Grid and nuclear-adjacent electronics for Finland are specified for decades, and Walsin’s paperwork is silent on the use. We read all 28 datasheets, 451 pages: nuclear, substation, grid, relay and marine appear in none. Radiation appears in 1, the MLCC application guide, as an environment where the capacitor should not be used.
Venatech Limited, an authorised Walsin distributor in Hong Kong, wrote this for a design engineer or buyer at a Finnish maker of grid, power-plant or marine automation electronics: protection and control boards, auxiliary supplies, drive and measurement modules. It uses the 28 datasheets we hold from Walsin Technology (Walsin), its MLCC export of 24,026 rows (23,601 distinct part numbers) and our stock snapshot dated 23 September 2026. We name no Finnish utility, plant or manufacturer, and we say nothing about anyone’s supply or approval. Every part number is real, every count is ours, and each news statement carries its source, date and the day we read it.
What is Finland building, and why does a component buyer care?
A grid and a nuclear fleet that are both on long timelines, which means long-life parts decisions made now. Caverion announced on 10 April 2026 a contract of about 18 million euros to build a new 400 kV substation for Fingrid at Åbacka in Ostrobothnia and expand two others, at Kajaani and Muhos, with construction starting in 2027 and completion expected in 2028. We read the release on 22 October 2026.
ANS Nuclear Newswire reported on 11 September 2026 that Google and Fortum signed a multidecade nuclear power purchase agreement supplying power from the Loviisa plant through 2050, with deliveries to Google’s Finnish data centre infrastructure starting in 2028. The same report says Finland’s 2023 decision extended Loviisa’s operating licence to the end of 2050. World Nuclear News, dated 16 February 2023, reports the government’s extension of both Loviisa units to the end of 2050. The Fingrid construction page says main-grid investment will rise to 5.2 billion euros under its 2026 to 2035 development plan, on a page dated 26 October 2022.
Our view, labelled as ours: a control board designed for a substation that opens in 2028 or a plant licensed to 2050 will be repaired and rebuilt for a long time. That makes two things matter: what the capacitor’s paperwork says about the place it sits, and whether the part is still orderable a decade on. We cannot promise the second, and we counted the first.
What do Walsin’s 28 datasheets say about grid, nuclear and marine use?
Nothing about any of them. We searched the extracted text of all 28 Walsin datasheets, 451 pages, for 12 words from this brief: nuclear, substation, grid, relay, power plant, marine, vessel, offshore, ship, sea, salt and cold. Every one returns zero files. The words that do appear are high voltage, in 10 files, and radiation, ozone and ultraviolet, each in 1.
| Term searched | Files containing it (of 28) | What a Finnish buyer can conclude | Match / mismatch (needs the sheet to name the use) |
|---|---|---|---|
| nuclear, substation, grid, relay, power plant | 0 | No sheet names a plant or a grid use | Mismatch: the sheets are silent on the use |
| marine, vessel, offshore, ship, sea, salt | 0 | No sheet names a marine or salt-spray condition | Mismatch: the sheets are silent on the use |
| cold, arctic | 0 | No sheet uses either word; the temperature appears only as a range | Mismatch: read the range, below |
| high voltage | 10 | Ten sheets use the phrase, mostly as a series name or a test condition | Match on the word, not on a grid rating |
| radiation, ozone, ultraviolet | 1 each | The same file carries all three words: the MLCC application guide | Match on the words; the sentence is a prohibition |
| -55 to +125 °C | 23 | The common printed range for the standard dielectrics | Match for a -40 °C winter, with margin |
We have not seen this counted anywhere: the word radiation appears once in 451 pages, and the sentence it sits in says not to use the capacitor there. A nuclear-adjacent programme needs a radiation-tolerance statement; what we hold is a limit. We hold no radiation test, no dose figure and no qualification report. Our post on MLCC shelf life, storage and handling covers the guide’s other environment warnings.
Where does the radiation sentence live, and what does it forbid?
In the application guide only, on page 2 of 12, as one of six environments. Section 5-1-3 of the MLCC application guide tells the user to confirm the operating environment and not to use the equipment where it is splashed with water or oil, exposed to direct sunlight, exposed to ozone, ultraviolet rays or radiation, exposed to toxic gas, subject to vibration or shock beyond the limits, or in moisture-condensing conditions. That is six environments, and we read the page.
