Here, we need to add that SELV has regulations on voltage values. The voltage specified here is the effective value of the voltage. Usually, the peak value of the voltage is higher than the effective value, and the voltage limit specified in clause 8.1.4 is the requirement for the peak value. We will explain its test requirements in detail in clause 8.1.4. Note 2 of first paragraph in Clause 3 give sentence “NOTE 2 When the terms “voltage” and “current” are used, they are r.m.s. values, unless otherwise specified.”
As shown in the figure below, the transformer has three plastic brackets placed vertically into the disc to separate the primary and secondary windings (the primary and secondary windings are wrapped with blue plastic tape on the outside), and the primary and secondary windings are physically isolated.
As shown in the figure below, the transformer has yellow tape wrapped around the primary and secondary windings in the middle. We need to pay special attention to the creepage distance of the black bracket between the two windings to see if it can meet the creepage distance requirements for reinforced insulation. If not, the transformer cannot be judged as a safety isolating transformer.
We will explain the structure of the safety isolating transformer in detail in the next post.
motor-operated appliance: appliance incorporating motors but without any heating elementNote 1 to entry: Magnetically driven appliances are considered to be motor-operated appliances. Household electrical appliances usually use heating elements or motors to complete their designed functions. The main functions are heating, such as heating food or air, and rotation or mechanical movement of products, such…
