High voltage

1.1 Safety precautions

Before carrying out electrical wiring, equipment operation, inspection and maintenance, you must read the contents of this manual in detail to ensure correct use. It is also necessary to be familiar with the situation of peripheral supporting equipment and relevant safety precautions.

About the wiring

◆ Wiring work must be carried out by professional technicians in accordance with relevant electrical safety operating standards.

◆ The inverter must be installed in place before wiring.

◆ Wiring shall be carried out in strict accordance with the engineering drawings provided by the company.

◆ Ensure good grounding of equipment and system.

◆ Inverter output terminals (U, V, W) are strictly prohibited to connect to AC power supply.

Relevant operational use

◆ Only after the transformer and power unit cabinet door is closed, can the transformer and power unit be powered on for operation. It is strictly prohibited to force the above cabinet door to be opened during operation;

◆ It is strictly prohibited to operate the switch with wet hands;

◆ It is strictly prohibited to touch the live part of the inverter when the power is switched on;

◆ Do not control the start and stop of the high voltage inverter by using the circuit breaker on and off the power grid.

1.2 Safe Operation

This series of products is suitable for 3-10kV power supply system, the equipment is directly connected to the high-voltage power grid, please do the following safety protection during operation:

1) The operator shall wear high-voltage resistant insulating shoes before entering the operation position of high-voltage equipment;

2) Insulation MATS shall be laid around the equipment;

3) High-pressure operation is strictly prohibited.

1.2.1 Inspection before the first power transmission, or before the power transmission after maintenance and overhaul

Check the project

◆ Confirm whether the high voltage input/output cable connection terminal screw is tightened or not;

◆ Confirm that the cables between the cabinets separated for transportation have been correctly and securely connected;

◆ Confirm that all control lines and signal lines are correctly and firmly connected;

◆ Ensure that the system grounding wires between all cabinets separated for transportation are reliably connected to the ground of the plant;

◆ Make sure that the series cables and neutral cable between units are properly and securely connected.

1.2.2 Routine check before power transmission

Check the project

◆ Remove all ground protection wires before power transmission.

◆ Check whether the filter screen needs to be replaced.

◆ Check whether the inverter fault information has been properly handled.

◆ Close and lock the cabinet door of the inverter.

1.2.3 Blackout operation

Operating the project

◆ Inform all relevant stations to prepare for power failure.

◆ Press the stop button of the high-voltage converter to stop the operation of the equipment.

◆ Disconnect the circuit breaker of the user inlet cabinet.

1.2.4 Maintenance operation

Repair items

◆ Necessary measures should be taken when maintaining the circuit: disconnect the circuit breaker, disconnect the relevant isolation switch, and hang the warning board at the same time to prevent others from sending power halfway.

◆ Confirm the shutdown state and the high voltage live indicator does not show.

◆ After high/low voltage power cut off, electrical inspection must be carried out before work; When conducting high-voltage electroscope, the electroscope with corresponding voltage level should be used. Insulating protective articles must be worn.

◆ After verifying that there is no electricity, ground the three-phase incoming line of construction equipment to ensure the safety of staff.

◆ Grounding wire should be installed at all possible places of the construction equipment to transmit electricity. For double-circuit power supply units, when repairing a bus brake, isolation switch and load switch, not only should the two bus brake be disconnected, but both ends of the construction brake should be grounded.

◆ When installing the ground wire, grounding wire should be earthed first, and grounding wire should be hanged after. When disassembling the ground wire, the order is opposite. Insulation protective equipment should be worn when disassembling and connecting the ground wire.

◆ The grounding wire should be hung in a place visible to the staff at any time, and the warning sign of "someone working" should be hung at the grounding wire.

1.2.5 Security rules and warnings

The design of high voltage inverter has fully considered the safety of user operation. However, due to the energy storage capacitor inside the frequency converter power unit, it may still have a high voltage after the power is disconnected, and some components have high heat, so it is strictly prohibited to touch. When working in or near the inverter site, please follow the following rules:

dangerous

◆ Prior to any maintenance or overhaul, correct operating procedures must be strictly observed;

◆ Maintenance and overhaul of the frequency converter can only be carried out after the frequency converter is confirmed to have been cut off and cooled;

◆ Equipment installation and electrical wiring must be in accordance with national and industrial standards.

◆ After turning off the input circuit breaker switch, there is still voltage in the cabinet. Please check and confirm that there is no voltage before operation;

◆ The instrument used shall meet the pressure resistance requirements, and keep the enclosure of the instrument well grounded;

◆ Be very careful when measuring the components in the cabinet. Do not let the watch rods collide with each other or touch other terminals.

◆ Only professional technicians can install, overhaul and maintain the frequency converter;

◆It is prohibited to replace or dismantle the cabinet top wind machine without turning off the control power.

Attention

◆ It is strictly prohibited to disconnect the control cabinet control power during high voltage power supply;

It is strictly prohibited to store flammable materials in, on or near the high voltage cabinet, including equipment drawings and manuals;

◆ For long distance transportation, please use a flat truck to transport the frequency converter, and ensure that the base of the frequency converter is horizontal; In case of rain and snow, please take adequate rain and snow prevention measures before transportation, such as using linoleum cloth wrapped inverter;

◆ When lifting the frequency converter, ensure that the crane, rope and crane have enough tonnage;

◆ When disposing of discarded components (such as capacitors), the appropriate regulations and requirements must be followed.

To prevent electrostatic

Some components in printed circuit boards and power units are sensitive to static electricity and must be removed before contacting or servicing these components, which must be accomplished by a professional technician. The elimination of static electricity should follow the following rules:

◆ Operators shall wear anti-static bracelets;

◆ Electrostatic sensitive devices must be stored in anti-static bags during transportation;

◆ When holding printed circuit board, hold the edge part;

◆ It is strictly prohibited to slide the PRINTED circuit board on any surface;

◆ When sending components back to the manufacturer for repair, anti-static devices must be used for safety packaging.