The guide is 1 of 26 MLCC files we hold. We checked the other 25, which include the full catalogue and all 24 series approval sheets: none repeats the ozone, ultraviolet or radiation wording. A designer who opens only the sheet for the part number in front of them never sees the list. Nor does either of the 2 resistor sheets.
| Environment in section 5-1-3 | Likely to occur in a hall with high-voltage gear? | Match / mismatch (against what the series sheets repeat) |
|---|---|---|
| Spattered with water or oil | Possible near cooling or hydraulics | Mismatch: not repeated in the series sheets |
| Direct sunlight | Outdoor kiosks | Mismatch: not repeated |
| Ozone, ultraviolet rays, radiation | Our reading: ozone from corona near high-voltage gear; radiation inside a plant | Mismatch: stated in 1 of 26 MLCC files |
| Toxic gas, such as hydrogen sulfide or ammonia | Pulp, fertiliser or sewage sites | Match: the sulfur and ammonia warning is in 26 of 26 MLCC files |
| Vibration or shock beyond the limits | Compressors, switchgear operation | Match: every sheet prints a vibration test |
| Condensing moisture | Cold start-up of an unheated enclosure | Match: damp-heat and humidity tests are printed |
Which high-voltage parts would a substation designer start from?
From the Middle and High Voltage series for the 230 V class, and the sheet is silent on the plant. We counted the Middle and High Voltage series in Walsin’s export: 4,095 rows, 3,871 distinct part numbers, from 200 V to 4 kV, of which 637 rows are rated 630 V. All five parts below are real, and none of their sheets carries the radiation or ozone wording.
| Walsin part | Sheet | Case | Rated voltage | Operating temperature printed | On our shelf, 23 Sep 2026 | Match / mismatch (auxiliary-supply filter, -40 °C winter, plant or hall position) |
|---|---|---|---|---|---|---|
1812B104K631 |
Middle and High Voltage | 1812 | 630 V, 100 nF X7R | -55 to +125 °C | Yes | Match on voltage margin and range; mismatch: no ozone or radiation statement |
0805B104K500 |
General Purpose | 0805 | 50 V, 100 nF X7R | -55 to +125 °C | Yes | Match on range; mismatch on voltage for mains-side use |
HT21G331K500 |
High Temperature HT | 0805 | 50 V, 330 pF X8G | -55 to +150 °C | Yes | Match on range, with 25 °C more; mismatch: small capacitance, no radiation statement |
MT21B104K500 |
Automotive MT | 0805 | 50 V, 100 nF X7R | -55 to +150 °C and -55 to +125 °C in two columns | No | Mismatch: automotive wording, and not on the shelf |
S242B101K502 |
Safety S2 | 1808 | 5000 V impulse, 100 pF X7R | -55 to +125 °C | No | Mismatch: the export field is impulse voltage, working voltage is in the datasheet only |
The S2 row repeats a known defect in the export: its Rated Voltage field is the impulse voltage on all 173 rows, and the working voltage lives only in the datasheet. Our post on soft termination MLCC covers the series that tolerate board flex when a unit is serviced.
What do we hold in stock for grid and plant electronics?
Part of the high-voltage ladder, and no plant-rated part. We joined the 3,871 distinct Middle and High Voltage part numbers to our stock list as at 23 September 2026, 1,125 part numbers: 149 are on the shelf, from 200 V up to 3 kV. Two High Temperature part numbers are held, both 0805 X8G at 50 V.
So a 630 V class capacitor can often be a shelf item and a nuclear-qualified one cannot, because we hold no such part and no radiation document. We quote no lead time for anything off the shelf. Part-number counts are what we quote, never piece counts. The ready stock page shows what is held now, and the MLCC range lists the families.
How can Venatech help a Finnish grid or plant electronics maker?
By crossing the capacitor you already use, stating each difference, and telling you what the sheet does not say. Venatech Limited is an authorised Walsin distributor in Hong Kong. Walsin is our only authorised line, and the other lines we supply are Stackpole and Viking.
- Cross-reference. Paste your incumbent number into the free cross-reference tool, which decodes 18 manufacturers’ part numbers across 800,000+ crossable parts, and read each Walsin candidate with match and mismatch stated field by field.
