HK1197563B - Load testing machine - Google Patents

Description

Load testing machine

Technical Field

The present invention relates to a load testing machine for performing an electrical load test on a power supply such as an alternator.

Background

A dry load tester using a resistance unit in which rod-shaped resistors are arranged is proposed.

Patent document 1: japanese unexamined patent application publication No. 2010-25752

However, when the voltage of the power supply as the load test target is large, it is necessary to increase the resistance unit, connect a plurality of resistance units in series, or reduce the voltage of the power supply as the load test target using a transformer. When a plurality of resistance units are connected in series, the number of resistors (or the number of resistor groups having resistors) is large, and therefore, it is complicated to control the number of resistors and the like used in the load test.

Disclosure of Invention

Therefore, an object of the present invention is to provide a load testing machine capable of performing a load test by simple control even when the voltage of a power supply as a load test target is large.

The load testing machine of the present invention includes: first to sixth resistance units; first to sixth cooling fans; insulators disposed between the first to sixth resistance units and the first to sixth cooling fans; and a connection line, each of the first to sixth resistance units being formed of a plurality of resistor groups arranged in a z direction perpendicular to both an x direction and a y direction, the resistor groups being formed by a plurality of rod-shaped resistors parallel to the x direction arranged at predetermined intervals in the y direction perpendicular to the x direction and connected in series, each of the first to sixth cooling fans being provided at a position facing the first to sixth resistance units in the z direction, the first to third resistance units being arranged at intervals equal to or greater than a first distance in the x direction, the fourth to sixth resistance units being arranged at intervals equal to or greater than the first distance in the x direction, the first and fourth resistance units being arranged at intervals equal to or greater than a second distance in the y direction, the second resistance unit and the fifth resistance unit are arranged at an interval of the second distance or more in the y direction, the third resistance unit and the sixth resistance unit are arranged at an interval of the second distance or more in the y direction, the connection line is a cable for connecting in series two or more detachable places of resistor groups adjacent to each other in the y direction, which are resistor groups of two resistance units adjacent to each other at an interval of the second distance or more in the y direction, and the insulator has a magnitude corresponding to a rated voltage of a test target power supply when a power load test is performed by connecting in series the resistor groups of two resistance units adjacent to each other at an interval of the second distance or more in the y direction.

The resistor groups adjacent in the y direction as the resistor groups of the two resistor units are connected in series with each other using a connection line.

In this case, since a resistance value twice as large as that of one resistance cell can be obtained using one resistance cell group, a load test can be performed using one resistance cell group for a power supply having a voltage twice as large as that of a test object power supply for a load test that can be performed using one resistance cell.

For example, when each of the first to sixth resistance units has a specification corresponding to 6600y of a three-phase ac power supply, a load test of the 13200y three-phase ac power supply can be performed by forming 3 resistance unit groups.

Although the voltage applied to one resistance cell group is twice the voltage applied to one resistance cell, the insulator has a specification in consideration of the voltage applied to one resistance cell group, and therefore, even if the voltage applied is twice, insulation from devices around the resistance cells such as the first to sixth cooling fans can be maintained.

Since the connection line connects each of the resistor groups, switching of the resistor groups can be easily controlled at the time of performing a load test, compared to a manner of connecting two resistor units by connecting only one place (one terminal of one resistor).

The first to sixth resistance units and the first to sixth cooling fans preferably consider a power supply voltage of a test subject to be subjected to a load test with one resistance unit. Therefore, compared with a manner in which the number, length, and the like of the resistors are increased, thereby obtaining a specification similar to that which can be obtained using one resistance unit group using one resistance unit, it can be easily realized using an existing product.

Further, by simply removing the connection line from the resistor, only the first to third resistance units (or the fourth to sixth resistance units) can be used, enabling a load test on the low-voltage power supply, as compared to a load test using the connection line.

Preferably, a longitudinal direction of a housing chamber including the first to sixth resistance units, the first to sixth cooling fans, the insulator, and the connection line is parallel to the x direction.

