FOUR FAMILIES, FOUR SETS OF PAPER
XIAOPAI manufactures across four families. Oil-immersed power transformers run from S9 to S22 at 35 kV. Dry-type units sit in the SC(B)9 to SC(B)13 range at the same voltage, and vacuum circuit breakers cover 12 to 40.5 kV. The fourth family is the switchgear that houses those breakers. Each one leaves the works with its own routine test record and its own conformity paperwork. Treating four of them as one credential is the first mistake a tender review makes, and it is a mistake that only shows up after the container has sailed. The standards split along the same lines. The IEC 60076 series covers transformers, the IEC 62271 series covers switchgear and controlgear. A declaration that cites the transformer series tells you nothing about the breaker file, and a reviewer who checks one and assumes the rest has done a quarter of the job.THE MODEL LIST IS THE FIRST PAGE TO READ
A certificate or a declaration of conformity carries a list of model designations. That list is the scope, and nothing on the cover changes it. If the quotation says ZW32-24 and the list stops at ZW32-12, the paperwork does not cover the order, however prominent the CE mark is on the brochure. Read the list first. Read the standards and their editions second. Read the date third. The designation itself is a small decode, and it is worth learning. In S13-M the S stands for three-phase, 13 marks the loss level in the series, and M means a sealed tank with corrugated walls instead of a conservator. ZN85 and ZW32 follow the same habit: Z for a vacuum device, N for indoor or W for outdoor, and the number giving the voltage class in kV. A supplier who cannot decode their own model string cannot tell you what the certificate covers either.THE OIL-IMMERSED FILE: S9 TO S22 AT 35 KV
On the oil side the published range runs S9, S10, S11, S13, S20 and S22 at 35 kV. The distribution end of the same product line appears on the 10 kV pages, where S13-M covers 30 kVA to 2500 kVA at 6.3 or 10.5 kV with Yyn0 and Dyn11 vector groups. A file that lists the 35 kV models does not automatically cover a 10 kV order, and the reverse is just as true. Voltage class sits inside the model designation, not in a footnote under the table. The oil file also carries a temperature-rise record and a pressure test on the tank. Neither exists in a dry-type file. Two transformer families, two test regimes, two sets of evidence behind the same word on the cover page.THE DRY-TYPE FILE DOES NOT COVER OIL
Dry-type units are cast in epoxy resin and tested on a different set of dielectric and thermal criteria from an oil-filled tank, which is why the two families are certified separately. The published range here is SC(B)9 through SC(B)13 at 35 kV. Buyers sometimes assume a transformer supplier's file covers transformers as a category. It does not. If a project moves from oil to dry because of a fire rating in the building code, the paperwork has to move with it. Dry-type and oil-filled units differ on more than the tank.THE BREAKER FILE: 12 TO 40.5 KV
Breakers are the family where the model designation carries the most information, and where buyers most often compare the wrong two documents. ZN85 sits at 40.5 kV. ZW32 appears at 12 kV and 24 kV. VSG and VF2 complete the range. A certificate that names the 12 kV build and an order for the 24 kV build are two different conversations, even when the same factory makes both. Field inspection starts by reading the rating plate against the order, and the plate follows the model. Physically the breaker is a vacuum interrupter inside a pole, driven by a mechanism, with the three poles on a common frame. What changes across 12, 24 and 40.5 kV is insulation distance and the size of that frame, not the principle of interruption. That is why one factory can build all three voltage classes and still hold three separate entries in the file.SWITCHGEAR IS AN ASSEMBLY FILE
Switchgear is where component papers stop being enough. The assembly has its own rating plate: rated voltage, rated current, short-time withstand current, protection degree. The breaker inside can be fully covered and the assembly still not be, because the assembly was type tested as a combination rather than as a list of parts. Ask for the assembly document, then ask which breaker designations it was tested with.THE LOSS PAGE INSIDE THE FILE
Every transformer file carries a loss table: rated capacity down the side, no-load loss and load loss across, with impedance and vector group alongside. That page is what a factory acceptance test actually measures, and it is the page a certificate reviewer tends to skip. If the declared no-load loss and the figure on the routine test sheet disagree, the file is not finished, however many stamps it carries. Impedance measurement is the other page worth reading before you accept a test sheet at face value. For a buyer the loss page has one practical use. It turns a vague claim about efficiency into two numbers per rating that can be measured on the test bed. When the sheet comes back, the question is not whether the unit passed. It is whether the measured no-load loss sits inside the tolerance the standard allows for that rating, and whether the figure was taken at the tap position you will run.THREE MATCHES BEFORE YOU ACCEPT THE FILE
Match the certificate model list against the quotation, line by line. Match the quotation against the nameplate drawing that will be produced for your units. Match the routine test serial numbers against the units actually being shipped. Three matches take ten minutes at a desk, and they remove most scope disputes before anything is loaded. For a power transmission and distribution equipment supplier with CE certification in China, those three matches are the whole review. A FAT checklist written for substations covers the same ground at the works.WHAT THE CERTIFICATE DOES NOT PROVE
Type testing proves a design. It does not prove every unit, and that is what routine tests are for. CE also says nothing about losses, nothing about temperature rise in your ambient, and nothing about how the equipment behaves on a weak grid. The sequence from type test to site acceptance is where those answers live. Paperwork review and technical review are two jobs, usually done by two people, and one does not replace the other. XIAOPAI ships the routine test sheet with every unit for exactly that reason.FIVE QUESTIONS THAT SORT SUPPLIERS
Which family is this file for. Which model designations does it list, exactly, including voltage class. Which standards and editions appear in the declaration. Who signs it, and for which legal entity. What changes if the rating moves one step up or down. Any power transmission and distribution equipment supplier with CE certification in China should answer those five from memory or from a lookup, without forwarding a PDF first. A supplier who can do that knows their own file, and that is a better signal than a folder of scans.WHAT XIAOPAI SUPPLIES
Wenzhou Xiaopai Electric Power Technology Co., Ltd. manufactures power transmission and distribution equipment in Wenzhou, across four families that each carry their own file. XIAOPAI builds oil-immersed transformers from S9 to S22 at 35 kV, dry-type units in the SC(B)9 to SC(B)13 range, and vacuum circuit breakers from 12 to 40.5 kV. The switchgear that houses those breakers comes off the same floor. Each family ships with its own document set in English, and XIAOPAI issues the model list with the quotation rather than after it. The published specification sits on the site, one page per family: oil-immersed transformers, dry-type transformers, vacuum circuit breakers and high-voltage switchgear.ONE LINE FOR THE RECORD:
A CE file covers the models it names, so the review is a matching exercise between certificate list, quotation and nameplate, one product family at a time.
A CE file covers the models it names, so the review is a matching exercise between certificate list, quotation and nameplate, one product family at a time.
