Lighting distribution boxes
- Circuits: 6–36 circuits in modular layout, mixed single-phase (1P/1P+N) and three-phase (3P)
- Main switch: disconnect switch or miniature circuit breaker ≤63 A, with isolation indication
- Optional control: photocell, astronomical time control, timer — common for street lighting
- Enclosure: powder-coated cold-rolled steel, indoor IP30 / outdoor rainproof IP65 (rain hood + bottom entry)
- Components: Chint / Schneider / ABB miniature circuit breakers; brand may be specified or customer-supplied and sent to our plant
Specifications
The table below covers 80% of factory distribution room cases. Anything outside it we can still build — those are engineered items, quoted separately, with an indicative price the same day.
| Enclosure type | Indoor surface / flush mounting (embedding frame); outdoor rainproof version (rain hood + door gasket) |
|---|---|
| Standard dimensions (W×H×D) | 300×400×160 to 600×800×200 mm, sized by circuit count, custom build available |
| Enclosure construction | 1.2–1.5 mm cold-rolled steel, bent and welded, electrostatic powder coated |
| IP rating | Indoor IP30 / IP40; outdoor IP54 / IP65 |
| Door and lock | Full-length hinged door, latch or padlock; outdoor version with sealing gasket |
| Cable entry | Indoor knockouts; outdoor version with bottom cable gland entry, rainproof against splash |
| Rated voltage | AC 220/380V, 50 Hz |
|---|---|
| main breaker | Disconnect switch / 2P–3P miniature circuit breaker, ≤63 A |
| outgoing feeders | 6–36 circuits, single-phase 1P / 1P+N, three-phase 3P, modular |
| Miniature circuit breaker | C characteristic (standard for lighting) / D characteristic (for gas discharge lamp ballast inrush) |
| Ground fault protection | Main or branch leakage module (30 mA / 100 mA selectable) |
| Neutral and ground bars | Separate N neutral bar and PE ground bar, sized per circuit |
| Component brands | Chint / Schneider / ABB / Siemens, customer-supplied and shipped to factory accepted |
| Workshop lighting type | Three-phase incoming feed split into three-phase lighting circuits, zoned by bay / column spacing |
|---|---|
| Plant roadway lighting type | Outdoor enclosure + astronomical time control + multi-circuit zoning; half-night lighting scheme optional |
| Commercial floor type | Floor lighting and emergency lighting circuits on separate rows (emergency circuits confirmed per project requirements) |
| Manual-only economy type | No control module, manual operation, lowest cost |
| Photocell + time control type | Photocell (on at dusk) + time control (off at set time) combined, standard roadway lighting practice |
| Assembly standard | GB/T 7251.1 / IEC 61439-1 (low-voltage assemblies) and GB 7251.3 special requirements for distribution boards |
|---|---|
| Routine tests (every unit) | Insulation resistance, dielectric withstand, circuit-by-circuit continuity and leakage trip tests |
| Temperature rise | Terminal and busbar connections ≤70 K |
| Ingress protection verification | Outdoor type: door seal and incoming feed checked for rain and splash ingress |
| Documents with shipment | System diagram, terminal schedule, BOM, test report |
Five steps to specify your run
A configuration summary is generated as you go. It travels with your inquiry, saving a round of confirmation.
Build details
Systems have been in service for decades, and the failure points are always the same few: poor busbar contact, water ingress at the door seal, high temperature rise in the correction cabinet, and mis-phased outgoing feeders. The six hard rules below are written for exactly these points — every cabinet can be traced to them.
Circuits routed by zone, no shortcuts
Lighting circuits are split by bay, zone and street. A trip affects only one section, and the rest stays live during maintenance — circuit schedule delivered with the panel.
Crimped busbar connections, no flying leads
Outgoing circuits use a comb busbar with crimped connections instead of wire-by-wire daisy chaining. The enclosure stays clean no matter how many circuits, and later additions don't require tearing out existing wiring.
Correct trip curve for gas discharge lamps
Metal halide and sodium lamp ballasts draw a heavy inrush at startup. Circuits are fitted with D-curve breakers so the lights don't trip the moment they switch on — the most common field problem on lighting panels.
Bottom-entry only
Outdoor models use bottom-entry cable glands only, with a rain hood and gasket on the door, so water spray cannot reach live parts.
Continuity and RCD test on every unit
Every circuit is powered up and tested for continuity and with the residual current test button — all 36 ways, one by one, no sampling.
