Low Voltage Distribution Cabinets: What We Build and What We Do Not
A distribution cabinet is a structural product, not an electrical one. The busbar, the breakers and the protection settings are yours. What we build is the enclosure that carries them: the frame, the doors, the mounting panel, the busbar supports, the gland plates and the finish — to a gauge that will not sag and a tolerance that will let the devices fit.
Fulei Metal builds low voltage distribution cabinets from customer drawings in mild steel, stainless 304/316 and aluminium, in a 2,500 m² plant in Ningbo, China, since 2016.
Distribution cabinet vs control cabinet
| Distribution cabinet | Control cabinet | |
|---|---|---|
| What it holds | Breakers, busbar, fuse switches, metering | PLC, drives, relays, terminals, HMI |
| Typical construction | Compartmentalised, heavier gauge, floor-standing | Lighter, wall or floor, device-dense |
| What decides the design | Busbar loading, segregation, arc-flash requirements | Device layout, heat, wiring access |
| Typical gauge | 1.5–3 mm frame, 2 mm+ doors | 1.2–2 mm |
| Typical IP rating | IP54 indoor, IP65 outdoor | IP54–IP66 |
What we build
| Item | Notes |
|---|---|
| Cabinet frame and body | Bolted or welded construction; we build both, and will say which suits your volume |
| Doors, including twin-door | With hinges, latches, locks and gaskets to the specified IP rating |
| Mounting panels and device plates | Thicker gauge, with stiffeners where the device load demands it |
| Busbar supports and insulators | Positioned to your drawing; we do not supply or install the busbar |
| Gland plates and cable-entry assemblies | Built into the wall with a flange and sealed joint, not patched on |
| Surface finish | Powder coating on an audited partner line; brushing and mirror polishing in-house |
| Pre-installed hardware | DIN rail, locks, hinges, labels, fans, filters — to your specification |
What we do not do
- Busbar fabrication and installation — copper or aluminium bar work sits with you or your panel builder
- Electrical wiring, device mounting, commissioning — we install the hardware you specify; we do not wire the cabinet
- Type testing and certification — type tests to IEC 61439 are run on the complete assembly by you or the certification body. What we provide is the enclosure built to your drawing, with dimensional records
- Short-circuit withstand verification — that is a property of the complete assembly, not of the metalwork alone
Being explicit about this boundary is deliberate. A cabinet that has been built well but never type-tested will still fail an inspection, and the metalwork is not where that failure originates. If your project needs the complete certified assembly, we are a component supplier in it, not the assembler.
Construction: bolted or welded
| Bolted | Welded | |
|---|---|---|
| Best for | Volume production, field assembly, flat-pack shipping | High IP rating, structural stiffness, one-off and low volume |
| Sealing | Gasket at every joint; more leak paths | Continuous welds; fewer joints to seal |
| Modification | Can be dismantled and re-drilled | Fixed once built |
| Lead time | Faster on repeat orders | Slower, but better for a first article |
Gauge, and why stiffness beats strength
| Part | Typical gauge | Why |
|---|---|---|
| Frame | 1.5–3 mm | Carries the door and the mounting panel; sag here misaligns everything |
| Door | 2 mm and up | A thin door bows, opens the seal and lets the latch miss |
| Mounting panel | 2–3 mm | Breaker and terminal mass; flexing pops fixings loose |
| Back and sides | 1.5–2 mm | Enclosure, not structure — unless it carries the panel |
Thickness we run: 0.5–18 mm mild steel, 0.5–15 mm stainless, 0.5–10 mm aluminium. Laser tolerance is held to ±0.05 mm on simple profiles.
What to put on the drawing
- Compartment layout — which devices go where, and the segregation between them
- Busbar positions and support points, with the insulator type
- Door arrangement — single, twin, or with an intermediate pillar
- IP rating and gasket specification, and whether the seal is replaceable
- Gland plate positions, sizes and entry direction — top, bottom or rear
- Earth bar position and whether it is masked before coating
- Coating masking list — threads, mating faces, earth points
- Lifting points if the cabinet is heavy enough to need them
Related reading
- Electrical enclosures and cabinets: the full selection guide
- Wall-mount electrical enclosures
- Enclosure thermal management
- IP66 enclosures: what the rating really means
Frequently asked questions
Can you build to IEC 61439?
We can build the enclosure to your drawing, and we will tell you what we can hold dimensionally. We do not perform type testing and do not issue IEC 61439 verification — that applies to the complete assembled assembly and is arranged by you or the certification body.
Do you do the busbar?
No. We build the supports and insulators to your drawing; the bar work and its installation sit with you or your panel builder.
Bolted or welded for an outdoor cabinet?
Welded, usually. Fewer joints means fewer leak paths, and the frame is stiffer. Bolted wins on volume and on flat-pack shipping cost, and is fine at IP54 indoors. Tell us the volume and the rating and we will say which we would build.
What is the largest cabinet you can build?
Our press brakes have a 3,000 mm bed and our lasers handle the sheet sizes involved, so the constraint is handling and shipping rather than fabrication. Cabinets up to roughly 2,000 mm tall and 800 mm deep are routine. Beyond that, we would discuss shipping and whether a bolted, flat-packed design makes more sense.
What lead times apply?
Simple samples 3–7 days. Complex first articles 15–20 days. Production batches 25–35 days, quoted after drawing review. Freight is quoted separately to your port.
Do you hold ISO 9001 certification?
Our quality system is documented to ISO 9001. We do not hold a third-party ISO 9001 certificate and do not claim one. Third-party audit evidence is available under NDA: TÜV Rheinland MIC-ASI243729 and Bureau Veritas MIC-ASR263630.
Send the drawing and the device list
Send the drawing with the device layout and the busbar positions. Those two decide the compartment structure, the gauge and the door arrangement — and they are what we need to tell you honestly whether the cabinet can be built the way it has been drawn.