Since the resistor extends in the x direction (the longitudinal direction of the housing chamber), there is little need to change the dimension of the resistor unit in the y direction even if the length of the rod-like member constituting the resistor is extended, and therefore, there is little restriction when the resistor is loaded in a transportation device such as a trailer (or a truck or a lorry) (because of the restriction of the vehicle width in the y direction, when the resistor is extended in the y direction, the resistor cannot be made to be a certain length or more).

Therefore, the storage chamber including the dry load tester can be easily loaded on a transport device such as a trailer (or a truck or a lorry) and moved.

Preferably, the distance between the resistance units adjacent to each other in the y direction is equal to or greater than the second distance, the first distance is longer than the second distance, and the first distance is equal to or greater than 60 cm.

By providing the interval of the first distance or more, the insulation between the resistance units arranged in the x direction is higher than that when the interval is not provided, and the worker can enter between the resistance units, and the work such as wiring (particularly, attachment and detachment of the connection line) is facilitated. By providing the interval of the second distance or more, the insulation between the resistance units arranged in the y direction is higher than that when the interval is not provided.

Preferably, the insulator is disposed between the first resistance unit and the fourth resistance unit, between the second resistance unit and the fifth resistance unit, and between the third resistance unit and the sixth resistance unit.

Although the voltage applied to one resistance cell group is twice as large as the voltage applied to one resistance cell, since the insulator has a specification in consideration of the voltage applied to one resistance cell group, insulation between the resistance cells can be maintained even if the voltage is applied twice. Further, it is possible to prevent the resistance units from colliding with each other due to shaking during transportation or the like.

Preferably, a cylindrical cover for introducing cooling air from the first to sixth cooling fans into the first to sixth resistor units is provided between the first to sixth cooling fans and the first to sixth resistor units, and an upper portion of the cylindrical cover is located inside a case covering a side surface of the lowermost resistor group and spaced from the case by 1cm or more.

Although both the cover and the housing are made of an insulating material, by providing a space so that dust or the like is not accumulated therebetween, insulation can be ensured.

The load testing machine of the present invention includes: first to sixth resistance units; first to sixth cooling fans; insulators disposed between the first to sixth resistance units and the first to sixth cooling fans; and a connection line or a shorting bar, each of the first to sixth resistance units being formed of a plurality of resistor groups arranged in a z direction perpendicular to both the x direction and the y direction, the resistor groups being formed of a plurality of rod-shaped resistors parallel to the x direction arranged at predetermined intervals in the y direction perpendicular to the x direction, each of the first to sixth cooling fans being provided at positions facing the first to sixth resistance units in the z direction, the first to third resistance units being arranged at intervals equal to or greater than a first distance in the x direction, the fourth to sixth resistance units being arranged at intervals equal to or greater than the first distance in the x direction, the first and fourth resistance units being arranged at intervals equal to or greater than a second distance in the y direction, the second resistance unit and the fifth resistance unit are arranged at an interval of the second distance or more in the y direction, the third resistance unit and the sixth resistance unit are arranged at an interval equal to or greater than the second distance in the y direction, the connecting wire or the shorting bar is a connecting member for connecting in series two or more detachable places of resistor groups adjacent in the y direction as resistor groups of two resistor units adjacent to each other at an interval of the second distance or more in the y direction, the insulator has a size corresponding to a rated voltage of a power supply to be tested when a power supply load test is performed using a resistor group in which two resistor units adjacent to each other at an interval of the second distance or more in the y direction are connected in series to form a resistor unit group.

Preferably, the connection between the connection line or the shorting bar and the resistor group is performed by a switching member having a case in which a fixed contact, a movable contact, and a driving member driving the movable contact are built, and which is filled with an inert gas.

If the connection between the connecting wire or the shorting bar and the switching member is performed through the OFF state in which the fixed contact and the movable contact are not in contact with each other, when the user holds the connecting wire or the shorting bar, the risk of electric shock due to leakage current of the resistance unit may be reduced.

Further, since the housing is filled with an inert gas, in an OFF state (or immediately before an ON state) in which the fixed contact and the movable contact are not in contact with each other, there is a low possibility that a spark is generated between the fixed contact and the movable contact.

Preferably, the switching member has a first terminal connected to one of the resistors constituting the resistor group and a second terminal connected to the connection line or the shorting bar, and an insulating wall is provided between the first terminal and the second terminal.

