 , i.e., between first side portion  402  and second side portion  404 . In an exemplary embodiment, each of first side portion  402 , second side portion  404 , and rear portion  406  are manufactured from a conductive material, such as steel or another suitable metal or metallic alloy. In an exemplary embodiment, magnet member  304  is an electromagnet that emits a magnetic field when current is transmitted through member  304 . 
     First side portion  402  includes an upper surface  408  that includes an alignment cavity  410  formed therein. In an exemplary embodiment, alignment cavity  410  is shaped to receive an alignment member (not shown in  FIG. 5 ) of support bracket  302 . In one embodiment, alignment cavity  410  has a substantially semi-circular cross-section. Alternatively, the cross-section of alignment cavity  410  has any other suitable shape configured to receive the alignment member of support bracket  302 . 
     First side portion  402  also includes a pivot resting surface  412  extending from upper surface  408 . Pivot resting surface  412  is substantially planar and cooperates with pivot arm  306  and support bracket  302  to enable arm  306  to pivot towards, and away from, magnet member  304  while facilitating preventing pivot arm  306  from being dislodged from support bracket  302 . In addition, an opening  414  is defined within first side portion  402  for use in coupling magnet member  304  to support bracket  302 . More specifically, a bolt or another coupling mechanism (not shown) is inserted through opening  414  and is coupled to support bracket  302  such that magnet member  304  is maintained in contact with support bracket  302 . 
     Second side portion  404  includes a lower section  416 , and an upper section  418  that forms a magnet arm  420 . In an exemplary embodiment, magnet arm  420  includes a first end  422  and a second end  424 , and a curved portion  426  extending between first end  422  and second end  424 . Magnet arm  420  has a shape that is complementary with, and at least partially conforms to, pivot arm  306  such that at least a portion of pivot arm  306  wraps around curved portion  426  to contact second end  424 , curved portion  426 , and/or first end  422  when pivot arm  306  is fully extended towards magnet arm  420 . In addition, magnet arm  420  facilitates adjusting a force of a magnetic flux that is emitted or generated when current flows through magnet member  304 . More specifically, as current flows through magnet arm  420 , curved portion  426  and second end  424  cause the force of the magnetic flux to be substantially reduced, or “flattened,” proximate to curved portion  426  and second end  424 . 
     First side portion  402 , rear portion  406 , and second side portion  404  at least partially define cavity  312 . In an exemplary embodiment, cavity  312  is sized and shaped to receive at least a portion of trip bar  212 , such as upper portion  216 . More specifically, upper portion  216  of trip bar  212  is positioned within cavity  312  such that, when the current flowing through magnet member  304  exceeds a threshold, pivot arm  306  displaces portion  216  and causes trip mechanism  210  to trip. 
       FIG. 6  is a perspective view of an exemplary support bracket  302  of trip unit  202  (shown in  FIG. 4 ). In an exemplary embodiment, support bracket  302  includes a mounting portion  502  and a retention portion  504  coupled to mounting portion  502 . More specifically, mounting portion  502  is coupled substantially perpendicularly to retention portion  504 . 
     Mounting portion  502  is configured to couple to magnet member  304 , such as to first side portion  402  (both shown in  FIG. 5 ). More specifically, mounting portion  502  includes an opening  506  defined therein that is substantially similar to opening  414  (shown in  FIG. 5 ) of first side portion  402  such that a bolt or another suitable coupling member may be inserted through opening  506  and opening  414  to couple first side portion  402  to mounting portion  502 . 
     Mounting portion  502  also includes an alignment member  508  extending from an inner surface  510  of portion  502 . Alignment member  508  is shaped to substantially match the shape of alignment cavity  410  (shown in  FIG. 5 ). Accordingly, when magnet member  304  is coupled to support bracket  302 , alignment member  508  is positioned within alignment cavity  410  to facilitate aligning magnet member  304  (e.g., first side portion  402 ) with support bracket  302  (e.g., mounting portion  502 ). 
     Retention portion  504  includes an upper support member  512 , a lower support member  514 , and a body  516  extending therebetween. A recess  518  is formed within body  516 . Recess  518  is shaped to receive a portion of pivot arm  306  when pivot arm  306  is biased away from magnet member  304 . Retention portion  504  also includes a biasing anchor  520  that receives an end (not shown) of biasing member  308  (shown in  FIG. 4 ). 
