A. Main reasons
1. Internal power generation equipment connected to the grid
There may be power generation equipment (such as solar power generation, wind power generation, etc.) inside the user. When the power generation of these equipment exceeds the power consumption of the user at a certain moment, the excess power will be fed back to the system through the power grid, causing the energy meter to record reverse active power.
2. Dual or multiple power users
For users with dual or multiple power supplies, there may be power over-conduction when running in parallel. When the power flow direction between the power supplies changes and part of the power is transmitted to the power grid, the energy meter will also record it as reverse active power.
3. Equipment inertia during system power outage
When there are large motor-type equipment inside the user, at the moment of system power outage, these equipment cannot stop immediately due to inertia, but may become "generators" to continue running. At this time, the generated power may be transmitted to the power source through the energy meter, resulting in the recording of reverse active power.
4. Wiring error
The wiring error of the three-phase multi function energy meter is a common cause of reverse active power recording. Wiring error may cause the current direction to be inconsistent with the voltage direction, thus forming reverse active power. This type of problem may be caused by factors such as incorrect wiring by electricians, old lines, loose wiring, etc.
5. Damaged meter
Aging and burning of meter components may also cause the problem of reverse active power in three-phase energy meters. Damage to the circuit inside the meter or failure of components may cause the meter to misread or misrecord the power.
6. Unstable power supply voltage
When the power supply voltage is unstable, the circuit inside the energy meter may be impacted or damaged, resulting in reverse active power. In this case, the measurement accuracy of the energy meter will be affected.
B. Solution
1. Check the wiring
First, check whether the wiring of the energy meter is correctly connected, especially the connection of the three-phase energy meter requires special attention. If the wiring is found to be incorrect, it should be changed and tested in time.
2. Replace the meter
If the energy meter components are severely aged or burned, it is recommended to replace the new energy meter in time. This process requires professional technicians.
3. Check the power supply voltage
If the three-phase energy meter has a reverse active power problem, it is recommended to check whether the power supply voltage is stable. If the power supply voltage is unstable, it is necessary to repair or replace the equipment in time.
4. Reactive power setting
In some cases, the reverse active power problem of the three-phase energy meter may be due to the presence of three-phase reactive power at the power supply end. At this time, the energy meter needs to be reactively set, and this process also requires professional technicians.
5. Strengthen maintenance and management
Regular maintenance and management of the energy meter, timely detection and resolution of problems can ensure accurate measurement and stable operation of the energy meter.