How can a three phase four wire meter be reversed? 10

1 Analysis of the reasons for the reversal.

1) It belongs to the electric energy meter metered on both sides of the high-voltage connecting line.

metering device under load.

When the force rate is lower than and the energy meter lacks phase C working voltage, the active energy meter will be reversed, and the actual power should be calculated according to the correction coefficient k.

3) When the voltage phase sequence of the electric energy meter and the phase sequence of the power supply are changed, the reactive energy meter will be reversed.

4) Asynchronous motors that may run at overspeed.

When the motor runs at excessive speed and is connected with other loads in parallel, the motor becomes a generator and can output electric energy to the network, resulting in the reversal of the active energy meter.

5) When measuring the three-phase four-stage active energy meter with three single-phase active energy meters, such as the user-side three-phase capacitor input is unbalanced (or the fuse of a phase capacitor bank.

defects), the power factor of the load.

Under the influence of the change, one of the energy meters will be reversed, while the speed of the other two energy meters will be slightly accelerated, and the actual amount of electricity measured should be the algebraic sum of the three energy meters.

6) In three-phase four-wire.

In the circuit, A-B or B-C and C-A are connected to the 380V welding machine.

When the other phase is not connected to the load or the load is not put in, if the three-phase four-wire active energy meter is used for metering, there will be a negative torque generated by one element; If the measurement uses three single-phase energy meters, there will be a reversal of one energy meter, and the actual measured energy is the algebraic sum of the three meters.

7) When there is a load side"Power factor"When the compensation device is put into operation, in the case of overcompensation, the reactive energy meter will reverse (when there is no inverter), while the active energy meter will rotate forward.

8) Improper adjustment of the electric energy meter will cause reversal, in the verification process of the active energy meter, when the light load error value adjustment is unreasonable, under the no-load or slight electric load, reversal may occur. This happens in both single-phase and three-phase active energy meters.

2 Solving the inversion problem.

1) The electric energy meter that belongs to the measurement on both sides of the contact line should be selected with active and reactive energy meters with inverter stopper, and the installation method of positive and negative meters should be adopted.

2) For metering devices operating at 10kV and above voltage levels, a voltage loss timer should be installed to find the fault of the phase loss voltage operation of the electric energy meter in time, and provide a basis for the recovery of electricity.

3) The three-phase four-wire power supply line should strive to do a good job in load balancing, strengthen the inspection of the user's side force rate compensation device, and eliminate the capacitance fault in time, so that the electric energy meter can operate in a conventional state for a long time.

4) Arresters have been installed in the three-phase four-wire distribution line.

Under the premise of using three-phase four-wire active energy meter and three-phase reactive energy meter for electric energy metering, it can be considered.

5) Overcompensation of the force rate will affect the power system.

The voltage quality is affected to a certain extent, and the load that is overcompensated for the long-term force rate should be selected"Both directions"The metering of reactive energy meters is carried out for force rate assessment, and the user consciously complies with the relevant provisions of force rate compensation by economic means.

6) The error range of each load point should be reasonably controlled in the calibration process of the electric energy meter, and the error value of each sub-component of the three-phase electric energy meter should be consistent, which can prevent the reversal under no load or slight tribute load.

The current inlet and outlet lines are connected in reverse.

Two of them are guided, I remember.

Reasons for the reversal of the three-phase meter:

1: One of the three phases or two or three phases is reversed. Put the corresponding reversed phase in the watt-hour meter.

The inlet and outlet lines can be adjusted down.

That's it. 2: The wiring of the watch is not reversed, but it may be that the load side has a load like a two-phase AC welder, which causes the dial to sometimes be reversed.

There is an inversion phenomenon. This is normal and is generally not treated or used with a bidirectional meter.

3: Forward and reverse contactor.

The coil is reversed, and the line can be replaced back.

The previous electricity meter of two-phase electricity was connected to the wrong one, and it was not clear how it was wrong, so it was reversed.

Summary. Hello, dear, the reversal of the three-phase four-wire meter is generally caused by the following reasons: 1. The installation environment of the meter is improper or the line wiring of the meter is wrong; 2. The overload use of the meter or the installation in the overloaded circuit; 3. The terminal of the meter has poor contact or short circuit; 4. Poor contact with the ground wire of the meter; 5. The load deviation of the meter is large; 6. The load of the meter is unbalanced; 7. Poor grounding of the meter; 8. Poor contact of meter lines; 9. Meter failure; 10. The control circuit of the meter is abnormal.

Hello, dear, the reversal of the three-phase four-wire meter is generally caused by the following reasons: 1. The installation environment of the meter is improper or the line wiring of the meter is wrong; 2. The overload use of the meter or the installation in the overloaded circuit; 3. The terminal of the meter has poor contact or short circuit; 4. Poor contact with the ground wire of the meter; 5. The load deviation of the meter is large; 6. The load reputation of the meter is unbalanced; 7. Poor grounding of the meter; 8. Poor contact of the electric field meter line; 9. Huiji section meter failure; 10. The control circuit of the meter is abnormal.

