Meter apparatus having three-phase judgment function

A meter apparatus having three-phase judgment function includes a control unit, a multimeter measurement unit electrically connected to the control unit, a three-phase judgment unit electrically connected to the control unit, a first measurement jack electrically connected to the multimeter measurement unit and the three-phase judgment unit, a second measurement jack electrically connected to the multimeter measurement unit and the three-phase judgment unit, and a third measurement jack electrically connected to the multimeter measurement unit and the three-phase judgment unit.

FIELD OF THE INVENTION

The present invention relates to a meter apparatus, and especially relates to a meter apparatus having three-phase judgment function.

DESCRIPTION OF PRIOR ART

Multimeters and clamp meters are both common electronic measurement apparatuses. A clamp meter measures current in a conductor (for example, an electric wire) without having to make electrical connection.

Measuring three-phase of power and rotation direction of a three-phase motor is very important for motor technology. Incorrect connection between power and motor might damage the motor. However, most of the apparatuses with measuring three-phase of power and rotation direction of three-phase motor functions are complicated and not integrated (because the electricity value of power is very large, but electricity value of the three-phase motor is very small). Therefore, it is very important to design a simple and integrated apparatus with measuring three-phase of power and rotation direction of three-phase motor functions.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned problems, an object of the present invention is to provide a meter apparatus having three-phase judgment function.

In order to achieve the object of the present invention mentioned above, the meter apparatus having three-phase judgment function of the present invention includes a control unit, a multimeter measurement unit electrically connected to the control unit, a three-phase judgment unit electrically connected to the control unit, a first measurement jack electrically connected to the multimeter measurement unit and the three-phase judgment unit, a second measurement jack electrically connected to the multimeter measurement unit and the three-phase judgment unit, and a third measurement jack electrically connected to the multimeter measurement unit and the three-phase judgment unit.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows a block diagram of the first embodiment of the meter apparatus having three-phase judgment function of the present invention. The meter apparatus10having three-phase judgment function of the present invention includes a control unit102, a multimeter measurement unit104, a three-phase judgment unit106, a first measurement jack108, a second measurement jack110, a third measurement jack112, and a display unit132. The three-phase judgment unit106is used to judge the three-phase of power (not shown inFIG. 1) or rotation direction of a three-phase motor (not shown inFIG. 1).

The three-phase judgment unit106includes a first resistor114, a second resistor116, a third resistor118, a fourth resistor120, a switch subunit122, a first comparator124, a first reference voltage subunit136, a second comparator128, and a second reference voltage subunit138.

The control unit102is electrically connected to the multimeter measurement unit104, the display unit132, the output side of the first comparator124, the output side of the second comparator128, and the switch subunit122.

The first measurement jack108is electrically connected to the multimeter measurement unit104and one side of the first resistor114. The second measurement jack110is electrically connected to the multimeter measurement unit104and one side of the third resistor118. The third measurement jack112is electrically connected to the multimeter measurement unit104and the switch subunit122. The switch subunit122is electrically connected to the other side of the second resistor116and the other side of the fourth resistor120.

The first input side of the first comparator124is electrically connected to the other side of the first resistor114and one side of the second resistor116. The second input side of the first comparator124is electrically connected to the first reference voltage subunit136. The first input side of the second comparator128is electrically connected to the other side of the third resistor118and one side of the fourth resistor120. The second input side of the second comparator128is electrically connected to the second reference voltage subunit138.

The meter apparatus10having three-phase judgment function is, for example, a multimeter or a clamp meter. The multimeter measurement unit104is a circuit for measuring resistors, voltages, or currents etc. The first measurement jack108, the second measurement jack110, and the third measurement jack112are used to connect to power or the three-phase motor to measure three-phase of power or the rotation direction of the three-phase motor. The display unit132is used to display the measurement results of the three-phase of power or the rotation direction of the three-phase motor.

The switch subunit122is controlled by the control unit102to control the second resistor116and the fourth resistor120to have no electrical connection with the third measurement jack112when the rotation direction of the three-phase motor is measured by the meter apparatus10.

FIG. 4shows a diagram of an embodiment of the meter apparatus having three-phase judgment function of the present invention (multimeter).FIG. 5shows a diagram of another embodiment of the meter apparatus having three-phase judgment function of the present invention (clamp meter). The circuit design of the meter apparatus10is simple and integrated. The meter apparatus10can measure the three-phase of power or the rotation direction of the three-phase motor, and has the functions of the multimeter as well.

FIG. 2shows a block diagram of the second embodiment of the meter apparatus having three-phase judgment function of the present invention. The meter apparatus10having three-phase judgment function of the present invention includes a control unit102, a multimeter measurement unit104, a three-phase judgment unit106, a first measurement jack108, a second measurement jack110, a third measurement jack112, and a display unit132. The three-phase judgment unit106is used to judge the three-phase of power (not shown inFIG. 2) or rotation direction of a three-phase motor (not shown inFIG. 2).