Spare capacity on DIN rail and terminals
20% spare positions on the DIN rail and terminals, so circuits can be added later without replacing the enclosure.
Photos & enclosure construction
Below are photos taken in our own shop — from the complete unit down to the internal busbars and secondary wiring. Every build detail can be checked item by item.
Image key: 01–05 are shop photos (the numbers match the shot list). The line drawing shows the front elevation of the enclosure; dimensions match the specification table above.
Where these cabinets go
These are the routine applications — we can talk scheme and configuration directly. For the industry view, see the industry pages.
Workshop and plant lighting
Zone control by bay keeps maintenance localized.
Plant and campus street lighting
Outdoor enclosure with timer and photocell control, sectional switching for midnight dimming.
Commercial floor lighting
Floor lighting split into circuits, with a separate after-hours circuit.
Warehouse and logistics facility
Zoned lighting for racking areas, circuits for high-bay luminaires.
Agricultural and greenhouse lighting
Outdoor IP65 with photocell control, moisture-resistant design.
Retrofit and replacement of old boxes
1:1 replacement following the original circuits, wire numbers unchanged.
Commercial terms
Specification dated September 2026; quotations follow this.
| Drawings & design | Free |
| MOQ | 1 unit (5 or more recommended for production) |
| Production lead time | 15-25 days after drawing approval |
| on-time delivery | 98% |
| Warranty | 12 months |
| Loading port | Ningbo / Shanghai, China |
| Component brands | Schneider / ABB / Siemens / Chint |
| Factory visit & dispatch confirmation | Factory visits welcome; finished-cabinet photos and video before dispatch |
| Capacity | 5,800+ units / year |
Documents for your engineering team
Selection manual, outline dimensions and RFQ checklist — for the customer's electrical engineer. All three documents are being organized by product line; download links go live once complete.
Six questions procurement and electrical engineers ask most
How does PZ30 relate to a lighting distribution box?
PZ30 is the legacy Chinese designation for a modular terminal combination assembly (terminal distribution box); the lighting distribution box is its most common application — the enclosure holds modular components such as miniature circuit breakers, mounted on DIN rail by module width. We build to your circuit requirements, and the construction is this same modular approach.
How should circuits be divided for a sound layout?
The principle: keep the impact of any single circuit failure contained, and keep the current on any one lighting circuit under 16 A. In workshops, divide by bay or zone; for street lighting, divide by street section; in commercial buildings, divide by tenant type. Send us your luminaire layout drawing and we will provide circuit division recommendations free of charge.
How should the main breaker be selected?
Size it on the simultaneous operating current of all circuits × the demand factor (typically 0.8–0.9 for lighting) plus margin; 32 A / 63 A are common. Where there are many gas discharge lamps, select D characteristic and go up one frame size to prevent inrush current from tripping the main breaker on closing.
Is ground fault protection required?
It is mandatory for outdoor and damp locations (street lighting, greenhouses, washdown areas): 30 mA branch ground fault protection or 100 mA main ground fault protection; for dry indoor lighting, follow the applicable code requirements. Whether to install ground fault protection at the main or on branch circuits depends on budget and the scope of any outage — we include a recommendation in our proposal.
Should I use a timer or a photocell?
For street lighting, a photocell plus timer combination is preferred: lights on at dusk (photocell), half switched off at a set time late at night (timer) — energy saving with minimal maintenance. A timer-only scheme is troublesome to adjust seasonally, and a photocell-only scheme switches on erroneously on overcast days. Astronomical time switches adjust automatically to sunrise and sunset and are the mainstream choice today.
Can it be controlled remotely?
Yes: fit the circuits with contactors and connect to a time switch, PLC or IoT gateway — we have solutions from single-luminaire control to whole-box control for street lighting. If you need energy and status reporting, state this at the inquiry stage and we will include metering and communication modules in the layout.
Other cabinet types in the same main circuit
Related products use color-block placeholders for now (product photos not yet complete; they will be replaced together). Internal links will be filled in once live URLs are confirmed.
Send us your luminaire layout drawing and we will provide circuit division free of charge
Send us your luminaire layout or circuit requirements and we will provide circuit division and an enclosure proposal free of charge · Quotation within 24 hours. Direct from our own factory, MOQ 1 unit, 15–25 day delivery, 1-year warranty.
ISO 9001:2015 · CE(LVD+EMC) · CQC · IP65
When you write, include: single-line diagram or primary scheme, switch room layout, load list, and component brand requirements. You do not need complete drawings — capacity and cabinet type are enough to start.