JPS60111166A - High frequency digital display setting device - Google Patents

Abstract

PURPOSE:To enable the titled device to display voltage, current,, power, reactive power, etc. with light and small-sized constitution, by storing the function required for measurement and control, in one case which can be fixed to a distributing board, and displaying digitally various measured values, upper limit and lower limit values, etc. CONSTITUTION:A measuring input passing through an auxiliary transformer 1 and an auxiliary current transformer 2 is converted to a DC output corresponding to the voltage, current, power, reactive power, etc. by a converting circuit 3, compared with each upper and lower limit DC output from a setting circuit 4 by a comparator 6, and a control output is generated. On the other hand, the output of the circuit 3 and the output of the circuit 4 and supplied through a measured value set value switching circuit 5, scaling circuit 7, measuring quantity changeover switch 8 and an A/D converter 9; and a measured extent and a setting limit extent are displayed on a digital indicator 10. These respective measurement and control function parts are contained in one case which can be fixed to a distributing board, and since a meter, etc. are not used, a digital display of a high frequency data is executed with simple and small-sized constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides voltage,
In addition to digitally displaying the measured values of multiple measured quantities such as current, power, and reactive power, the upper or lower limit of the measured value of each measured quantity can be set in advance and the values of voltage or current etc. can be automatically monitored. The present invention also relates to a device for automatically controlling the operating status of mechanical equipment, furnaces, etc. using upper and lower limit signals of power, and automatically improving the power factor of a circuit using upper and lower limit signals of reactive power.

After converting the measured values of multiple measured quantities such as current, power, and reactive power into DC output (voltage or current), select the measured DC output of the required measured quantity with a changeover switch, perform A/D conversion, and convert it into a digital output. It relates to displaying and setting the upper or lower limit value of each measured quantity in advance, and taking out as a signal such as voltage (or non-voltage contact) output when the measured value of each measured quantity exceeds the upper or lower limit set value.

b. Description of the prior art Conventionally, when managing the load status of electric circuits that use high frequencies, such as in melting furnaces, amperometric type, thermoelectric type indicating meters, meter relays, etc. are often used to control voltage and current. 2 electric power,
For various measured quantities such as reactive power, it is necessary to read the indicated values of individual indicating instruments or meter relays, or to vary the set values of each meter relay.

From an economical and strength standpoint, the current force needle type type requires more manufacturing man-hours and VA consumption, while the thermoelectric type has good scale linearity (not good) and is weak against electrical strength ( In addition, the comprehensive in-panel wiring facilities are also expensive.In addition, the ones used as a setting device require a large amount of money to manufacture a scale plate exclusively for setting and adjust the corresponding circuit, High accuracy cannot be expected for value reading, and multi-rotation potentiometer type settings from 0 to 100% require reading conversion, and the potentiometer itself needs to have good linearity and is expensive, and digital switch type Analog comparators also require a D/A converter, and digital comparators require an A/D converter, and each component is expensive, requires many additional circuit components, and takes time to assemble and adjust.

The disadvantage was that it required a lot of time.

C1 Purpose of the invention In order to eliminate these drawbacks, the present invention provides a case that can be fixed to a power distribution board to provide voltage and current information.

It stores the functions necessary for measuring and controlling multiple measured quantities such as electric power and reactive power, and simply connects the two inputs of voltage and current to the input section as measurement inputs, and the rest is done by operating the changeover switch. You can freely select and digitally display the skate song measurement value of each measured value, and also set the setting method to output the upper or lower limit signal for each measurement value by operating the selector switch. Adjust the setting variable resistor while looking at the digital display that displays the scaled value for each quantity.
You can freely set the desired setting value. The purpose is to achieve these functions with high precision even when using a large number of parts with few restrictions, - easy assembly and adjustment, and a small size and light weight.