     Upper support member  512  protrudes from body  516  to facilitate retaining pivot arm  306  within support bracket  302  by limiting a movement of arm  306  in an upward direction. Lower support member  514  protrudes from body  516  to facilitate retaining pivot arm  306  within support bracket  302  by limiting the movement of arm  306  in a downward direction. As used herein, the term “upward direction” refers to a direction from lower support member  514  towards upper support member  512 . A “downward direction” refers to a direction from upper support member  512  towards lower support member  514 . 
     Upper support member  512  includes an upper surface  522  and an opposing lower surface  524 , and lower support member  514  includes an upper surface  526  and an opposing lower surface  528 . Pivot arm  306  is positioned between lower surface  524  of upper support member  512  and upper surface  526  of lower support member  514  such that arm  306  is limited from moving in the upward direction and the downward direction. Accordingly, upper support member  512  and lower support member  514  facilitate preventing pivot arm  306  from undesirably being dislodged during operation of trip unit  202 . 
     In an exemplary embodiment, a pivot area  530  is defined at an intersection of mounting portion  502  and retention portion  504 . Pivot area  530  includes a first surface  532  and a second surface  534  intersecting at an angle  536  that is greater than about 90 degrees and that is less than about 180 degrees. In an exemplary embodiment, second surface  534  is substantially parallel with inner surface  510  of mounting portion  502 , and second surface  534  is angled with respect to an inner surface  538  of body  516 . The angled orientation of pivot area  530  (i.e., first surface  532  and second surface  534  intersecting to form angle  536 ) facilitates enabling pivot arm  306  to freely pivot through at least a portion of pivot area  530 . 
       FIG. 7  is a perspective view of an exemplary pivot arm  306  of trip unit  202  (shown in  FIG. 4 ). In an exemplary embodiment, pivot arm  306  includes a first end  602 , a second end  604 , and a curved portion  606  coupled between first end  602  and second end  604 . First end  602  has a shape that substantially conforms to first end  422  of magnet member  304 , second end  604  has a shape that substantially conforms to second end  424  of member  304 , and curved portion  606  has a shape that substantially conforms to curved portion  426  of member  304  such that at least a portion of first end  602 , second end  604 , and curved portion  606  are substantially flush with first end  422 , second end  424 , and curved portion  426 , respectively, of member  304  when pivot arm  306  is maintained in contact with member  304 . 
     In addition, pivot arm  306  includes a retention flange  608  and a retention recess  610  formed between retention flange  608  and second end  604 . A biasing bracket  612  is coupled to an outer surface  614  of pivot arm  306 , and a lower end  616  of pivot arm  306  includes a notched portion  618  formed therein. 
     In an exemplary embodiment, pivot arm  306  is coupled to support bracket  302  (shown in  FIG. 4 ) such that upper support member  512  is positioned within retention recess  610  (i.e., between retention flange  608  and second end  604 ). At least a portion of pivot arm  306  (e.g., the portion of arm  306  between retention recess  610  and notched portion  618 ) is positioned between upper support member  512  and lower support member  514  such that lower support member  514  is positioned within notched portion  618 . A pivot edge  620  of pivot arm  306  is positioned in contact with pivot area  530  (shown in  FIG. 6 ). In an exemplary embodiment, pivot edge  620  is substantially wedge shaped (i.e., a cross-sectional area of pivot edge  620  is substantially shaped as a wedge). When pivot arm  306  is positioned within support bracket  302  and magnet member  304  is coupled to bracket  302 , pivot arm  306  is enabled to pivot about pivot edge  620  and pivot area  530 . 
     Biasing member  308  (shown in  FIG. 4 ) is coupled to biasing bracket  612  and to biasing anchor  520  such that member  308  extends between support bracket  302  and pivot arm  306 . Biasing member  308  biases first end  602  of pivot arm  306  away from magnet member  304 . In one embodiment, biasing bracket  612  includes a plurality of openings  622  for biasing member  308  to couple to for adjusting a biasing force exerted upon pivot arm  306  by member  308 . 
       FIG. 8  is a top view of trip unit  202 . During operation, current is received from input terminal  204  of trip mechanism  210  (both shown in  FIG. 2 ) and is transmitted through magnet member  304  and deflection bar  310 . The current causes a magnetic field to be emitted or generated by magnet member  304 . The magnetic field creates a magnetic force that acts upon pivot arm  306 . In addition, biasing member  308  generates a biasing force that acts upon pivot arm  306  in opposition to the magnetic force. 
