What is a ground wire?

Ground wire, also known as lightning conductor, refers to the conductor used to lead current into the earth; When the electrical equipment leaks electricity, the current enters the ground through the ground wire, especially for high-power electrical appliances. Its function is to quickly lead the current to the ground through the grounding wire when your electrical equipment leaks electricity or is induced to be electrified, so that the equipment shell is no longer electrified, ensuring the safety of personnel and equipment.

Laser and laser equipment all need strong power to ensure stable operation. Because of the access of strong electricity, the grounding wire is a very important link in the use process. The laser ground wire can not only prevent electric leakage, but also prevent interference; If the grounding wire is not connected or not properly connected, not only the workers are vulnerable to injury when the machine leaks electricity, but also the laser circuit board is damaged.

Requirements for plant layout

1. Use galvanized round steel with a diameter of 12 or 5 * 50 galvanized angle iron to drive into the ground, with a depth of more than 1.5M and a grounding resistance of less than 4 Ω. If it fails to meet the requirements, it is better to drive more grounding piles, which are connected with galvanized flat iron in the middle;

2. Use copper wire (more than 16 square meters) to connect with the grounding wire of the equipment. The grounding wire of the machine tool, signal control cabinet, voltage stabilizer and laser can be connected on the wiring block and close to the grounding pile.

Correct wiring method

1. Preparation tools: multimeter, wrench, hexagon socket;

2. Connect the PE line of the laser with the ground wire of the voltage regulator, and use a multimeter to measure the resistance between the laser housing and the ground wire of the voltage regulator. If it is less than 1 ohm, the wiring is qualified; At the same time, connect the PE line of the machine tool and the machine tool control cabinet with the ground wire of the voltage regulator. Use a multimeter to measure the resistance between the machine tool and the machine tool control cabinet shell and the ground wire of the voltage regulator. If it is less than 1 ohm, the wiring is qualified.

3. Check whether the ground wire connection between the voltage regulator and the general distribution cabinet is connected. Use a multimeter to test the resistance between the voltage regulator ground wire and the general distribution cabinet ground wire. If it is within 4 ohms, it is normal;

4. Install the protection adapter plate. Connect the external control line of the laser and the machine tool control cabinet through the protection adapter plate. The two PE lines should be installed on the terminals of the adapter plate. After installation, measure the resistance of the PE terminal of the protection adapter plate and the PE terminal of the machine tool control cabinet when they are connected. If it is less than 1 ohm, the installation is qualified;

5. Check whether the installation of ground wire is qualified

【1】 The impedance of the laser housing to the ground wire should be less than 4 Ω when measured with a multimeter. (The ground wire of the laser exceeding the standard is not well connected)

【2】 The impedance between the laser and the machine tool housing shall be less than 1 ohm when measured with a multimeter. (The ground wire of the machine tool exceeding the standard is not well connected)

【3】 Unplug the external control line of the laser, power on the machine tool control cabinet, when the external control line is not connected, and when the control signal of the controller system (machine tool) is continuously output, the voltage of the control signal to the ground (EN+, EN -, PWM -, less than 25v DA+, and DA -, less than 11v), and there is no obvious spike in the oscilloscope measurement. (The ground wire of the control cabinet exceeding the standard is not well connected)

6. The troubleshooting test is completed and there is no abnormality, and the ground wire wiring is completed.

Unqualified wiring

NO.1

【1】 The PE line of the laser power supply line is not connected to the ground terminal of the voltage regulator;

【2】 The PE line of the machine tool power supply line is not connected to the ground wire terminal of the voltage regulator;

【3】 The PE line at the input end of the voltage regulator is not connected to the ground terminal of the circuit breaker or power distribution cabinet due to leakage;

【4】 The PE wire of the external control harness of the laser is not connected to the ground terminal of the fuse adapter board or the machine tool control cabinet due to leakage;

【5】 The PE wire of the machine tool control cabinet is not connected and is not installed on the ground terminal of the control cabinet.

NO.2

【1】 There is no gap between the ground wire not led to the ground pile laser, machine tool, machine tool control cabinet and the ground wire of the voltage stabilizer;

【2】 There is no gap between the ground wire of the voltage regulator and the ground wire of the input circuit breaker;

【3】 There is no gap between the ground wire of the circuit breaker at the input end of the voltage regulator and the ground wire of the general distribution cabinet.