Capacitor installation skills
1 When installing capacitors, the wiring of each capacitor should preferably be connected to the bus with a separate flexible wire. Do not use hard bus connections to prevent assembly stress from damaging the capacitor casing and breaking the seal and causing oil leakage.
2 Any poor contact in the capacitor circuit may cause high-frequency oscillating arcs, which will increase the working electric field strength of the capacitor and generate heat and cause early damage. Therefore, it is necessary to maintain good contact between the electrical circuit and the grounding part during installation.
3 When the capacitors of lower voltage level are connected in series and run in the higher voltage level network, measures such as installing insulators equivalent to the operating voltage level should be adopted to ensure reliable insulation between the housing of each unit and the ground.
4 After the capacitor is connected in a star shape, it is used for a higher rated voltage and the neutral point is not grounded. The shell of the capacitor should be insulated from the ground.
5 Before the capacitor is installed, the capacitance should be allocated once to balance the phases, and the deviation should not exceed 5% of the total capacity. When a relay protection device is installed, it should also meet the requirement that the balance current error does not exceed the relay protection operating current during operation.
6 The wiring of individual compensation capacitors should be done: For induction motors that are started directly or via a varistor, the power factor-increasing capacitors can be directly connected to the outlet terminals of the motor, and no switchgear or fuse should be installed between the two ; For induction motors started with star-delta starters, it is best to use three single-phase capacitors, each capacitor is directly connected in parallel to the two terminals of each phase winding, so that the connection of the capacitor is always consistent with the connection of the winding .
7 For the grouping compensation low-voltage capacitor, it should be connected to the outside of the low-voltage grouping bus power switch to prevent self-excitation when the grouping bus switch is disconnected.
8 The low-voltage capacitor bank for centralized compensation should be specially equipped with switches and installed on the outside of the main line switch, not on the low-voltage bus.Capacitor installation skills