Structure and operation of the invention FIG. 1 is a front view of an embodiment according to the invention, and the front panel section αυ includes a display 01' that switches and displays measured values and set values, and a measured value, upper limit set value, and lower limit set value. Measured value-setting value changeover switch (5γ) to change the measured value and setting value, measurement value changeover switch (8γ) to change the measured value of each measured value and each setting value, and a card to write and store the required upper and lower limit setting values on the card. Holder a4), upper limit operation indicator lamp (6), and lower limit operation indicator lamp a are attached.Furthermore, card holder 0 is attached to lid αG, and upper limit corresponding to each measured quantity is installed inside lid OQ. A variable resistor <4'f that changes the lower limit set value is installed, and the positive variable resistor can be easily adjusted from the outside by opening the lid QQ, so all measurements and settings can be done from the front. It is possible to change the value, select the required measurement quantity, and vary the upper and lower limit set values.

FIG. 2 is a block diagram of the internal functions of an embodiment according to the invention. Voltage input from a single-phase high-frequency circuit is input to one auxiliary transformer (1), and current input is input to one auxiliary current transformer (2). Simultaneously converts voltage, current, power, and reactive power into DC output (voltage or current) from multiple electronic components such as diodes, operational amplifiers, capacitors, and resistors that are attached to a single printed circuit board. It is connected to the human power part of the conversion circuit (3) to convert each measurement value into a DC output (voltage or current). The converted DC output is connected to the input part of a measured value/set value switching circuit (5) that simultaneously switches and outputs each measured value and soil/lower limit set value for each measured quantity, and also connects the converted DC output to the input part of a measured value/set value switching circuit (5). Also connect to the input section of 6).

On the other hand, the DC output from the setting circuit (4) that outputs DC output corresponding to the upper and lower limit set values corresponding to the measured values of each measured quantity is also input to the input section of the measured value-set value switching circuit (5). It is also connected to the input section of the comparator circuit (6). Next, each DC output is converted from the measured value-set value switching circuit (5) into easy-to-read measured values and set values converted by the transformation ratio of the main transformer for measurement of the high frequency circuit and the current transformation ratio of the main transformer for measurement. A scaling circuit (
Connect to the input section of 7). Next, the scaling circuit (
7) Input the scaled DC output for each measured quantity and select and extract the required DC output for one measured quantity.
Each DC output of the scaling circuit (7) is connected to the input part of the measurement quantity changeover switch (8). Measuring amount selection switch (
Connect the DC output from 8) to one A/D converter (9) to convert the analog value into a scaled digital value and display the digital output from the A/D converter (9) digitally. Connect to the digital display OQ by selecting the required measured value scaled in this way and the upper and lower limit set values using the measured value-set value switching circuit (5) and the measured quantity selection switch (8). I am trying to display it in .

For example, when changing the upper limit set value of the measured quantity power, first select the power item with the measured quantity changeover switch (8), then select the changeover switch (5'f) of the measured value-setting value changeover circuit (5).
When the upper limit set value is selected in , the digital display 00 comes to display the upper limit set value of power. Next, open the lid aO,
Internal power variable resistor for setting two limits. .

The resistor (4)' is adjusted to the required setting value by varying it while looking at the digital display 01. Card holder α after adjustment
"I just set the upper limit setting value card for the power item of a"
Enter the second limit setting value. Similarly, if you write the lower limit setting value in the card holder (14) and store it, if you want to know each of the lower limit setting values at the same time, you can do so by looking at this card. Become.

On the other hand, the comparator circuit (6) is connected to the conversion circuit (3) as described above.
) and each set DC output from the setting circuit (4), and when the measured value falls within the upper limit set value range, an ON signal is output, and when it falls below the upper limit set value, an OFF signal is output.
F signal, or ON signal when the measured value is below the lower limit setting value,
A signal that becomes an OFF signal when it exceeds the lower limit setting value.
, it is taken out to the outside as a voltage (or non-voltage contact) output to enable upper and lower limit control.

Other Embodiments In the above explanation, we have described how to use it fixed to a switchboard, etc. However, if the case is made portable, it can be used as a measuring instrument that can be freely measured on site, and can measure voltage or non-voltage upper and lower limit signals. It is also possible to control the load and input each DC output from the conversion circuit or the digital output from the A/D converter to an external printing device for printing and recording.

