Vacuum circuit breaker
MV vacuum circuit breakers, 12-40.5 kV, 25-40 kA breaking capacity. Rated short-circuit breaking and mechanical endurance are confirmed against the type-test certificate.
InquireCircuit Breakers
The Circuit Breakers we reverse-engineer, verify, and negotiate on your behalf. Pick a model or send us the spec.
Molded-case breaker (MCCB)
MCCBs up to 1600 A for LV distribution and motor protection. Trip curves, breaking capacity Icu/Ics, and thermal rating are verified against declared manufacturer data.
InquireMiniature breaker (MCB)
MCBs for residential and final-branch protection, 6-125 A, B/C/D curves. Breaking capacity and curve class are checked against the nameplate rating.
InquireHow equivalence is judged on breakers
Breakers are the most frequently cross-branded component in a panel, and equivalence decisions first need to separate the two families: the IEC world (60947 series) and the ANSI world (C37 series). There is no simple swap between them — frame sizes, breaking capacity and the reference conditions behind protection curves are all defined differently.
The item checklist: matching rated current and frame size; ultimate and service breaking capacity (Icu/Ics) at or above the requirement; whether the drawout mechanisms compatibly bolt into the existing cubicles; matching the trip unit family (thermal-magnetic vs electronic) and its setting curves; and whether the named model on the type-test certificate is the one on your PO.
Bidders using a "same parameters, cheaper" pitch are common; real risk hides in the detail: channel goods assembled as genuine, an Icu value claimed on a higher frame class than the ordered unit, curve libraries written for a different redeployment. The free 48-hour screen gives a direction; the Spec Match tier books each parameter against a shortlist.
Breakers: the world's factory sits in one town
Breakers are the component most often cross-branded in a panel, and they are also the most geographically concentrated category in this list.
01
Density
From the first low-voltage electrical shop opened in Liushi, Yueqing in 1978, the area grew into the only national-level advanced manufacturing cluster in China led by a county. Low-voltage electrical products from it hold over 65% of the domestic market, and a single miniature-breaker line can complete some 3 million units a day.
02
Product breadth
The cluster spans 200-plus series, 6,000-plus categories and 25,000-plus models, with a local supply rate near 85%. Frames, trip units and drawout carriages do not need to be sourced from another province — but that also means two units sold under the same model number can carry entirely different grades of material.
03
So the verification lands here
The actual rating at which Icu and Ics were validated; the availability and licensing of the protection-curve library and its setting software; and channel authenticity — assembling a unit from channel goods when the authorised distributor is out of stock is not rare.
04
And across the two families
The IEC 60947 world and the ANSI C37 world are not a simple swap: frame sizes, breaking capacity and the reference conditions behind the curves are all defined differently. The free screen tells you which side of that line you are actually on.
Name the breaker and we will read it back to you
A model number, a nameplate photo or the frame and breaking capacity is enough. One verdict within 48 hours, one core reason, and — where it matters — the curve, channel and certificate scope questions you should be asking the supplier.
Brand equivalents in this category
Equipment sourcing FAQ
How do you tell a real factory from a trading office?
We cross-check the business-licence scope, social-insurance headcount, and customs filing. A "manufacturer" with two insured staff and no production-equipment records is almost always a trader reselling someone else's unit. We also look at whether the address is an industrial park or a serviced office.
Can you match a specific brand or model to the right manufacturer?
Yes. Send us the brand and model, or just a nameplate photo, and we reverse-engineer the key parameters: rated voltage, impedance, cooling class, protection grade. Then we shortlist Chinese manufacturers whose product line genuinely covers those parameters. This is the Spec Match tier.
Can you negotiate on my behalf?
Yes. The Procurement Execution and Remote Audit tiers include independent negotiation support, and On-Site Verification covers the physical checks; either way, we sit on your side of the table, not the factory's.
Do you take commissions from factories?
Never. We're paid only by you, on a flat fee. When we name an alternative supplier, we state in writing that we have no financial relationship with it. No referral fees, no kickbacks, no revenue share. Our only incentive is that your deal closes.