     If the biasing force exerted by biasing member  308  is greater than the magnetic force acting on pivot arm  306  as generated by magnet member  304 , pivot arm  306  is pulled away from magnet member  304  in a first rotational direction  702 . However, if the magnetic force is greater than the biasing force, pivot arm  306  is pulled towards magnet member  304  in a second rotational direction  704  such that arm  306  contacts member  304 . More specifically, second end  604  of pivot arm  306  contacts second end  424  of magnet member  304 , curved portion  606  of arm  306  contacts curved portion  426  of member  304 , and/or first end  602  of arm  306  contacts first end  422  of member  304 . Accordingly, a shape of pivot arm  306  at least partially conforms to a shape of magnet member  304  to enable at least a portion of pivot arm  306  to be maintained in contact with magnet member  304  such that a magnetic flux leakage from magnet member  304  is facilitated to be reduced or eliminated. 
     In addition, when pivot arm  306  is pulled towards magnet member  304 , arm  306  contacts upper portion  216  of trip bar  212  (both shown in  FIG. 2 ) and displaces upper portion  216 , thus causing trip mechanism  210  to trip. When the magnetic field is removed and/or when the magnetic force is less than the biasing force, biasing member  308  pulls pivot arm  306  away from magnet member  304  in first rotational direction  702 . 
       FIG. 9  is a flow diagram of an exemplary method  800  of assembling a trip unit that may be used to assemble trip unit  202  (shown in  FIG. 4 ). A substantially L-shaped pivot arm, such as pivot arm  306 , is coupled  802  to a support bracket, such as support bracket  302  (both shown in  FIG. 4 ). More specifically, pivot arm  306  is inserted into support bracket  302  such that upper support member  512  is positioned within retention recess  610  of pivot arm  306  and lower support member  514  is positioned within notched portion  618  of arm  306 . Pivot edge  620  of pivot arm  306  is positioned in contact with pivot area  530 . 
     A substantially U-shaped magnet member, such as magnet member  304  (shown in  FIG. 4 ), is aligned  804  with support bracket  302  by inserting alignment member  508  of support bracket  302  into alignment cavity  410  of magnet member  304 . Magnet member  304  is coupled  806  to support bracket  302  by inserting a bolt or another coupling mechanism through opening  414  (shown in  FIG. 5 ) of magnet member  304  and through opening  506  (shown in  FIG. 6 ) of support bracket  302 . Accordingly, first side portion  402  of magnet member  304  is maintained in contact with mounting portion  502  of support bracket  302 . 
     A biasing member  308  (shown in  FIG. 4 ), such as a spring, is coupled  808  to biasing anchor  520  (shown in  FIG. 6 ) of support bracket  302  and to biasing bracket  612  (shown in  FIG. 7 ) of pivot arm  306 . In one embodiment, a biasing force exerted by biasing member  308  on pivot arm  306  is adjusted by coupling biasing member  308  to biasing bracket  612  through different openings  622  (shown in  FIG. 7 ). 
     Deflection bar  310  (shown in  FIG. 4 ) is coupled  810  to magnet member  304 . Trip unit  202  is positioned  812  about trip bar  212  such that trip bar  212  is positioned within cavity  312  (shown in  FIG. 4 ), and trip unit  202  is coupled  814  to trip mechanism  210 . 
     It should be noted that when trip unit  202  is assembled, pivot arm  306  is free to rotate, or pivot, about pivot edge  620  through at least a portion of pivot area  530  (i.e., through at least a portion of angle  536  (shown in  FIG. 6 )). Pivot arm  306  is limited from moving in an upward direction and a downward direction by upper support member  512  and lower support member  514 . It should also be noted that unless otherwise specified, the order of the steps of method  800  may be interchanged as desired. 
     Exemplary embodiments of a circuit protection device and a trip unit for use with a circuit protection device are described above in detail. The circuit protection device and the trip unit are not limited to the specific embodiments described herein but, rather, components of the device and/or assembly may be utilized independently and separately from other components described herein. Further, the described operations and/or components may also be defined in, or used in combination with, other systems, methods, and/or devices, and are not limited to practice with only the circuit protection device or the trip unit as described herein. 
     Although the present invention is described in connection with an exemplary circuit protection device, embodiments of the invention are operational with numerous other circuit protection devices, or other systems or devices. The circuit protection device described herein is not intended to suggest any limitation as to the scope of use or functionality of any aspect of the invention. In addition, the circuit protection device described herein should not be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the exemplary operating environment. 
     The order of execution or performance of the operations in the embodiments of the invention illustrated and described herein is not essential, unless otherwise specified. That is, the operations may be performed in any order, unless otherwise specified, and embodiments of the invention may include additional or fewer operations than those disclosed herein. For example, it is contemplated that executing or performing a particular operation before, contemporaneously with, or after another operation is within the scope of aspects of the invention. 
     Although specific features of various embodiments of the invention may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the invention, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing. 
     This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.