China manufactures a very large share of the world's low voltage electrical equipment, and the range of quality inside that share is wider than in most markets. The difference between a good and a bad purchase is rarely the price; it is whether the specification was clear and whether anyone checked.
1. Standards are not interchangeable
Chinese equipment is commonly designed and tested to GB standards. GB/T 7251.3-2017 covers distribution boards and corresponds to IEC 61439-3; GB/T 7251.1 corresponds to IEC 61439-1. A supplier who says “IEC standard” without naming the part has not answered the question.
If your project requires IEC or another national standard, state it at enquiry stage. The answer may be that the design is the same and the documentation is different, but you need to know which.
2. Documentation is part of the product
Ask for the drawing set, the device list, the routine test record and the type test report before you compare prices. Equipment that arrives without documents is difficult to accept, difficult to insure and difficult to maintain.
3. Know who you are buying from
A trading company and a workshop sell differently. A trader can offer a wider range and better export handling; a workshop controls the assembly directly. Both models work, provided the party you are buying from is clear about which one they are and can answer technical questions without a relay.
4. Components are where substitutions happen
The enclosure and the busbar are visible; the breakers inside are not. Put the device list on the approved drawing, with brand and model, and check the packing list against it. If a device is unavailable, you want a question, not a surprise.
5. Inspection before packing
A routine test record is standard. A witnessed factory acceptance test is not, and costs time, but on a large board it is usually worth it. Photographs at agreed milestones are a practical middle ground.
6. Packing and transport
Switchgear travels badly when it travels cheaply. Specify export packing: plywood or timber crates, ISPM 15 treatment where timber is used, moisture protection, lifting marks and a packing list inside the crate. A board that arrives with a bent frame costs more than the packing saved.
7. Terms that matter more than the price
- Incoterm. FOB, CIF and DAP put different risks and costs on each side. Agree the term explicitly, with the named port or place.
- Payment. Deposit and balance against documents is normal. The balance trigger should be a document you can verify.
- Warranty. Twelve months from delivery is common. Check what it covers and who pays the freight on a replacement part.
- Spare parts. Devices, gaskets, indication lamps and a spare door key. Ask for them on the first order, when they cost almost nothing.
- Changes after approval. Agree in writing what happens to price and schedule if the drawing changes.
8. Lead time is a schedule, not a number
Ask what the lead time is measured from: order, deposit, or approved drawing. Most delays attributed to production are actually delays in drawing approval, and the two are treated very differently when a project is running late.
9. Language and response
Technical correspondence in English, with drawings in a format your engineer can open. A supplier who answers in two lines but answers correctly is more useful than one who writes three paragraphs of reassurance.
10. Start with one board
If you are trying a new supplier, start with a single assembly before committing the whole project. It answers every question above at low cost (quality, documentation, packing, communication) and gives you a reference for the next order.