It is possible to prevent erroneous contact with the first terminal when the second terminal is mounted to the connection line or the shorting bar.

Preferably, the switching member has a first wire extending from the inside of the case and connected to one of the resistors constituting the resistor group, and a second wire connected to the connection line or the shorting bar, a region in the inside of the case containing the fixed contact and the movable contact is covered with an inner case, the inside of the inner case is filled with the inert gas, and a region between the case and the inner case containing at least a region between the first wire and the second wire is filled with an insulating substance.

By covering with an insulating substance, a short circuit between the first line and the second line can be avoided.

According to the present invention, there is provided a load testing machine capable of performing a load test by simple control even when the voltage of a power supply as a load test target is large.

Drawings

Fig. 1 is a plan view of a trailer on which a loading platform including the dry load tester of the present embodiment is mounted.

Fig. 2 is a side view of a trailer on which a loading platform including the dry load tester of the present embodiment is loaded.

Fig. 3 is a perspective view showing the structures of the first to sixth resistor units, the frame, the insulator, and the first to sixth cooling fans.

Fig. 4 is a perspective view showing the structures of the first resistance unit, the fourth resistance unit, and the insulator.

Fig. 5 is a rear view showing the structures of the first resistance unit, the fourth resistance unit, and the insulator.

Fig. 6 is a rear view showing the structures of the first resistance unit, the fourth resistance unit, and the insulator when the connection line of fig. 5 is changed to the shorting bar.

Fig. 7 is a perspective view illustrating the structures of the first resistance unit, the fourth resistance unit, and the insulator in a state where connection is made using the switching member.

Fig. 8 is a rear view illustrating the structures of the first resistance unit, the fourth resistance unit, and the insulator in a state where connection is made using the switching member.

Fig. 9 is a perspective view of the switching member.

Fig. 10 is a sectional configuration view of the switching member.

Fig. 11 is a cross-sectional structural view of a switching member having a structure different from that of fig. 10.

Detailed Description

The present embodiment will be described below with reference to the drawings. The dry load tester 1 of the present embodiment includes: the air conditioner includes a frame 10, first to sixth resistor units 21 to 26, first to sixth cooling fans 31 to 36, a connection switching unit 40, an insulator 50, and a connection line 60 (fig. 1 and 5).

The frame 10 has a size to be accommodated in the accommodation chamber 70 of the container (or the large-volume container), and the first to sixth resistance units 21 to 26 are fixed to the frame 10 via the insulator 50. A substrate, vibration-proof insulating rubber, or the like (not shown) may be provided between the insulator 50 and the frame 10.

For the sake of explanation, the traveling direction of a transport device such as a trailer (or a truck or a lorry) on which the storage chamber 70 is mounted (the longitudinal direction of the storage chamber 70) is defined as the x direction, the horizontal direction perpendicular to the traveling direction is defined as the y direction, and the vertical direction perpendicular to both the x direction and the y direction is defined as the z direction.

Each of the first to sixth resistance units 21 to 26 includes a plurality of resistor groups arranged in the z direction and connected in parallel, each of the resistor groups being formed of a plurality of rod-like resistors R arranged in the y direction at predetermined intervals and connected in series in parallel with the x direction. The resistor unit is used to perform a load test of a power supply such as a generator according to a change in a load (voltage) condition of the power supply by switching a resistor group to be used, switching a connection method such as neutral point connection of the first to third resistor units 21 to 23 (or the fourth to sixth resistor units 24 to 26), or switching a connection method of the resistor group.

Although each of the first to sixth resistance units 21 to 26 has 8 resistor groups connected in parallel in the z direction in the present embodiment, each of the resistor groups is formed by 8 rod-shaped resistors R parallel to the x direction arranged at predetermined intervals in the y direction and connected in series using short-circuiting rods or the like, the number of the resistors R arranged in each resistor group and the number of the resistor groups are not limited to the above numbers.

For each resistor group, in order to flow cooling air from a cooling fan provided at a lower portion toward an upper portion, openings are provided at an upper surface and a lower surface, and in order to make insulation with adjacent resistor units high, a case made of an insulating material is used to cover side surfaces.

