What should I pay attention to when designing the Integrated Wiring and grounding system?

Integrated Wiring Grounding SystemPay attention to the following issues during design:

1. When the Integrated Wiring System adopts shielding measures, the continuity of all shielding layers should be maintained and the relative positions between wires should be kept unchanged.

The FD or BD end of the shield layer shall be grounded, and the user terminal equipment shall be directly grounded according to the specific situation. The grounding at both ends shall be connected to the same grounding body as far as possible. When there are two grounding bodies in the grounding system, the Grounding Potential Difference should not be greater than 1Vr. m. S valid value ).

2. When a cable enters the building from the outside, it is vulnerable to lightning strikes, power touch, power induction potential, ground potential floating, and other external factors, a protective device must be used.

3. When the line is in any of the following dangerous environments, it should be protected against overvoltage and overcurrent:

1) dangerous effects caused by lightning strikes.

2) power supply lines with a working voltage greater than V touch the ground;

3) power failure caused by the increase of ground potential to over V;

4) The AC 50Hz induction voltage exceeds 250 V.

4. For the overvoltage protection of the Integrated Wiring System, the gas discharge tube protector should be used.

Because the Ceramic Housing of the gas discharge tube protector is sealed with two electrodes, there is a discharge gap between them, and there is a inert gas. When the potential difference between two electrodes exceeds v ac voltage or V lightning surge voltage, the gas discharge tube begins to have an arc, providing a conductive path between the conductor and the ground electrode.

5. The overcurrent protection of the Integrated Wiring System should be self-healing.

Due to the possibility of one voltage or another on the cable, if the connection device provides a low-resistance path to the ground, it is not enough to enable the overvoltage protector to operate, the current may damage the device or cause fire. For example, the 20 V power line may be insufficient to discharge the overvoltage protector, but may generate a large current into the device, causing damage. Therefore, the over-voltage protection must be used at the same time. The self-recovery overcurrent protector is required to facilitate maintenance.

The stability and reliability improvement of the Integrated Wiring and grounding system will be a long-term and arduous task for the majority of engineering and technical personnel. Because, with the continuous development of Intelligent Buildings, people will put forward more stringent requirements on their grounding systems.