How to correctly install the grounding wire of diesel generator set

Grounding measures for diesel generator sets during installation are a necessary prerequisite to ensure the safety of operators and electricity. Professional technical operators will emphasize the importance of grounding wire installation, and correct installation according to the instructions is one of the safety protection measures for the generator set.

Grounding measures are generally divided into three types: protective grounding, working grounding and protective grounding. Hechai Power shares the following instructions with you:

1. Protective grounding:

Protective grounding is mainly used to provide certain safety protection when the neutral point is not grounded.

Protective grounding can prevent the risk of electric shock when the motor housing becomes live due to improper operation or maintenance. Therefore, the protective grounding of the generator set can effectively alleviate accident damage.

2. Working grounding:

(1) Reduce the insulation level of electrical equipment to ground. In a system with an ungrounded neutral point, when one phase is grounded, the ground voltage of the other two phases will rise to the line voltage. For systems with a grounded neutral point, when one phase is grounded, the voltage to ground of the other two phases is only close to the phase voltage, so the insulation level of electrical equipment and transmission lines can be reduced.

(2) Reduce the electric shock voltage. For a system with an ungrounded neutral point, when one phase is grounded and a human body touches one of the other two phases, the electric shock voltage is more than 1.7 times the phase voltage; while for a system with a grounded neutral point, the electric shock voltage drops to nearly equal to the phase voltage. .

(3) Quickly cut off the faulty equipment. For systems where the neutral point is not grounded, when one phase is grounded, the capacitance and insulation resistance between the conductors and the ground can form a current path. The grounding current is very small, which is not enough to cause the protective device to operate and cut off the power supply, which cannot ensure personal safety. .

3. Protection connection to zero:

For power generation units working in high-power or harsh environments, protective connections need to be used for protection.

When the leakage of the chassis exceeds the protective grounding load, it will easily cause serious harm to the surrounding environment and the human body. Especially in humid or high-temperature environments, it may affect major electrical accidents; therefore, for high-power or long-term harsh environments, Generator sets in the environment must have protective zero connection facilities so that when a leakage accident occurs in the generator, the fuse can be blown in time to avoid the expansion of the accident.

Precautions for correct installation of ground wire:

1. The grounding wire needs to be installed according to the requirements of the customer and the location.

2. The connection point of the ground wire is generally at the end of the chassis of the generator set. When installing the ground wire, it must be connected to the correct ground wire location.

3. Customers need to ensure that the equipment wiring is always effectively maintained, and the maintenance of the wiring system should be performed strictly in accordance with the instructions.

4. If the installation is complex, the grounding midpoint should be selected to ensure the correct operation of the generator set or to maintain the equipment. For example, if a grounding fault is found, the grounding circulating current should be minimized.

5. When the generator set is used as the only power source, the neutral wire needs to be directly connected to the factory ground wire.

6. When configuring the protection connection to zero, confirm whether the transformer has leakage protection.

7. The ground wire configuration of foreign and domestic generator sets may be different, so you need to ask the generator set manufacturer in detail when configuring the protective zero connection.

During the use of the diesel generator set, the grounding wire can promptly detect unsafe conditions that occur due to various reasons.