At least one of the ends of the resistors R connected in series constituting the resistor group (not connected to the connection line 60 described later) is connected to the connection switching unit 40 by a cable (not shown).

In order to make the cooling of the cooling fan more efficient, the resistors R of each resistor group are arranged in the following manner: the resistors R of the resistor group adjacent in the z direction are arranged at intermediate positions between the resistors R constituting the resistor group and the resistors R adjacent to the resistors R in the y direction.

The first to third resistance cells 21 to 23 are arranged at intervals of the first distance d1 or more in the x direction, and the fourth to sixth resistance cells 24 to 26 are arranged at intervals of the first distance d1 or more in the x direction. The first distance d1 is preferably longer than a length (for example, about 60 cm) that separates the resistance units (for example, the first resistance unit 21 and the second resistance unit 22) adjacent in the x direction so as to insulate them, and that allows a worker to enter therebetween to perform work.

The first resistance unit 21 and the fourth resistance unit 24 are arranged at an interval of a second distance d2 or more in the y direction, the second resistance unit 22 and the fifth resistance unit 25 are arranged at an interval of a second distance d2 or more in the y direction, and the third resistance unit 23 and the sixth resistance unit 26 are arranged at an interval of a second distance d2 or more in the y direction. Second distance d2 preferably has a length (e.g., around 11 cm) that is greater than the length separating adjacent resistive elements in the y-direction (e.g., first resistive element 21 and fourth resistive element 24) so that they are insulated.

The first resistance unit 21 and the fourth resistance unit 24 are used for an R-phase load test, the second resistance unit 22 and the fifth resistance unit 25 are used for an S-phase load test, and the third resistance unit 23 and the sixth resistance unit 26 are used for a T-phase load test.

First to sixth cooling fans 31 to 36 are mounted on the upper portion of the inside of the housing 10 and the lower portions of the first to sixth resistance units 21 to 26, respectively, and air inlets of the first to sixth cooling fans 31 to 36 are provided on the side surfaces and the bottom surface of the lower portion of the inside of the housing 10.

Cylindrical covers (first cover 31a to sixth cover 36a) for guiding the cooling air from the first cooling fan 31 to the sixth cooling fan 36 to the first resistance unit 21 to the sixth resistance unit 26 are provided between the first cooling fan 31 to the sixth cooling fan 36 and the first resistance unit 21 to the sixth resistance unit 26. The upper part of the cylindrical cover is located inside the casing covering the side surface of the lowermost resistor group, and is preferably spaced from the casing by 1cm or more. Although both the cover and the housing are made of an insulating material, by providing a space so that dust or the like is not accumulated therebetween, insulation can be ensured.

Each of the first to sixth resistance units 21 to 26 has specifications (the number of resistors R, the resistance value, and the like) corresponding to the rated voltage of the test object power supply at the time of the power supply load test in a state where the resistance units are not connected in series.

For example, each of the first to sixth resistance units 21 to 26 has specifications (the number of resistors R, the resistance value, and the like) corresponding to the rated voltage of the power supply to be tested when a load test of the three-phase ac power supply is performed using 3 resistance units of the first to sixth resistance units 21 to 26.

Each of the first to sixth cooling fans 31 to 36 has specifications (cooling capacity of the fan, etc.) for cooling each of the first to sixth resistance units 21 to 26 when performing the power load test.

The connection switching unit 40 includes a switching device, a control device such as a CPU, and the like, and performs switching of the connection to the test target power supply, switching of the resistor group used for the connection, switching of the connection method of the first to third resistor units 21 to 23 (or the fourth to sixth resistor units 24 to 26) for the connection of the neutral point, and switching of the connection method of the resistor group. By connecting the resistance units in series, a load test of the direct current power supply can be performed.

The insulator 50 is used for insulation between the first to sixth resistance units 21 to 26 to which high voltage is applied and peripheral devices (the frame 10, the first to sixth cooling fans 31 to 36, and the like).

In addition, for the purpose of insulating between the resistance units adjacent in the y direction or preventing the resistance units from colliding with each other due to, for example, shaking during transportation, it is preferable to provide insulators 50 (see fig. 1 and 5) between the first resistance unit 21 and the fourth resistance unit 24, between the second resistance unit 22 and the fifth resistance unit 25, and between the third resistance unit 23 and the sixth resistance unit 26.

