There are two technical standards for PSE.
When acquiring PSE for a device or device subject to PSE, it does not matter which technical standard PSE is acquired.
Two types of PSE technical standards
Among the 116 items of PSE’s Specified Electrical Appliances and Materials, there are items that are subject to “DC power supply“, but general switching power supplies are not PSE’s “DC power supply”.
This is because switching power supplies are not used by themselves and are not applicable to PSEs that target final products because they are premised on being incorporated into equipment.
In order for a switching power supply to be a PSE target product, there are some conditions in terms of shape so that it can be used by itself.
PSE was changed from the ministerial ordinance item ◯ standard to the attached table ◯ in 2014, but the technical standard did not change and only the construction changed. PSE has traditionally had two technical standards.
・ Appended Table 12 (Technical standards compliant with international standards and standards of the former Ministerial Ordinance, Paragraph 2)
* There is no original technical standard of Appended Table 12, and the international technical standard of IEC becomes the technical standard of ” Appended Table 12″ as it is.
The technical standards for switching power supplies are shown in ” Appended Table 8″ as “DC power supply”, and in ” Appended Table 12″, IEC international standards are specified as “power supply”.
There is no difference in PSE regardless of whether you obtain PSE in ” Appended Table 8″ or ” Appended Table 12″.
It is not that which technical standard is more difficult or easier, but the items of the technical standard are different. The 12th international standard in Appended Table 12 has strict EMC (electromagnetic compatibility) and harmonic current regulations, and Appended Table 8 in the domestic standard has stricter insulation distance and creepage distance.
Which PSE should be obtained？
Since the design standards and test methods of switching power supply manufacturers comply with the international standard IEC60950-1, it is not difficult to obtain a PSE in ” Appended Table 12″.
On the other hand, in order to obtain PSE in ” Appended Table 8″, the edge surface, space, and insulation distance between the transformer and the circuit board are stricter than IEC60950-1 in ” Appended Table 12″, so the power supply itself becomes large.
Then, I think that you should get PSE in “Appended Table 12”, but there is one problem.
When a manufacturer acquires a PSE, for example, if a switching power supply that has acquired the PSE in ” Appended Table 8″ is purchased and the device side also applies for PSE in the same ” Appended Table 8″, as long as the switching power supply is used within the standard. Does not require re-evaluation of the power supply.
On the other hand, if the device side obtains a PSE that is different from the switching power supply, the conformity test for the power supply will not be simplified. For example, when the device is trying to acquire PSE in Appended Table 8 and the built-in switching power supply has acquired PSE in Appended Table 12. In this case, it is necessary to evaluate the entire device in Appended Table 8, that is, to re-evaluate the power supply section in Appended Table 8.
Details are described in “Handling of DC power supplies for lamp appliances” by the Ministry of Economy, Trade and Industry.
A common problem is that switching power supplies are incompatible in Appended Table 8. This happens because the technical standards of PSE are different between (1) domestic standards and (2) international standards. Specifically, it is the transformer of the switching power supply and the edge surface, space, and insulation distance of the circuit board. In this case, the design of the switching power supply itself must be changed, which is not realistic. When applying for a PSE for a device, it is wise to first look for a switching power supply that has the same PSE as the PSE you are trying to obtain.