Table of Contents

Search for “China UL DC isolator” and you will find hundreds of listings with a UL logo in the product photo. Very few come with a UL file number. We spent October 2026 checking the ten Chinese suppliers most often quoted to export buyers, and ranked them by how much public evidence backs their UL claims, not by how loudly they make them.

Short answer: the Chinese suppliers with the strongest public evidence of UL-listed PV disconnects are ZJBENY (BENY), NOARK, CHINT, HIITIO and ONCCY. ZJBENY was the first Chinese maker with a UL 508i DC switch (2016). NOARK and HIITIO publish UL file numbers for 1,500 VDC disconnects. CHINT publishes UL 489B certificates for its ASD16 DC disconnector. Suntree, People Electric and Delixi are linked to UL claims we could not confirm, and FEEO and GEYA sell solid IEC-certified isolators but showed no UL listing when we checked.

Last updated: October 2026. Method: for each supplier we looked for a UL file number on the maker’s own site or datasheet, a downloadable UL certificate, or a product page naming the UL standard and model. “Not found” means we did not find it publicly; it may exist, and suppliers are welcome to send us the file number.

What we could verify, supplier by supplier

SupplierProductUL standardPublic evidence we foundStatus
ZJBENY (BENY)BYSS rotary switches; BH-250 / BH-400UL 508i; UL 98B2017 announcement of first Chinese UL 508i listing; product pages with UL ratingsStrong
NOARKASD16, ASD25 DC disconnectsUL 489B; UL 489 Supplement SCFile numbers E529657 and E529658 in catalogueStrong
CHINTASD16 DC disconnectorUL 489BUL 489B certificate downloadable on CHINT GlobalStrong
HIITIOHCG4-1200; HCG4-4000UL 98B; UL 489BFile E544157 (HCG4-1200) and E541391 (HCG4-4000) on datasheetsStrong
ONCCYEDS7 rotary switchesUL 508iUL 508i rating table on product pages; no file number shownGood
SuntreeSDS rotary switchesUL 508i (claimed)Datasheet claims UL testing; certificate page shows CB, TÜV, SAA onlyVerify
People ElectricGHX6-55P rotary switchClaimed by third partiesNo UL listing found on maker siteVerify
DelixiCDW9 (as cited by third parties)UL 98 (claimed)No UL listing found on maker siteVerify
FEEOFDIS, FPIS isolatorsNone foundIEC 60947-3; TÜV, CB, SAA, CEIEC only
GEYAGDSC100R rotary isolatorNone foundIEC 60947-3 and AS 60947.3IEC only

The ten suppliers, ranked by evidence

1. ZJBENY (BENY)

Zhejiang Benyi, based in Yueqing, earned the first UL 508i listing for a Chinese DC switch with its BYS series in July 2016 and announced it in October 2017. Its current BYSS rotary switches are listed to UL 508i at 1,000 V for 16 to 30 A (higher currents at lower voltages) and at 1,500 V for 13 A, in 2 to 9 poles. For combiner boxes, BENY markets the BH-250 and BH-400 disconnects as UL 98B listed at 1,500 V. It is the safest Chinese starting point for both small inverter switches and large combiner disconnects.

2. NOARK Electric

NOARK, a Suzhou-based brand with a North American operation, publishes the clearest UL paperwork of any Chinese name here. Its ASD16 (600 to 1,600 A) and ASD25 (800 to 2,500 A) DC disconnects are rated 1,500 VDC, four poles in series, and listed to UL 489B (file E529657) and UL 489 Supplement SC for batteries and storage (file E529658), with CSA certification under the same files. Smaller UL 489B DC disconnects cover 125 to 400 A. One caution: NOARK’s RDS1 rotary switch is UL 98 at 600 Vac only. It is not a PV DC disconnect.

3. CHINT

CHINT’s ASD16 DC disconnector, 600 to 1,600 A at 1,500 VDC with 75 kA short-time withstand, complies with UL 489B and UL 489 Supplement SC, and CHINT Global lets anyone download the UL 489B certificate. The same model name and ratings appear in NOARK’s catalogue. CHINT’s small PV isolators are a different story: the Ex9IP modular isolator (up to 1,000 VDC) and Ex9IR50 rotary switch (50 A at 1,100 VDC, 26 A at 1,500 VDC) are documented to IEC 60947-3, not UL. Specify the exact model when you ask CHINT for “UL”.

4. HIITIO

HIITIO focuses on high-current DC switching for storage and utility PV. Its HCG4-1200 disconnect (600 to 1,200 A, 1,500 VDC, 2 poles) states UL 98B compliance and UL file E544157 on the datasheet. The larger HCG4-4000 (1,600 to 4,000 A) is listed to UL 489B under file E541391. It is a good fit for battery containers and large recombiners rather than rooftop isolators.