When a power load test is performed using two resistor groups of two resistor units (the first resistor unit 21 and the fourth resistor unit 24, the second resistor unit 22 and the fifth resistor unit 25, and the third resistor unit 23 and the sixth resistor unit 26) adjacent to each other with a second distance d2 in the y direction, which are connected in series, as a resistor group, the insulator 50 has specifications (such as a size) corresponding to the rated voltage of the test target power supply. In particular, the dimension of the insulator 50 provided at the lower portion of the resistance unit in the z direction has a length equal to or longer than the second distance d 2.

For example, when a load test of the three-phase ac power supply is performed by connecting in series two resistor groups of two resistor units (the first resistor unit 21 and the fourth resistor unit 24, the second resistor unit 22 and the fifth resistor unit 25, and the third resistor unit 23 and the sixth resistor unit 26) adjacent to each other with the second distance d2 therebetween in the y direction, and using the resistor groups, the insulator 50 has specifications (size and the like) corresponding to the rated voltage of the test target power supply. In particular, the dimension of the insulator 50 provided at the lower portion of the resistance unit in the z direction has a length equal to or longer than the second distance d 2.

That is, the insulator 50 has a specification corresponding to twice the rated voltage of the test object power supply corresponding to the specification of each of the first to sixth resistance units 21 to 26 or the first to sixth cooling fans 31 to 36.

For example, when each of the first to sixth resistance units 21 to 26 has a specification corresponding to a 6600V three-phase alternating-current power supply, the insulator 50 having a specification corresponding to a 13200V three-phase alternating-current power supply is used. In this case, the length of the insulator 50 is several centimeters longer than the specification corresponding to the 6600V three-phase ac power supply.

The connection line 60 is a cable for connecting (the resistors R of) resistor groups adjacent in the y direction, which are two resistor groups of two resistor units adjacent in the y direction with the second distance d2 therebetween, in series at two or more places in a detachable state.

The number of the connection lines 60 is 3 times the number of the resistor groups in the resistor unit (8 groups × 3 — 24 connection lines 60 in the present embodiment), and each of the connection lines 60 connects the following two terminals: among the resistors R constituting the resistor group, a terminal of one resistor R near the resistance unit to be connected; among the resistors R constituting the resistor group of the resistance unit to be connected adjacent to the terminal in the y direction, the terminal of the resistor R close to the terminal.

Although the present embodiment has been described with respect to the manner in which the groups of resistor groups are connected using the connection lines 60, the connection is not limited to the groups, and the connection may be performed using the connection lines 60 at least two places of the plurality of resistor groups. In comparison with a method in which two resistor units are connected in series by connecting only one place (one terminal of one resistor R), switching of the resistor group in the load test can be easily controlled. The more places to connect, the easier the switching control.

Ring terminals (indicated by black circles in fig. 3 and 4) are provided at both terminals of the connection line 60, and the resistor R and the connection line 60 can be detachably connected by holding the ring terminals on the terminals of the resistor R and fixing them with screws (or fixing them with bolts).

The accommodation chamber 70 has an opening and closing door at least at the following positions: positions in the upper surface that are opposed to the first to sixth resistance units 21 to 26; positions in the side surface that oppose the air inlets of the first cooling fan 31 to the sixth cooling fan 36; and a rear surface. The door on the side surface is opened when air is sucked, the door on the upper surface is opened when air is discharged, and the door on the rear surface is opened when an operation (load test operation) of electrically connecting the test object three-phase ac power source or the connection switching section 40 is performed, thereby performing a load test.

The resistor groups of two resistor units adjacent in the y direction are connected in series to each other using a connection line 60.

In this case, since a resistance value twice as large as that of one resistance cell can be obtained using one resistance cell group, a load test can be performed using one resistance cell group for a power supply having a voltage twice as large as that of a test object power supply for a load test that can be performed using one resistance cell.

For example, when each of the first to sixth resistance units 21 to 26 has a specification corresponding to a 6600V three-phase ac power supply, a load test of the 13200V three-phase ac power supply can be performed by forming 3 resistance unit groups.