- BOM check. Upload a protection-board or auxiliary-supply bill of materials to /bom/ and have each line checked against the same engine.
- Ready stock. The ready stock list is a Hong Kong snapshot dated 23 September 2026, never live-synced.
- Service. Hong Kong-based, small lots, cross-referencing help, and a quote requested through the site. Our address is Unit 207, 2/F, Sun Ling Plaza, 30 On Kui Street, Fanling, N.T., Hong Kong, telephone (852) 2628 4777.
A worked example from our own export: a 100 nF, 630 V, X7R capacitor on an auxiliary-supply input maps to 1812B104K631, which is on the shelf, with the datasheet sent on request and lot and date-code traceability. It is a match on voltage and temperature range and a mismatch on any plant-environment statement. We hold neither ISO 9001 nor any nuclear quality certification, and we make no nuclear, grid or marine claim for any part. Confirm against both datasheets and qualify in your own circuit.
The short version
Finland has a new 400 kV substation due in 2028 and a nuclear plant licensed to 2050, and Walsin’s 28 datasheets never name a substation, a plant or a ship. Radiation appears once in 451 pages, as a place not to use the capacitor, and 149 of 3,871 high-voltage part numbers are on our shelf.
Send us the capacitor from one protection or auxiliary-supply board and we will return the Walsin parts with the differences stated. If your plant position counts as a radiation environment, which document, not ours, says the part may sit there?
Sources
Fetched 22 October 2026. The news statements above are taken from these pages; the part data comes from our own Walsin exports, datasheets and stock list.
- Caverion, “Caverion to build a new 400 kV substation for Fingrid in Ostrobothnia and expand substations in Kajaani and Muhos”, 10 April 2026: https://www.caverion.com/newsroom/releases/2026/caverion-to-build-a-new-400-kv-substation-for-fingrid-in-ostrobothnia-and-expand-substations-in-kajaani-and-muhos–contract-value-eur-18-million/
- ANS Nuclear Newswire, “In a boost to Finland’s Loviisa plant, Google and Fortum ink nuclear PPA”, 11 September 2026: https://www.ans.org/news/2026-09-11/article-8381/in-a-boost-to-finlands-loviisa-plant-google-and-fortum-ink-nuclear-ppa/
- World Nuclear News, “Fortum granted licence extension for Loviisa”, 16 February 2023: https://world-nuclear-news.org/articles/fortum-granted-licence-extension-for-loviisa
- Fingrid, “Grid construction”, page dated 26 October 2022: https://www.fingrid.fi/en/grid/construction/
Frequently asked questions
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Do Walsin datasheets mention nuclear, substation or grid use?
No. We searched the text of all 28 datasheets we hold, 451 pages, for nuclear, substation, grid, relay, power plant, marine, vessel, offshore, ship, sea, salt and cold. Every term returned zero files. High voltage appears in 10 files.
Do Walsin capacitors have a radiation rating?
Not in the documents we hold. The word radiation appears once in 451 pages, in section 5-1-3 of the MLCC application guide, which lists radiation among environments where the equipment should not be used. We hold no radiation test or dose figure.
Where can I find the environments Walsin says not to use an MLCC in?
In the MLCC application guide, page 2 of 12, section 5-1-3, which lists six environments. We checked the other 25 MLCC files, including the 24 series sheets, and none repeats the ozone, ultraviolet or radiation wording.
Which Walsin capacitor suits a 630 V auxiliary supply input?
1812B104K631 is a 100 nF, 630 V, X7R part in the Middle and High Voltage series, printed at -55 to +125 degrees Celsius, and it is on our shelf as at 23 September 2026. Its sheet says nothing about ozone or radiation. Qualify it in your own circuit.
Do you hold nuclear or plant qualification for these parts?
No. We hold no document that names a nuclear use, no radiation report and no ISO 9001 certificate. We make no nuclear, grid or marine claim. We offer the datasheet and lot and date-code traceability. Qualification stays with you.
How much of the high-voltage range do you hold in Hong Kong?
As at 23 September 2026 we hold 149 of 3,871 distinct Middle and High Voltage part numbers, from 200 V to 3 kV. The ready stock page shows what is held now. Anything else is a factory order, and we quote no lead time.