Hello, dear, the reversal of the three-phase four-wire meter is generally caused by the following reasons: 1. The installation environment of the meter is improper or the line wiring of the meter is wrong; 2. The overload use of the meter or the installation in the overloaded circuit; 3. The terminal of the meter has poor contact or short circuit; 4. Poor contact with the ground wire of the meter; 5. The load deviation of the meter is large; 6. The load reputation of the meter is unbalanced; 7. Poor grounding of the meter; 8. Poor contact of the electric field meter line; 9. Huiji section meter failure; 10. The control circuit of the meter is abnormal.

Kiss, hello! Glad for your question, to make a three-phase four-wire meter reverse, you need to follow the steps below:1

Find the three-phase line of the meter and connect the cables in the order of L1, L2, L3; 2.Find the neutral line of the meter and connect the neutral wire to the neutral terminal; 3.Reverse the phase sequence of the meter, connect L1 to L3, L2 to L1, and L3 to L2; 4.

Reverse the direction of the electricity turbulence of the meter and reverse the direction of the current; 5.Reverse the voltage direction of the meter and reverse the voltage direction; 6.Reverse the magnetic direction of the meter and reverse the magnetic direction; 7.

Reverse the voltage of the meter and the direction of the current to reverse the meter.

Solution: three-phase four-wire system.

In the case of the reversal of the watt-hour meter, one of the three phases or two or three phases is reversed, and the corresponding reversed phase can be replaced at the inlet and outlet lines of the watt-hour meter.

Another situation is that the wiring of the meter is not reversed, but it may be that the load side has a load like a two-phase orange ruler AC welding machine, resulting in the dial sometimes reversed and reversed, which is a normal phenomenon and is generally not treated or used with a two-way metering energy meter.

Reason: It is usually said that if the inflow and outflow of the current coil are connected incorrectly, it will lead to reversal, and if CT is used, it is necessary to check whether the polarity of the secondary wiring is correct, otherwise it will also lead to the reversal of the watt-hour meter. This is the original side cherry tree of the reversal of the three-phase watt-hour meter.

Summary. 1. A three-phase four-wire electric energy meter is equivalent to three single-phase electric energy meters. 2. If a current transformer is reversed, it is equivalent to the phase of the energy meter will be "reversed", for the above single-phase mechanical energy meter, the dial indication will be "reversed" back.

3. The current electronic energy meter is the same as the principle, when one of the phase current transformers is reversed polarity, there will be two positive wiring of the correct wiring of the electric energy meter, and a wrong wiring of the electric energy meter is reversed, when the three-phase load is balanced, the total amount of electricity recorded by the electric energy meter is the amount of electricity after positive and negative offset, that is, one-third of the correct reading.

May I ask the electronic three-phase four-wire electric energy meter, if it is reversed, will it be reversed? What if one phase is reversed, is it the same as a mechanical case?

1. A three-phase four-wire electric energy meter is equivalent to three single-phase electric energy meters. 2. If a current transformer is reversed, it is equivalent to the phase of the energy meter will be "reversed", for the above single-phase mechanical energy meter, the dial indication will be "reversed" back. 3. The current electronic electric energy meter is the same as the principle, when one of the phases of the current transformer polarity is reversed, there will be two electric energy meters of correct wiring, and a wrong electric energy meter of the sun line is reversed, when the three-phase load is balanced, the total amount of electricity recorded by the electric energy meter is the amount of electricity after positive and negative offset, that is, it is one-third of the correct reading.

4. It is not the same as the mechanical situation.

Solution: The three-phase four-wire watt-hour meter is reversed, and one of the three phases or two or three phases is reversed, and the corresponding reversed phase can be replaced at the inlet and outlet lines of the watt-hour meter.

Another situation is that the wiring of the meter is not reversed, but it may be that the load side has a load like a two-phase AC welding machine, resulting in the dial sometimes reversed and reversed, which is a normal phenomenon, and generally does not handle or use a two-way metering watt-hour meter.

Reason: It is usually said that if the inflow and outflow of the current coil are connected incorrectly, it will lead to reversal, and if CT is used, it is necessary to check whether the polarity of the secondary wiring is correct, otherwise it will also lead to the reversal of the watt-hour meter. This is the reason why the three-phase watt-hour meter is reversed.

Swap all the wiring of S1 and S2 of the three current transformers.

Either switch the direction of the transformer where the power cord of the 3 transformers enters and exits.

The incoming and outgoing lines inside or outside the meter are reversed. If it is submergible, it can only verify the meter.

1. When the line is reversed, the meter will be reversed if the line is reversed.

2. After the transformer is connected to the meter;

3. Three-phase four-wire electronic active energy meterA three-phase four-wire electronic active energy meter, including an electric energy meter metering unit, a voltage sampling unit, a current sampling unit and a power supply.