What are CLASS I, CLASS II, and LPS? What are the differences between CLASS I and CLASS II?

What are CLASS I, CLASS II, and LPS?  What are the differences between CLASS I and CLASS II?

CLASS I: This type of equipment provides protection against electric shock through basic insulation and also provides a protective grounding impedance connected to the building. In the event of a basic insulation failure, this grounding impedance will withstand a dangerous voltage to ground. In other words, CLASS I switching power supplies provide a pair of ground terminals.

CLASS II: This type of equipment not only relies on basic insulation for protection against electric shock but also requires additional double or reinforced insulation safety measures. It does not rely on grounding protection. In other words, CLASS II switching power supplies do not provide a pair of ground terminals.

LPS: Its main purpose is to ensure that when electronic circuits are powered by LPS, the current and energy in the circuit are below the specified standard values required by IEC 62368-1 Table Q.1, thus greatly reducing the risk of fire. Therefore, the spacing and fire resistance rating of components in this circuit are significantly reduced, and the casing material can be HB-rated plastic to save costs. The primary requirement is for Class 2 electronic circuits. Class 2 primarily aims to ensure that the current and energy supplied to these circuits are below the specified standards in UL 1310 Table 30.1, significantly reducing the risk of fire. Therefore, the spacing and fire resistance rating of components in these circuits can be significantly reduced, allowing for the use of HB-rated plastic casings to save costs. This is primarily based on UL Class 2 Power Units (UL 1310).