Although the voltage applied to one resistor unit group is twice the voltage applied to one resistor unit, the insulator 50 has specifications in consideration of the voltage applied to one resistor unit group, and therefore, even if the voltage is applied twice, insulation from devices around the resistor units such as the rack 10 and the first to sixth cooling fans 31 to 36 and insulation between the resistor units can be maintained.

Since the connection line 60 connects each of the resistor groups, switching of the resistor groups can be easily controlled at the time of performing a load test, compared to a manner of connecting two resistor units by connecting only one place (one terminal of one resistor R).

The first to sixth resistance units 21 to 26 and the first to sixth cooling fans 31 to 36 are preferably considered to be the test subject power supply voltage for performing a load test with one resistance unit. Therefore, compared with a manner in which the number, length, and the like of the resistors R are increased, thereby obtaining a specification similar to that which can be obtained using one resistance unit group using one resistance unit, it can be easily realized using an existing product.

Further, since the resistor R extends in the x direction (the longitudinal direction of the housing chamber 70), even if the length of the rod-like member constituting the resistor R is extended, there is little need to change the dimension of the resistance unit in the y direction, and therefore, there is little restriction when loaded in a transportation device such as a trailer (or a truck or a lorry) (because of the restriction of the vehicle width in the y direction, when the resistor R is extended in the y direction, the resistor R cannot be made longer than a certain length).

Therefore, the housing chamber 70 including the dry load tester 1 can be easily loaded on a transport device such as a trailer (or a truck or a lorry) and moved.

Further, by simply removing the connection line 60 from the resistor R, it is possible to use only the first to third resistance units 21 to 23 (or the fourth to sixth resistance units 24 to 26), and it is possible to perform a load test on a low-voltage power supply, as compared with a load test using the connection line 60.

Further, by providing the interval of the first distance d1 or more, the insulation between the resistance elements arranged in the x direction is higher than that when the interval is not provided, and the worker can enter between the resistance elements, and the work such as wiring (particularly, attachment and detachment of the connection line 60) is facilitated. By providing the interval of the second distance d2 or more, the insulation between the resistance cells arranged in the y direction is higher than that when the interval is not provided.

Although in the present embodiment, the description has been made with the resistors R in the resistor group connected in series, a part or all of the resistors R may be connected in parallel by changing the connection method between the end of the resistor R and the end of another resistor R. Therefore, the connection method of the resistors R in the resistor group can be switched to series or parallel by using the shorting bar or using the connection switching section 40. In this case, when there are many places connected in parallel in the resistor group, a load test of the low-voltage three-phase ac power supply can be performed.

Further, although it is described that the resistor group of the resistance unit is connected with the resistor groups of the other resistance units using the connection line 60, the connection member between the resistor groups is not limited to the cable. For example, the resistor group may be connected with other resistor groups using the shorting bar 61 (refer to fig. 6), similar to the shorting bar between the terminals of the connecting resistor R.

In the present embodiment, the connection line 60 or the shorting bar 61 is directly connected to the resistor R, but the connection may be performed by a switching member 80, in which the switching member 80 has a housing 87, and the housing 87 contains a fixed contact 81, a movable contact 83, and a driving member 85 for driving the movable contact 83, and is filled with an inert gas such as nitrogen (see fig. 7 and 10).

Specifically, the switching member 80 includes a fixed contact 81, a movable contact 83, a driving member 85, a lead wire 86, and a case 87, and is provided in the vicinity of a terminal of a resistor R connected to the connection line 60 or the shorting bar 61 in the resistor group.

A terminal (first terminal 81a) of the switching member 80 protruding from one fixed contact 81 to the outside of the case 87 is connected to a terminal of the resistor R, and a terminal (second terminal 81b) protruding from the other fixed contact 81 to the outside of the case 87 is connected to one of the connection line 60 and the shorting bar 61. The connection of the resistor R to the first terminal 81a is always connected, and the connection of the connection line 60 or the shorting bar 61 to the second terminal 81b is connected when connecting the resistance units. In order to prevent the second terminal 81b from being erroneously brought into contact with the first terminal 81a or from being short-circuited between the first terminal 81a and the second terminal 81b when the second terminal 81b is attached to the connection line 60 or the shorting bar 61, an insulating wall 88 (see fig. 9) is preferably provided between the first terminal 81a and the second terminal 81 b.

