JPH06120002A - Resistor for testing generator - Google Patents

Abstract

PURPOSE:To obtain a resistor for testing of generator with which a resistance value can be stabilized for a long period and measuring data can be measured accurately and continuously. CONSTITUTION:A plurality of almost tabular resistor elements 8, which are meanderingly formed, are stacked, they are electrically series-connected, and a tap 12 is interconnected to the intermediate resistor element 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a generator test resistor.

[0002]

2. Description of the Related Art Conventionally, in an output (performance) test of a stationary power generation facility or a portable generator with an engine, the same number of phases as the number of phases of the generator is stored in a tank filled with salt water as a resistor. The test was conducted while adjusting the resistance by suspending the electrode and moving the electrode up and down to change the flooded area.

[0003]

However, the current density in the salt water in the vicinity of the electrodes is extremely high, the salt water in this portion boils in a short time and the resistance value becomes unstable, and only instantaneous performance can be measured. In addition, there is a drawback that accurate data cannot be obtained and reproducibility is poor.

[0004]

Therefore, in the present invention, a large number of substantially plate-shaped resistance elements formed in a meandering shape are stacked and electrically connected in series, and a tap is connected to a resistance element in the middle. The purpose of the present invention is to provide a resistor for generator testing.

[0005]

Embodiments of the present invention will be described in detail with reference to the drawings.
In FIG. 1, A indicates a tester for measuring the performance of a three-phase AC generator, in which a case 2 having a substantially rectangular parallelepiped shape is mounted above the base 1, and three resistances are placed inside the case 2. Body 3
2 sets and a cooling fan 4 are housed, and an input terminal 6 for connecting to a measurement controller 5 and a generator to be tested and an outlet 7 for connecting a jumper cord are stored on the outer surface of the case 2. It is arranged.

As shown in FIGS. 2 and 3, the resistor 3 is formed by stacking a large number of resistance elements 8 formed in a meandering rectangular shape at a predetermined interval to form one grid-shaped resistor. is doing.

Three bolt insertion holes 8a are formed in the resistance element 8, and an insulating bolt 9 for assembly is inserted in the insertion hole 8a. The surface of the bolt 9 is insulated. Has been baked for mica.

In the figure, 10 is an insulating ring formed in an annular shape, and 11 is a conducting ring. Of the three insulating bolts 9, the central insulating bolt 9 is insulated at all intervals of the resistor elements 8 that are stacked. The ring 10 and the remaining two insulation bolts 9 on both ends are alternately inserted with the insulation ring 10 and the conduction ring 11 at the same intervals, so that the resistance elements 8 that are stacked are connected in an electrically series state. .

Further, the resistance element 8 in the middle of stacking,
A plurality of taps 12 are arranged in series so that the current can pass from the middle of the resistor 3.

Then, three such resistors 3 are arranged in upper and lower three stages close to the inner surface of the case 2, one end of each resistor 3 is connected to the leftmost outlet 7, and the other end is connected to a star. It is connected to the input terminal 6 via the delta starter 13. In addition, this circuit is branched between the input terminal 6 and the star / delta starter 13 and connected to the intermediate outlet 14, and a removable jumper cord 15 is interposed between the intermediate outlet 14 and the outlet 7. It is installed and both outlets 14 and 7 are connected. The resistors 3 can be arranged side by side in three rows. In this case, each resistor 3
Will be placed upright and arranged in three rows.

The star / delta starter 13 comprises a star connection contact MSY1 and a delta connection contact MSΔ1 so that both contacts are not closed at the same time.

The resistance circuits R1 and R2 are connected to the input terminal 6 in parallel.

The measurement controller 5 is provided with a start / stop push button switch 5b, a voltmeter 5c, and a frequency meter 5d on the front door 5a.
A control circuit 5e shown in FIG. 6 is arranged inside.

In FIG. 6, T is a timer and the same contact, MSΔ
1, MS △ 2 are relays and contacts of delta connection, MSY
1, MSY2 are relays and contacts of star connection, PB1,
PB2 is a start push button switch, CB1 and CB2 are stop push button switches, 5d is a frequency meter and contacts, TS is a tumbler switch and its contacts, AR is a holding relay and contacts E1 and E.
Reference numeral 2 denotes a power source, which is connected to a point that is not affected by the measured generator switching.

The taps 12 provided on the resistor 3 are connected to the outlets 7a, 7b, 7c, respectively, and different electric resistances can be obtained by changing the jumper cords 15. .

The embodiment of the present invention is constructed as described above, and when a generator (not shown) whose performance is to be tested is connected to the input terminal 6 and the start push button switch PB1 is pressed to close the contact, the timer T At the same time as starting up, it is connected to the generator in a star connection state and heat is generated by the current flowing through each resistor 3 to reach the so-called saturation temperature at which the change in resistance value with respect to temperature change becomes extremely small. Further, the timer T started at the same time as energization is set in advance to a time slightly longer than the time to reach the saturation temperature, and when the set time is reached, the relay MSY1 for star connection is opened, and
Delta connection relay MS △ 1 is closed and each resistor 3
Is connected to the generator in a delta connection.

With the power of the generator measured as described above, first, preheating is performed until the resistance value of each resistor 3 becomes stable at the power of the star connection, that is, about 60% of the power of the delta connection, By automatically switching to the delta connection by the preheating end timer T and performing the measurement, stable performance measurement becomes possible.

By changing the jumper cord 15, the resistance value of each resistor 3 can be increased or decreased stepwise.
In this embodiment, each outlet 7 of each resistance circuit R1, R2
Each tap 12 is connected to a, 7b, 7c so that the resistance value is 75,100,125KVA, which is suitable for power measurement.
Turn on the tumbler switch TS so that both resistance circuits R1
When R2 is placed in parallel, it is possible to measure power of 150, 200, 250 KVA.

[0019]

According to the present invention, since a solid resistor is used, the resistance value is stable for a long time, the measurement data is accurate, and continuous measurement can be performed. You can get good data. Also, by forming the resistance element in a meandering plate shape and stacking them, the outer shape can be made smaller, the device can be made compact and easy to move, and the flow of cooling air of the resistance element can be improved. Further, there is an effect that the resistance value corresponding to the capacity of the generator to be tested can be obtained by connecting the taps to the resistance element in the middle of the stacking.

[Brief description of drawings]

FIG. 1 is an overall side view of a generator tester having a resistor according to the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is a front view of a resistance element.

FIG. 4 is a side view of a resistor.

FIG. 5 is a resistance circuit diagram.

FIG. 6 is a control circuit diagram.

FIG. 7 is a front explanatory view of a resistor according to another embodiment.

[Explanation of symbols]

 8 resistance element 12 taps

Claims (1)

[Claims] 1. A plurality of substantially plate-shaped resistance elements (8) formed in a meandering shape are stacked and electrically connected in series, and a tap (12) is connected to a middle resistance element (8). Naruto generator test resistor.