Do Mobile Generator Sets Need to be Grounded

1. Structure and function of mobile generator sets

The trailer frame of the mobile generator set is welded with groove beams, with reasonable node selection, high strength, and good rigidity; At the same time, it is equipped with a leaf spring suspension structure. The trailer adopts a height adjustable pin type traction frame, suitable for towing vehicles of various heights; Adopting a circular steel pipe welded straight axle, the structure is compact and reliable. The four corners of the frame are equipped with mechanical support devices, equipped with inertial service braking, parking braking, and emergency braking to ensure the safety of the unit under various conditions. There is a support wheel in front of the frame, which not only bears the vertical load of the unit but also has a guiding function. The entire vehicle is equipped with turn and brake indicator lights, as well as standard tail light plugs. The mobile diesel generator set series has a variety of structures and functions: manual, three wheel, four wheel, automobile power station, trailer power station, mobile low-noise power station, mobile container power station, electric engineering vehicle, etc. The Dingbo mobile generator is designed and produced by referring to the structure of multiple external mobile power stations, and has good operational and safety performance. There are the following configuration options:

(1). Traction: Adopting movable hooks, 180 ° turntable, flexible steering, and convenient operation.

(2). Braking: Equipped with reliable air brake interface and manual brake system, ensuring safety during driving.

(3). Support: To ensure the stability of the power truck during operation, it is equipped with a 4R mechanical or hydraulic support device.

(4). Doors and windows: There are ventilation windows in the front, opposite doors in the rear, and doors on both sides for operators to enter and exit.

(5). Car body size: The size of the car body depends on the specifications, and the operator can walk around for easy operation and maintenance.

(6). Appearance: The paint is made of polymer polyurethane paint, and the color can be customized by the user. The exhaust pipe adopts upper or lower exhaust to ensure aesthetics. The text and decoration on the exterior of the car body can be made according to user requirements.

(7). Fire protection: The vehicle can be equipped with two fire extinguishers.

2. Do mobile generator sets need to be grounded?

Mobile generator sets require grounding. From the perspective of safety production, regardless of the size of the generator, whether it is a movable or fixed generator, if its output voltage is 380V, the center point should be grounded, and the generator casing should also be grounded. If the voltage is 3-10KV, the center point is not grounded, but the generator casing should be grounded. For a 380V generator, if the center point of the generator is not grounded when one of the live wires is grounded, the voltage of the other two live wires to ground will increase from 220V to 380V, increasing the risk of personal electric shock. Therefore, grounding is necessary. The grounding of the generator casing is to prevent damage to the live wire edge inside the generator and contact with the iron core. If the casing is not grounded, it is not only difficult to determine the fault and cannot trip in a timely manner, but also there will be voltage in the generator casing, posing a risk of electric shock to those in contact.

Mobile generator sets are suitable for construction sites, large-scale breeding sites, outdoor mining, media outdoor interviews, and so on. Therefore, grounding is more necessary and safety precautions should be taken.

Mobile generator sets can extend their service life by following the correct operating methods. Dingbo Power recommends customers to refer to the mobile generator set operation manual for implementation. What is the reason for grounding during use.

3. Working grounding refers to the grounding of the neutral point, with the purpose of:

(1) Reduce the electric shock voltage. In a system where the neutral point of a generator set is not grounded, when the phase is grounded and the human body touches the other two phases, the electric shock voltage is more than 1.7 times the phase voltage; For systems with neutral grounding, the electric shock voltage drops to close to or equal to the phase voltage.

(2) Quickly cut off faulty equipment. For systems with ungrounded neutral points, due to the presence of capacitance and edge resistance between the conductor and the ground during phase grounding, a current path can be formed. The grounding current is small enough to cause the protective device to operate and cut off the power supply, which cannot ensure personal safety; For the neutral point earthing system, when the grounding current is large after the phase is grounded, the protection device will act quickly to disconnect the fault point.

(3) Reduce the edge level of electrical equipment to ground. In a system where the neutral point is not grounded, when the phase is grounded, the ground voltage of the other two phases will increase to the line voltage; For systems with neutral grounding, when the phase is grounded, the ground voltage of the other two phases is only close to the phase voltage, which can reduce the edge level of electrical equipment and transmission lines.

4. Protective grounding

The protective grounding of generator sets is commonly used in low-voltage systems where the neutral point is not grounded. Its function is to: when the edge structure of a certain winding of the motor has been damaged and the casing is electrified, if it is not grounded and the human body touches the casing, it is equivalent to a single-phase electric shock, and there may be a risk of electric shock. If protective grounding is used, when the human body touches the shell, due to the parallel connection between the human body's resistance and the grounding resistance, the human body's resistance is much greater than the grounding resistance, and the current passing through the human body is very small, so there is no risk of electric shock.

5. Protective neutral connection

Protective neutral connection is often used in low-voltage systems with neutral grounding. Its function is to use protective neutral connection to form a single-phase short circuit when the edge structure of a motor winding is damaged and connected to the casing. Current can quickly fuse the fuse in this phase, and the casing is no longer live. Even if the human body touches the shell before the fuse is blown, the human body resistance is much greater than the line resistance, and the current passing through the human body is very small, so there is no risk of electric shock.

The installation of mobile generator sets also requires skills. Below, Kangwo will teach you the installation skills of mobile generator sets hand in hand.

Mobile generators are mainly installed on movable platforms such as cars, trailers, or trailers, and their installation layout requirements are as follows.

1. The platform should be selected in a solid, flat, and dry place. In general, no fixed measures need to be taken between the platform and the ground, but the chassis of the unit should be ensured to be stable.

2. Check the firmness and correctness of the connections at each connection point, especially the foundation bolts, couplings, and the wiring between the generator and excitation system.

3. Bury the grounding device of the equipment according to the specified requirements and firmly connect the grounding wire. When the diesel generator set is working in the open air, necessary measures shall be taken to prevent rain, moisture, snow, sun and sand, so as to avoid electric shock accidents and maintain the normal working performance of mobile generators.