Ask five people on a factory floor what the difference between a PCC and an MCC is and you will get five answers. Both are low voltage switchboards, both are made of sheet steel and busbars, and both often sit in the same room. But they do different jobs, and mixing them up leads to wrong orders, wrong quotes and panels that do not suit the plant.
Here is the plain version.
The short answer
A PCC (Power Control Centre) receives power from the transformer or the generator and distributes it. An MCC (Motor Control Centre) takes that power and starts, protects and controls motors. In most plants the PCC feeds the MCC, not the other way round.
What a PCC does
The PCC is the main switchboard. It carries the incoming supply on a large busbar and feeds the rest of the plant through circuit breakers. A typical PCC has:
- an incomer, usually an air circuit breaker (ACB) for larger loads
- a main busbar sized for the full plant current
- outgoing feeders to the MCC, to lighting and utility boards, and to large individual loads
- metering and protection relays on the incomer
The main design questions are current rating, short circuit withstand and how the busbar behaves when it is hot. We cover that last point in busbar de-rating. You can see what we build on our PCC panel page.
What an MCC does
The MCC is built around motors. Each motor gets its own compartment, usually called a feeder or module, with a short circuit protective device, a contactor, an overload relay and the control wiring. Depending on the motor, the feeder can be:
- DOL (direct on line) for small motors
- star-delta for medium motors where starting current must be reduced
- soft starter or VFD for motors that need controlled starting or speed control
The design questions here are different: how the starter is coordinated with its protection (Type 1 vs Type 2), how easily one feeder can be isolated and replaced, and how the control side talks to a PLC. See our MCC panel page for the range.
PCC vs MCC at a glance
| Point | PCC | MCC |
|---|---|---|
| Main job | Receive and distribute power | Start, protect and control motors |
| Position in the plant | Upstream, close to the transformer or generator | Downstream, fed from the PCC |
| Typical devices | ACB, MCCB, protection relays, meters | Contactors, overload relays, VFDs, soft starters, MCCBs or fuses |
| Typical build | Large busbar, fewer but heavier feeders | Many compartments, one per motor, with control wiring |
| Key design concern | Current rating and fault withstand | Starter coordination, ease of maintenance, control integration |
Do you need both?
Usually yes, if the plant has a transformer and a meaningful number of motors. A small workshop with a handful of motors might run with a single distribution board and a few standalone starters. A mill, a pump house or a process plant almost always wants a PCC at the front and one or more MCCs behind it.
A few practical pointers:
- Count the motors and note which ones need VFDs or soft starters, as that decides the MCC layout.
- Ask for the short circuit level at the incomer, since both panels must be rated for it. See CPRI type testing for why testing matters.
- Decide how much isolation you need during maintenance. Form separation explains the options.
Not sure what you need?
Send us your single line diagram or your motor list and our engineers will tell you what is needed and what is not. Contact us and we will come back with questions before we come back with a quote.
Frequently asked questions
What is the main difference between a PCC and an MCC panel?
A PCC receives power from the transformer or generator and distributes it to the plant. An MCC starts, protects and controls motors. The PCC is normally upstream and feeds the MCC.
Can an MCC be fed directly from the transformer without a PCC?
In small installations it can be, through a main breaker or incomer on the MCC itself. In larger plants a separate PCC is the better choice, because the incomer protection, metering and other feeders then have their own board.
Is a PCC the same as an LT panel or a main distribution board?
The terms overlap in everyday use. A PCC is a main low voltage distribution switchboard, and people also call it an LT panel or MDB. What matters is the scope: incomer, busbar and feeders. Confirm that scope when you ask for a quote.
Does an MCC always need a PLC?
No. Many MCCs work with conventional push buttons and relays. A PLC is added when the plant needs automation, interlocking between motors or remote monitoring. The MCC can be built ready for it.
Which standard applies to these panels?
Low voltage switchgear and controlgear assemblies are covered by IEC 61439. Motor starters inside an MCC are covered by IEC 60947-4-1. Ask your supplier which standard and which test evidence the panel is offered against.
Talk to our engineers about your panel requirement
We design, build and type-test LT panels in-house in Rajkot. Send us a single line drawing or a load list and we will come back with a technical assessment.
