A power transmission and distribution equipment supplier with CE certification China ships more than transformers. One item on the packing list is a metal-enclosed switchgear panel, the cabinet that takes power from a busbar and hands it to a feeder through a vacuum circuit breaker.
Buyers often assume the panel inherits the breaker's paperwork. It does not. They are two objects, tested to two standards, and each needs its own evidence before the assembly is legal to place on the market.
WHAT THE PANEL ACTUALLY IS
The panel is a steel enclosure at 12 to 35 kV holding a withdrawable breaker, three busbars, current and voltage transformers, a cable compartment, an earthing switch and a protection relay. Its job is to carry normal current, hold fault current for a stated time and trip the breaker when the relay asks.
Panels rarely travel alone. They leave the factory as a line-up of three or four cubicles, sometimes bolted into a packaged unit with a transformer, which is the same logic behind modular substations. Every cubicle in that line-up carries the same obligation.
TWO OBJECTS, TWO TYPE TESTS
The breaker is built at 12, 24 and 40.5 kV and tested to IEC 62271-100, with IEC 62271-1 covering the general requirements. A type test proves the design family can interrupt a stated short-circuit current at a stated voltage. Routine tests then run on every unit before it leaves.
The panel is tested to IEC 62271-200, the standard for metal-enclosed switchgear from 1 kV to 52 kV. That test looks at different things: the enclosure, the busbar supports, the earthing switch, the degree of protection, and the internal arc behaviour if the maker claims it.
None of that can be borrowed. A breaker that interrupts 25 kA says nothing about whether the enclosure survives an arc at 25 kA, or whether the busbar supports hold. Factory assembly moves more of this into the works, as it has for gas-insulated substations, but the two tests stay separate.
FIVE INTERLOCKS THAT DO NOT EXIST ON A LOOSE BREAKER
The safety of a panel lives in its interlocks, and interlocks are a property of the assembly. A breaker bought loose has none of them.
In a withdrawable cubicle the breaker cannot be racked in or out unless it is open. The earthing switch cannot be closed while the circuit is live. The cable compartment cannot be opened while the breaker is in service. The breaker cannot be closed with the earth switch closed.
Those rules are mechanical, not software. They are designed into the shutter, the racking mechanism and the key logic of the cubicle. This is also why switching is planned around them. An arc, when one happens, is treated as a design case rather than an accident, as the work on arc flash protection sets out.
ONE RATING STRING, THREE PLACES
Every panel has a rating string: voltage class, rated current, short-circuit withstand and its duration, and the earthing switch rating. That same string has to appear in three places, and the three have to agree.
It appears on the breaker nameplate, on the panel rating plate and in the test report or declaration behind the panel. A 25 kA rating quoted at 12 kV is not a 25 kA rating at 24 kV, and a supplier who quotes one number for the whole range has not finished the calculation.
Two mismatches show up more than others. A panel rated 25 kA shipped with a 20 kA breaker, and a 40.5 kV cubicle fitted with a 24 kV breaker because the line-up was extended later. Both pass a visual check and fail a fault.
Where the feeder ends at a transformer, the protection settings have to be built on that transformer's impedance, and the oil-immersed range runs from S9 to S22 at up to 35 kV.
WHAT THE DECLARATION MUST NAME
The declaration is one page, and it is a legal statement rather than a test result. It names the manufacturer and an address, the directives applied, the standards applied and the person who signs.
Two details decide whether it is worth the paper. The first is the standard edition. A declaration that cites a superseded edition of a harmonised standard has lost its presumption of conformity, and the withdrawal date is published in the Official Journal. The second is the product identification. A declaration written for a family has to name the family in a way that matches the rating plate on the unit in front of you.
Test reports sit behind the declaration. They are evidence, not the statement itself, and a report from a laboratory without accreditation for that test carries less weight than a report with it.
WHAT A CHINESE SUPPLIER CAN AND CANNOT DO
A supplier in China can hold the design file, commission the type tests, issue the declaration and hand over routine test records. For low-voltage and medium-voltage equipment the declaration is made by the manufacturer, and no third-party certificate is required for it.
What the same supplier cannot do is act as the importer. When the buyer brings the panel into the EU, the importer's name and address go on the unit, and the importer carries duties the factory cannot carry for it. A supplier who offers to "handle the CE" beyond the declaration is either describing an EU representative arrangement or overstating what a piece of paper can do.
A power transmission and distribution equipment supplier with CE certification China is therefore worth checking family by family. A file for transformers does not cover a panel, and a file for one panel family does not cover a different one.
WHERE CE STOPS ON SITE
The panel arrives compliant and can be installed non-compliantly. Cable termination, earthing continuity, CT ratio, relay settings, interlock proving tests and the commissioning record all sit outside the factory gate.
This is where most of the risk moves. Commissioning and acceptance testing is the step that converts a delivered panel into a protected circuit. Protection settings also need revisiting as the feeder mix changes, which is the argument behind adaptive protection.
WHAT TO ASK BEFORE THE ORDER
Six questions sort most of it out. Which standard was the panel type-tested to, and by which laboratory? Which edition appears on the declaration? What is the rating string at each voltage class offered, written out in full? Are the interlocks included and tested as an assembly? Who signs the declaration, and who is the importer? What is excluded from the supply and left to site?
Ask for the panel file and the breaker file separately, then lay the rating plates beside them. If the three strings match and the interlocks were proved in the works, the rest of the conversation is about schedule rather than substance.
WHO MAKES IT, WHO SHIPS IT
Wenzhou Xiaopai Electric Power Technology Co., Ltd. manufactures vacuum circuit breakers from 12 to 40.5 kV and the switchgear cabinets built around them in Wenzhou, Zhejiang, and exports both. The vacuum circuit breaker range covers indoor, withdrawable and pole-mounted versions, and the cabinets are supplied with the transformer feeders they protect, oil-immersed or dry-type.
CE is a file per object, not a logo per shipment. The panel that arrives with two files, matching ratings and proved interlocks is the one that will pass a grid inspection without a second trip to the factory.
