Can each set of low-voltage power supply divide multiple loads?
The power distribution cabinet has two sets of wires, the power distribution cabinet has two yellowish-brown things, and the power distribution cabinet has two cables. Related technical articles The power distribution cabinet has two sets of 380V low-voltage power supplies.
As long as the three-phase current of each branch is basically balanced, you can branch out as many paths as you like.
Three-phase balanced circuit. The so-called three-phase balanced circuit refers to a circuit in which the three-phase load voltage and current are basically the same. In this circuit, the three-phase active power is equal to three times the single-phase active power.
Why can several shunts be divided only when the three-phase balance is ensured?
This is a three-phase four-wire power supply line. In this line, it is inevitable to connect single-phase electrical equipment, such as single-phase lighting or single-phase inductive load (motor). As long as there are single-phase equipment connected, it is difficult to ensure the balance of the three-phase current. When the balance is unbalanced, which phase has more single-phase equipment connected, the current of which phase will be large. In the case of the same diameter of the three-phase wires, the wire with a large current will definitely burn out first.
At the same time, the unbalanced current will produce different voltage drops in the three-phase power supply, resulting in three-phase unbalanced grid voltage. Therefore, when distributing the load, it is necessary to calculate the current borne by each phase, and distribute it on the three phases as evenly as possible, so that the three-phase current is roughly balanced. road.
When the three-phase current imbalance exceeds 25%, for a three-phase motor, a reverse rotating magnetic field can be generated on the stator of the motor, and the motor will run under the action of two rotating magnetic fields, positive and negative. . Since the forward rotating magnetic field is much stronger than the reverse rotating magnetic field, the motor still rotates in the forward direction. However, there is a reverse rotating magnetic field in the stator, so the electromagnetic torque of the motor is reduced, which will cause additional heat generation in the motor winding.
Finally to sum up
Two sets of 380V power supplies enter the switchgear, not necessarily the same number of shunts for both sets of power supplies, and the shunt load of one set of power supplies can be more than the shunt load of the other set, but the precondition is that the three-phase load must be balanced as much as possible equal.