5. ONCCY

Shanghai-based ONCCY sells the EDS7 rotary switch range with a UL 508i rating table on its product pages: 30 A at 600 and 800 VDC, and 13, 20, 25 or 30 A at 1,000 VDC, in 2 to 10 poles. Marketing headlines mention 1,600 V and 63 A, but the UL table we saw stops at 1,000 VDC, so use the UL table, not the headline, for North American designs. Ask ONCCY for its UL file number before ordering.

6. Suntree

Suntree is a large Yueqing maker of DC components, and its SDS rotary switches are widely used in inverters and combiner boxes. Its datasheet says the series passed UL 508i testing (written as “UL 5081”) and lists UL among its certifications. The certificate page on its isolator website, however, shows CB, TÜV and SAA documents only. Treat the UL claim as unconfirmed until you see a file number that matches the model.

7. People Electric

People Electrical Appliance Group makes the GHX6-55P rotary isolation switch, rated 55 A at 1,500 VDC (DC-PV1) and 45 A at 1,100 VDC (DC-PV2), launched at SNEC 2021. A widely shared Chinese “top 10 UL isolator” list attributes a UL 508 listing to a People Electric DC switch series. We could not find that listing on People Electric’s own site or a file number to check. Ask for it directly.

8. Delixi

Delixi is one of China’s largest low-voltage brands. Third-party lists describe a Delixi CDW9 DC isolation switch as UL 98 certified at 1,000 VDC. Two issues: we found no such listing on Delixi’s site, and UL 98 is the general enclosed-switch standard, not the PV-specific UL 98B. For PV work in the US, ask Delixi which UL standard and file cover the exact part.

9. FEEO

FEEO (Yueqing) makes a broad PV component range, including FDIS rotary isolators up to 80 A and 1,500 V and FPIS high-current isolators up to 315 A at 1,000 or 1,500 V. These are documented to IEC 60947-3 with TÜV, CB, SAA and CE. We found no UL listing. FEEO is a reasonable IEC-market supplier, not a UL source.

10. GEYA

GEYA’s GDSC100R rotary isolator is rated 32 A at up to 1,200 VDC, four poles, compliant with IEC 60947-3 and AS 60947.3 (DC-PV1 and DC-PV2). Like FEEO, it suits European, Australian and Asian projects. We found no UL listing, so it should not appear on a US drawing. TOMZN’s 1,200 V and 1,500 V rotary isolators fall into the same category.

Why some “UL disconnects” are listed to UL 489B

UL 489B is the standard for molded-case circuit breakers and switches used in PV systems. A molded-case switch, essentially a breaker without trip units, can be listed under it and used as a disconnect. That is why NOARK, CHINT and HIITIO quote UL 489B for some of their largest DC disconnects. For rotary isolators up to about 85 A, expect UL 508i. For enclosed and dead-front disconnects in combiners, expect UL 98B. If a supplier offers a PV disconnect listed only to UL 98 (no B) or UL 508 (no i), ask why.

Red flags on a Chinese “UL” quotation

  • A UL logo on the product photo, but no file number in the quote or datasheet.
  • A UL file that belongs to a different company, with no multiple-listing arrangement.
  • UL ratings identical to IEC ratings. UL voltage ratings are often lower, as ONCCY’s own tables show.
  • A standard that does not match the application, such as UL 98 or UL 508 for a PV DC disconnect.
  • A test report offered in place of a listing. Testing to a standard is not the same as being listed.

ShineTong supplies DC isolator switches and combiner boxes and states the certification of each model in writing. We do not quote UL ratings we cannot document. For globally branded UL options, see top 10 global UL isolation switch manufacturers. Breaker-side protection is covered in China MCB manufacturers and solid-state circuit breaker manufacturers.

Frequently asked questions

Which Chinese company was first to get UL 508i for a DC switch?

ZJBENY (Zhejiang Benyi). Its BYS series was listed to UL 508i in July 2016, and the company announced it in October 2017 as the first Chinese UL 508i DC switch.

How can I check a Chinese supplier’s UL certificate?

Ask for the UL file number (starting with E) and exact model code, then search the file in UL Product iQ. Confirm the company name, model family and voltage and current ratings match your order.

Is UL 489B acceptable for a PV disconnect switch?

Yes, for molded-case switches used as disconnects in PV systems. NOARK, CHINT and HIITIO list some large 1,500 VDC DC disconnects to UL 489B. Smaller rotary isolators are normally UL 508i, and enclosed combiner disconnects UL 98B.

Are IEC-certified Chinese DC isolators safe to use?

For IEC markets such as Europe, Australia and much of Asia, a properly IEC 60947-3 certified isolator from a reputable maker is appropriate. It is not acceptable for US installations under the NEC, which require listed equipment.

Why are UL voltage ratings lower than IEC ratings on the same switch?

UL and IEC test methods differ. ONCCY’s EDS7, for example, is marketed at up to 1,500 V insulation, but its UL 508i table stops at 1,000 VDC. Always design to the UL rating for North America.

Sources