The three-phase judgment unit106includes a first resistor114, a second resistor116, a third resistor118, a fourth resistor120, a first comparator124, a first variable reference voltage subunit126, a second comparator128, and a second variable reference voltage subunit130.

The control unit102is electrically connected to the multimeter measurement unit104, the display unit132, the output side of the first comparator124, the output side of the second comparator128, the first variable reference voltage subunit126, and the second variable reference voltage subunit130.

The first measurement jack108is electrically connected to the multimeter measurement unit104and one side of the first resistor114. The second measurement jack110is electrically connected to the multimeter measurement unit104and one side of the third resistor118. The third measurement jack112is electrically connected to the multimeter measurement unit104, the other side of the second resistor116, and the other side of the fourth resistor120.

The first input side of the first comparator124is electrically connected to the other side of the first resistor114and one side of the second resistor116. The second input side of the first comparator124is electrically connected to the first variable reference voltage subunit126. The first input side of the second comparator128is electrically connected to the other side of the third resistor118and one side of the fourth resistor120. The second input side of the second comparator128is electrically connected to the second variable reference voltage subunit130.

The meter apparatus10having three-phase judgment function is, for example, a multimeter or a clamp meter. The multimeter measurement unit104is a circuit for measuring resistors, voltages, or currents etc. The first measurement jack108, the second measurement jack110, and the third measurement jack112are used to connect to power or the three-phase motor to measure three-phase of power or the rotation direction of the three-phase motor. The display unit132is used to display the measurement results of the three-phase of power or the rotation direction of the three-phase motor.

The voltage levels of the first variable reference voltage subunit126and the second variable reference voltage subunit130are controlled by the control unit102when the rotation direction of the three-phase motor is measured by the meter apparatus10.

FIG. 4shows a diagram of an embodiment of the meter apparatus having three-phase judgment function of the present invention (multimeter).FIG. 5shows a diagram of another embodiment of the meter apparatus having three-phase judgment function of the present invention (clamp meter). The circuit design of the meter apparatus10is simple and integrated. The meter apparatus10can measure the three-phase of power or the rotation direction of the three-phase motor, and has the functions of the multimeter as well.

FIG. 3shows a block diagram of the third embodiment of the meter apparatus having three-phase judgment function of the present invention. The meter apparatus10having three-phase judgment function of the present invention includes a control unit102, a multimeter measurement unit104, a three-phase judgment unit106, a first measurement jack108, a second measurement jack110, a third measurement jack112, and a display unit132. The three-phase judgment unit106is used to judge the three-phase of power (not shown inFIG. 3) or rotation direction of a three-phase motor (not shown inFIG. 3).

The three-phase judgment unit106includes a first resistor114, a second resistor116, a third resistor118, a fourth resistor120, a switch subunit122, and a third comparator134.

The control unit102is electrically connected to the multimeter measurement unit104, the display unit132, the output side of the third comparator134, and the switch subunit122.

The first measurement jack108is electrically connected to the multimeter measurement unit104and one side of the first resistor114. The second measurement jack110is electrically connected to the multimeter measurement unit104and one side of the third resistor118. The third measurement jack112is electrically connected to the multimeter measurement unit104and the switch subunit122. The switch subunit122is electrically connected to the other side of the second resistor116and the other side of the fourth resistor120.

The first input side of the third comparator134is electrically connected to the other side of the first resistor114and one side of the second resistor116. The second input side of the third comparator134is electrically connected to the other side of the third resistor118and one side of the fourth resistor120.

The meter apparatus10having three-phase judgment function is, for example, a multimeter or a clamp meter. The multimeter measurement unit104is a circuit for measuring resistors, voltages, or currents etc. The first measurement jack108, the second measurement jack110, and the third measurement jack112are used to connect to power or the three-phase motor to measure three-phase of power or the rotation direction of the three-phase motor. The display unit132is used to display the measurement results of the three-phase of power or the rotation direction of the three-phase motor.

The switch subunit122is controlled by the control unit102to control the second resistor116and the fourth resistor120to have no electric connection with the third measurement jack112when the rotation direction of the three-phase motor is measured by the meter apparatus10.

FIG. 4shows a diagram of an embodiment of the meter apparatus having three-phase judgment function of the present invention (multimeter).FIG. 5shows a diagram of another embodiment of the meter apparatus having three-phase judgment function of the present invention (clamp meter). The circuit design of the meter apparatus10is simple and integrated. The meter apparatus10can measure the three-phase of power or the rotation direction of the three-phase motor, and has the functions of the multimeter as well.