Movable contact 83 is driven by a driving member 85 and is switched between an ON state in which it is connected to fixed contact 81 and an OFF state in which it is not connected to fixed contact 81. The connection between the connection line 60 or the shorting bar 61 and the second terminal 81b is performed in an OFF state.

The driving member 85 is connected to the connection switching unit 40 through a lead wire 86, and operation control (switching control between an ON state and an OFF state) is performed by the connection switching unit 40.

The housing 87 contains the fixed contact 81, the movable contact 83, and the driving member 85 therein, and is filled with an inert gas.

If the connection between the connection line 60 or the shorting bar 61 and the switching member 80 (the second terminal 81b) is performed by the OFF state in which the fixed contact 81 and the movable contact 83 are not in contact with each other, when the user holds the connection line 60 or the shorting bar 61 by hand, the risk of electric shock due to leakage current of the resistance unit can be reduced.

Since housing 87 is filled with inert gas, there is a low possibility that a spark will occur between fixed contact 81 and movable contact 83 in the OFF state (or immediately before the ON state) in which fixed contact 81 and movable contact 83 are not in contact with each other.

Instead of the first terminal 81a or the second terminal 81b, cables (a first wire 82a and a second wire 82b) protruding from the fixed contact 81 to the outside of the case 87 may be provided (see fig. 11).

One end of the first wire 82a is connected to one of the fixed contacts 81, and the other end of the first wire 82a is connected to the resistor R. One end of the second wire 82b is connected to the other fixed contact 81, and the other end of the second wire 82b is connected to the wire connecting wire 60 or the shorting bar 61.

Inside the case 87, a region of the first wire 82a in contact with the fixed contact 81, a region of the second wire 82b in contact with the fixed contact 81, and a region including the fixed contact 81 and the movable contact 83 are covered with a sealed container (inner case) 90, and the inside of the sealed container 90 is filled with an inert gas such as nitrogen gas. Between the sealed container 90 and the case 87, an insulating member such as butyl rubber is filled in a region including at least a region between the first wire 82a and the second wire 82b in order to prevent a short circuit between the first wire 82a and the second wire 82 b.

In fig. 11, the entire region between hermetic container 90 and case 87 is filled with an insulating member, and the region filled with the insulating member is shown by a grid pattern. The lead wires 86 (not shown in fig. 11) are connected through control terminals 89 extending from the driving member 85.

Although fig. 11 shows that the first wire 82a is formed separately from one fixed contact 81 and the second wire 82b is formed separately from the other fixed contacts 81, they may be formed integrally, and the tip ends of the first wire 82a and the second wire 82b may be brought into contact with the movable contact 83 as a function of the fixed contacts 81.

Description of the reference numerals

1 Dry load tester

10 machine frame

21-26 first to sixth resistance units

31-36 first to sixth cooling fans

31a to 36a first to sixth covers

40 connection switching part

50 insulator

60 connecting line

61 short-circuit bar

70 accommodation chamber

80 switching member

81 fixed contact

81a, 81b first terminal, second terminal

82a, 82b first and second lines

83 Movable contact

85 drive member

86 lead wire

87 case

88 insulating wall

89 control terminal

90 closed container

d1, d2 first distance and second distance

Claims (9)

1. A load tester, comprising:

first to sixth resistance units;

first to sixth cooling fans;

insulators disposed between the first to sixth resistance units and the first to sixth cooling fans; and

a connecting wire is arranged on the base plate,

each of the first to sixth resistance units is composed of a plurality of resistor groups arranged in a z direction perpendicular to both an x direction and a y direction, the resistor groups being formed by a plurality of rod-shaped resistors parallel to the x direction arranged at predetermined intervals in the y direction perpendicular to the x direction and electrically connected in series,

each of the first to sixth cooling fans is provided at a position opposite to the first to sixth resistance units in the z direction,

the first to third resistance units are arranged at intervals of a first distance or more in the x direction,

the fourth to sixth resistance units are arranged at intervals equal to or greater than the first distance in the x direction,

