PCC power control center
- Main switch: drawout air circuit breaker (ACB) ≤4000 A, breaking capacity matched to system short-circuit capacity
- Cabinet: same module as GGD / GCS for section assembly, factory-prefabricated through-busbars
- Bus tie scheme: two busbar sections mutually backed up via bus tie cabinet, auto-transfer or manual on loss of power
- Monitoring: three-phase current/voltage, power, and energy full-parameter meter, RS485 reporting
- Short-time withstand: Icw matched to main switch (up to 80 kA), temperature rise ≤70 K
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.
| Type | PCC floor-standing incoming / bus tie cabinet, assembled in the same section as GGD / GCS |
|---|---|
| Standard sizes (W×D×H) | 1000×800(1000)×2200 mm (incoming cabinet), custom build available |
| Enclosure construction | Profile frame, busbar compartment / breaker compartment / cable compartment separated |
| Main switch type | Drawout air circuit breaker, rack in / rack out mechanism with interlocks |
| IP rating | IP30 / IP42 (electrical room) |
| Cable entry | Transformer-side busbar / large cable bottom entry, feeder busbar continuous through |
| Rated voltage | AC 400V, 50 Hz |
|---|---|
| Main incoming device | Drawout air circuit breaker 630–4000 A |
| Short-time withstand current, Icw | 50 / 65 / 80 kA (matched to the main breaker interrupting capacity) |
| Main busbar | TMY tinned copper busbar sized by current, torqued to 30–40 N·m with mark-off lines |
| Bus tie configuration | Two busbar sections cross-fed through a bus tie cabinet, automatic transfer (with protection interlock) or manual |
| Protection configuration | Air circuit breaker with smart trip unit (LSIG: long-time / short-time / instantaneous / ground) |
| Monitoring | Full-parameter meter (U/I/P/Q/cosφ/energy), RS485 / Modbus reporting |
| Component brands | Schneider / ABB / Siemens air circuit breakers, customer-specified brands supported |
| Single-transformer incoming type | One transformer per busbar section, PCC incoming + GGD/GCS feeders |
|---|---|
| Dual-transformer bus tie type | Two busbar sections + bus tie cabinet cross-feed, automatic transfer on loss of supply or manual paralleling |
| Combined incoming + metering type | Metering integrated in the incoming cabinet (utility-side gateway meter per local requirements) |
| Drawout feeder type | Feeders in the PCC section also drawout (mixed with GCS) |
| Retrofit / breaker replacement type | Replace air circuit breakers and protection in existing PCC cabinets, busbar reuse assessed |
| Assembly standard | GB/T 7251.1 / IEC 61439-1, main circuit verified to type-test criteria |
|---|---|
| Interlock verification | Drawout mechanism rack-in/rack-out interlock, position signals verified cabinet by cabinet |
| Busbar testing | Torque mark-off lines + busbar temperature rise calculation (≤70 K) |
| Routine tests (every unit) | Insulation resistance, withstand voltage 2500V/1min, trip unit operating characteristics |
| Documents with shipment | Single-line diagram, protection setting table, busbar specification, 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.
Busbar torque fastening, re-checkable
Main busbar torqued to 30–40 N·m and marked point by point: during inspection, a glance at the line shows whether anything has loosened. On high-current cabinets the contact surface is the critical point — we do not skip this step.
Full-load based, not rule of thumb
The 4000 A busbar is calculated for temperature rise at full load (≤70 K), and the busbar datasheet ships with the cabinet. High-current cabinets cannot tolerate "close enough" — a small margin shortfall means a trip on a hot summer day.
LSIG tested unit by unit
The electronic trip unit's long-time / short-time / instantaneous / ground fault four-stage protection is tested for operating characteristics on every unit, and the settings are recorded in the setting table — this is what makes upstream/downstream coordination work.
Cannot rack in while energized
Drawout mechanism position interlock: the door cannot be opened in the connected position, and maintenance is only possible in the test position. Operator safety on high-current cabinets depends entirely on the mechanism — verified unit by unit.
No risk when paralleling buses
Bus tie auto-transfer is equipped with a protection interlock (buses may only be paralleled when both sections are healthy), preventing a faulted bus from being paralleled to a healthy bus — reliability design always takes priority over automation.
Assembled as a full section at the factory
Assembled in the same factory as the feeder cabinets: continuous busbar, full-section dielectric test, unified nameplate — on site it is lifted into place, connected, and energized. This is work that cannot be done when sourcing sections separately.
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.
Factory main distribution room
First stop on the transformer secondary — the backbone of the whole lineup.
Large workshop substation
Multiple busbar sections + bus tie for mutual backup.
Data Centers / Server Rooms
Dual-source PCC sections + row-level panelboard system.
Commercial complexes
Center distribution with multiple transformers split into sections.
Municipal pump stations / water treatment plants
High-capacity incoming lines and distribution to critical loads.
Section retrofit
Replace PCC incoming cabinet + protection upgrade, with busbar reuse assessment.
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
What is the difference between PCC and MCC?
PCC (Power Control Center) handles the incoming side: high-current incoming lines and busbar distribution. MCC (Motor Control Center) handles the outgoing side: centralized control of motor circuits (drawer units). A single electrical room is often a combination of PCC incoming + MCC / GCS feeders — we build both ends and assemble the sections in-house.
Why drawout for air circuit breakers?
Drawout (rack in / rack out): breakers can be serviced or replaced without dismantling the busbars — rack it out and swap it, with interlocks to prevent live operation. Fixed-type is cheaper, but replacing a breaker means a shutdown and busbar teardown. For incoming cabinets — positions that move maybe a few times a year but matter enormously when they do — drawout is worth it.
Do two transformers always need a bus tie?
Not always, but if mutual backup is required, we recommend it: when one section loses power, the bus tie closes (manual or auto-transfer with blocking), keeping critical loads energized. Auto-transfer on the bus tie must include protection blocking and synchronization conditions — we issue the settings as part of the system design, never a bare transfer.
What if the load exceeds 4000 A?
4000 A is already the common upper limit for low-voltage cabinets. Beyond that, two paths: split transformer operation (two sections at 4000 A class each), or busway risers + floor-level distribution cabinets. Send us the transformer capacity and load distribution, and we will recommend the sectioning.
Is arc flash protection necessary?
It is standard on medium voltage switchgear. For high-current low-voltage PCC sections (above 2500 A, unattended), we recommend arc flash sensors + fast tripping: arc faults are cleared from inception to trip in tens of milliseconds — an order of magnitude difference in personnel and equipment damage. On a tight budget, at minimum reserve the interfaces.
What can intelligent monitoring show?
Full electrical parameters (three-phase U/I/P/Q/cosφ/energy) + breaker status + trip unit event logs, reported via RS485/Modbus to power monitoring or the BA system; busbar temperature sensing is optional. Operations can see the health of the entire section from the control room — inspections are no longer done blind.
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 the system diagram — we will deliver the full section design together
Send us your single-line diagram or transformer capacity for a free PCC incoming and full-section distribution design · Quotation within 24 hours. Direct from the source 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.