EN IEC 62271-200 High Voltage Switchgear and Controlgear - Part 200: AC Metal-Enclosed Switchgear and Controlgear for Rated Voltages Above 1 KV and Up to and Including 52 KV

The standard “EN IEC 62271-200 High-voltage switchgear and controlgear - Part 200: AC metal-enclosed switchgear and controlgear for nominal voltages above 1 kV and up to and including 52 kV”, which has its origin in a European standard and was subsequently published by the International Electrotechnical Commission (IEC), is applicable to prefabricated metal-enclosed switchgear and controlgear assemblies designed for:

• Alternative current
• Nominal voltages above 1 Kv and up to and including 52 Kv
• Service frequencies up to and including 60 Hz
• Indoor and outdoor installation

The assembly may include air-insulated or liquid-filled chambers.

The latest update of this standard constitutes a technical revision and includes the following significant technical changes:

• In service, special definitions are added for normal operating condition and normal use.
• Internal arc testing on pole-mounted switchgear is removed from the scope of this standard as it is now covered by the specific standard IEC 62271 214.
• A more precise definition of the ground loop is given by the addition of ratings and testing requirements.
• The number of mechanical tests on the locking devices has been reduced for type testing. A more precise definition of the forces to be applied during type testing is given.
• The resistance measurement in the main circuit is only necessary before the continuous current tests (as a reference for routine tests) and is no longer necessary after this continuous current test. The reason for this deletion is that this measured resistance does not mean anything. Since the temperature rise test has just finished, a new temperature rise test will not provide any new information.
• A more precise definition of the LSC (loss of service continuity) category is provided by attaching an explanatory flow chart (Appendix D).
• Samples not covered by the IAC test were displaced.
• The term assembly is defined and used in this standard as a synonym for metal-enclosed switchgear and controlgear.
• Metallic is replaced by metal where applicable.
• A new rule has been introduced for Criterion 4 during IAC tests where hot gases cause ignition against glowing particles.
• A more precise description of internal arc tests for switchgear with protrusions is given in Annex A.

This standard now defines all medium voltage distribution panels and cubicles as metal. In other words, open type cubicles are no longer within the scope of this standard. This standard classifies medium voltage cubicles based on installation experience and requirements as follows:

• According to the type of partition material: If the energized parts (busbar compartment and cable connection compartment) and the accessible compartment (compartments where the circuit breaker and voltage transformer are located) are open, there are two types of cubicle classification according to the type of partition material in between:
  • Metallic partition: It refers to the partitioning done with metallic shutters.
  • Non-metallic partition: It refers to the isolated section larger than 12,5 mm2 that creates discontinuity in the partition.
• According to loss of service continuity (LSC): Within the standard, service continuity is classified into four main groups:
  • LSC1 class: Cubicles with one or more functional units having accessible high voltage sections such that at least one other functional unit cannot remain energized when any of the accessible high voltage sections is opened. In LSC1 class cubicles, the main busbar must be de-energized to reach the circuit breaker.
  • LSC2 class: The breaker and cable are in the same compartment. This compartment can be accessed when the busbar is energized. Because this compartment can be isolated and grounded by means of the separator and grounding separator located in the busbar section. In these cells, the main busbar does not need to be de-energized to reach the breaker. Therefore, service continuity can be ensured when the accessible section is opened. If the cell has another accessible section other than the cable section, other classifications should be applied.
  • LSC2A class: In these cells, after the disconnector is opened and the earthing switch is closed, both the circuit breaker section and the cable section can be accessed safely while the main busbar is energized. In order to access the circuit breaker section, the cable energy must be cut off and grounded. The difference from the LSC2 class cell is that the cable and the breaker are in separate compartments.
  • LSC2B class: The cable compartment of the cubicle and the busbar compartment of other cells connected to the same busbar may be under voltage. It is the type of cubicle that allows energy to be present on the main busbar and cable connection point when the breaker is desired to be reached. These types of cubicle can be fixed type or withdrawable type. The structure for cubicles with fixed type breaker is quite similar to the cubicle structure in LSC2A class. In addition, there is a second separator and grounding separator in the cable connection compartment.
• According to access type and internal arc resistance: According to standard access types, medium voltage switchgears are divided into two classes as A and B types.
  • In type A access, authorized personnel can intervene in the cell.
  • In type B, access is unrestricted. Any staff or member of the public can access.

When defining access types, it is also necessary to specify which direction is suitable for access according to the internal arc resistance. If internal arc protection is required from the front and both sides of the cubicle, FL codes are used, if internal arc protection is required from all surfaces, FLR codes are used (F: from the front, L: from the sides, R: from the back).

Our organization, which has been trying to support businesses from every sector with its testing, measurement, analysis and evaluation studies carried out in a wide range for years, has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. In this context, testing services are also provided to businesses in accordance with the standard “EN IEC 62271-200 High voltage switchgear and controlgear - Part 200: AC metal enclosed switchgear and controlgear for nominal voltages above 1 kV and up to and including 52 kV”.