the first resistance unit and the fourth resistance unit are arranged at an interval of a second distance or more in the y direction,

the second resistance unit and the fifth resistance unit are arranged at an interval of the second distance or more in the y direction,

the third resistance unit and the sixth resistance unit are arranged at an interval equal to or greater than the second distance in the y direction,

the connecting wire is a cable for electrically connecting in series two or more places, in a detachable state, resistor groups adjacent in the y direction, which are resistor groups of two resistor units adjacent to each other with an interval of the second distance or more in the y direction,

the insulator has a size corresponding to a rated voltage of a power supply to be tested when a power supply load test is performed by electrically connecting resistors of two resistance units adjacent to each other with an interval of the second distance or more in the y direction in series to form a resistance unit group.

2. The load testing machine according to claim 1, wherein a longitudinal direction of a housing chamber containing the first to sixth resistance units, the first to sixth cooling fans, the insulator, and the connection line is parallel to the x direction.

3. The load tester according to claim 1, wherein a space equal to or larger than the second distance is provided for insulating between the resistance units adjacent in the y direction,

the first distance is longer than the second distance, and the first distance is 60cm or more.

4. The load tester of claim 1, wherein the insulator is disposed between the first resistance unit and the fourth resistance unit, between the second resistance unit and the fifth resistance unit, and between the third resistance unit and the sixth resistance unit.

5. The load testing machine according to claim 1, wherein a cylindrical cover for introducing cooling air from the first to sixth cooling fans into the first to sixth resistance units is provided between the first to sixth cooling fans and the first to sixth resistance units,

the upper part of the cylindrical cover is positioned on the inner side of the shell covering the side surface of the lowermost resistor group, and is spaced from the shell by more than 1 cm.

6. A load tester, comprising:

first to sixth resistance units;

first to sixth cooling fans;

insulators disposed between the first to sixth resistance units and the first to sixth cooling fans; and

a connecting wire or a short-circuit bar,

each of the first to sixth resistance units is composed of a plurality of resistor groups arranged in a z direction perpendicular to both an x direction and a y direction, the resistor groups being formed by a plurality of rod-shaped resistors parallel to the x direction arranged at predetermined intervals in the y direction perpendicular to the x direction,

each of the first to sixth cooling fans is provided at a position opposite to the first to sixth resistance units in the z direction,

the first to third resistance units are arranged at intervals of a first distance or more in the x direction,

the fourth to sixth resistance units are arranged at intervals equal to or greater than the first distance in the x direction,

the first resistance unit and the fourth resistance unit are arranged at an interval of a second distance or more in the y direction,

the second resistance unit and the fifth resistance unit are arranged at an interval of the second distance or more in the y direction,

the third resistance unit and the sixth resistance unit are arranged at an interval equal to or greater than the second distance in the y direction,

the connecting wire or the shorting bar is a connecting member for electrically connecting in series two or more places, in a detachable state, resistor groups adjacent in the y direction, which are resistor groups of two resistor units adjacent to each other with an interval of the second distance or more in the y direction,

the insulator has a size corresponding to a rated voltage of a power supply to be tested when a power supply load test is performed using a resistor group in which two resistor units adjacent to each other at an interval of the second distance or more in the y direction are electrically connected in series to form a resistor unit group.

7. The load tester according to claim 6, wherein the connection between the connection wire or the shorting bar and the resistor group is performed by a switching member having a case in which a fixed contact, a movable contact, and a driving member that drives the movable contact are built, and which is filled with an inert gas.

8. The load testing machine according to claim 7, characterized in that the switching member has a first terminal connected to one of the resistors constituting the resistor group and a second terminal connected to the connection wire or the shorting bar,

an insulating wall is provided between the first terminal and the second terminal.

9. The load testing machine according to claim 7, wherein the switching member has a first wire connected to one of the resistors constituting the resistor group and a second wire connected to the connection wire or the shorting bar, extending from the inside of the case,

an area in the interior of the housing containing the fixed contacts and the movable contacts is covered by an inner housing,

filling the inert gas inside the inner shell,

an insulating substance is filled in a region between the case and the inner case including at least a region between the first line and the second line.