1. There are many electronic equipment in clean room with single-phase loads and unbalanced currents. Moreover, there are fluorescent lamps, transistors, data processing and other non-linear loads in the environment, and high-order harmonic currents exist in the distribution lines, causing a large current to flow through the neutral line. The TN-S or TN-C-S grounding system has a dedicated non-energized protective connection wire (PE), so it is safe.
2. In clean room, the power load level of process equipment should be determined by its requirements for power supply reliability. At the same time, it is closely related to the electrical loads required for the normal operation of the purification air conditioning system, such as supply fans, return air fans, exhaust fans, etc. Reliable power supply to these electrical equipment is a prerequisite for ensuring production. In determining power supply reliability, the following factors should be considered:
(1) Clean rooms are the product of the development of modern science and technology. With the rapid development of science and technology, new technologies, new processes, and new products are constantly emerging, and the precision of products is increasing day by day, which puts forward higher and higher requirements for dust-free. At present, clean rooms have been widely used in important sectors such as electronics, biopharmaceuticals, aerospace, and precision instrument manufacturing.
(2) The air cleanliness of clean rooms has a great impact on the quality of products with purification requirements. Therefore, it is necessary to maintain the normal operation of the purification air conditioning system. It is understood that the qualification rate of products produced under specified air cleanliness can be increased by about 10% to 30%. Once there is a power outage, indoor air will quickly become polluted, affecting product quality.
(3) The clean room is a relatively closed body. Due to power outage, the air supply is interrupted, the fresh air in the room cannot be replenished, and harmful gases cannot be discharged, which is detrimental to the health of the staff. Electrical equipment that has special requirements for power supply in clean room should be equipped with an uninterruptible power supply (UPS).
Electrical equipment with special requirements for power supply refers to those that cannot meet the requirements even if the backup power supply automatic input method or diesel generator emergency self-starting method still cannot meet the requirements; general voltage stabilizing and frequency stabilizing equipment cannot meet the requirements; computer real-time control system and communication network monitoring system etc.
Electrical lighting is also important in clean room design. From the perspective of the nature of the process, clean rooms are generally engaged in precision manufacturing, which requires high-intensity and high-quality lighting. In order to obtain good and stable lighting conditions, in addition to solving a series of problems such as lighting form, light source, and illumination, the most important thing is to ensure the reliability and stability of the power supply.
Post time: Apr-12-2024