The measurement of single-phase high-frequency circuits has been described above, but measurement inputs such as generator field DC current or commercial frequency voltage and current related to the high-frequency circuit are added to this device and input.
A conversion circuit that converts these measurement inputs into easy-to-measure DC outputs (voltage or current) is added in the same case, and a setting circuit (4 ), and by adding functions to each of the measured value-setting value switching circuit (5), comparator circuit (6), scaling circuit (7), and measured quantity selection switch (8), the added measurement Digital display and upper/lower limit setting control are also possible for input.

f1 Effects of the Invention As described above, when measuring multiple quantities such as voltage, current, power, and reactive power in a single-phase high-frequency circuit, the present invention uses one auxiliary transformer for voltage input and one auxiliary transformer for current input. For example, it is possible to simultaneously output DC output (voltage or (current), the auxiliary transformer and auxiliary current transformer have extremely small capacity and can be made compact. Furthermore, the device can be constructed with one small auxiliary transformer, one small auxiliary current transformer, and one small printed circuit board containing a conversion circuit, which are configured to exchange each measured value into a DC output. are small and light in weight, and wiring between them is extremely simple. Next, when varying the upper and lower limit set values of each measurement quantity, the soil and lower limit setting DC output of the aforementioned setting circuit is changed to the measured value - set value switching circuit.

Scale circuit, measurement quantity selection switch.

Because the display through one A/D converter allows you to obtain the values corresponding to the predetermined measured values and the capacity/lower limit set value of the setting circuit while looking at the display with the same scaling value and resolution. The variable resistor in the setting circuit is only limited by resolution and setting stability, and even if it is not limited by linearity or other accuracy, it does not affect the setting accuracy of the device in principle, so it is an inexpensive and small variable resistor. Highly accurate upper/lower limit control is possible even when using a device, and assembly and adjustment of the setting circuit becomes easy. In addition, the required display items of this device can be selected using the aforementioned measured value-setting value switching circuit and measured quantity selection switch and can be achieved with one A/D converter and one display, so the panel area can be reduced. Demonstrates the required functionality with a small number of parts. As described above, according to the device of the present invention, the entire device can be made small and light in weight, assembly and adjustment are easy, and the required performance can be achieved without using expensive parts with many restrictions. Extremely large.

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of the present invention, and FIG. 2 is a block diagram of internal functions of the embodiment of the present invention. 1 ..... Auxiliary transformer 2 ..... Auxiliary current generator 3 ..... Conversion circuit for voltage, current, power, reactive power, etc. 4 ..... Setting circuit 4' ...... Variable resistor 5 ...... Measured value-set value switching circuit 5'...
...... Measured value - set value selection switch 6 ...... Comparator circuit 7 ...... Scaling circuit 8.8'... Measured amount selection switch 9 ...
... A/D converter 10.10' ... Digital display 11 ...
... Front panel section 12 ... Upper limit operation indicator lamp 13 ...
... Lower limit operation indicator lamp 14 ... Card holder 15 ... Lid 16 ... Upper and lower limit signals Patent applicant Takemoto Electric Instrument Co., Ltd.

Claims (1)

[Claims] Voltage in a single-phase high frequency (1 to 10 kHz) circuit,
In a device that digitally displays multiple measured quantities such as current, power, and reactive power, and also outputs two or lower limit signals, one auxiliary transformer handles voltage input and one auxiliary transformer handles current input. Current flow device, diode, and arithmetic amplifier rlJ device. A conversion circuit that converts a plurality of measured quantities such as high frequency voltage, current, power, reactive power, etc. into DC output (voltage or current), which is composed of a plurality of electronic components such as capacitors, resistors, etc.; A setting circuit that can adjust and output any setting DC output that corresponds to 3° to each measured DC output (voltage or current) from outside the device, and each measurement DC output from the conversion circuit and the setting circuit. A measured value-set value switching circuit that can input each set DC output and switch each measured value and set value simultaneously from outside the device, compares each measured DC output and each set output, A comparator circuit that outputs an upper or lower limit signal depending on the magnitude of the value, a scaling circuit that digitally converts each input from the measured value to set value switching circuit into an easily readable value, and each input from the measured value to set value switching circuit. A measured quantity changeover switch that can change the measured quantity output from outside the device, one A/D converter that converts an analog value into a digital value, and the A/D converter that converts an analog value into a digital value.
A high-frequency digital display setting device that is equipped with a set of digital displays that display the output from a D converter, and these circuits and components are all housed in one case.