Type C is the workhorse curve in many commercial and light-industrial distribution boards. It provides more inrush tolerance than Type B without moving to the much higher magnetic threshold of Type D. That balance makes it useful, but not universal: a Type C breaker still has to protect the cable, interrupt the available fault current and meet the required disconnection time.

Type C thermal and magnetic operation

The thermal element responds to sustained overload. The magnetic element responds to high short-circuit current. For a C16, the magnetic operating band is about 80-160 A; for a C32, it is about 160-320 A. These figures describe the instantaneous band, not a permissible continuous load.

Where Type C is commonly used

• Office and retail socket-outlet circuits with mixed electronic and small motor loads.

• LED and fluorescent lighting groups where simultaneous energization creates a brief charging current.

• Small pumps, fans, garage-door operators, refrigeration equipment and light machinery.

• Control panels and sub-distribution circuits with moderate transformer or contactor inrush.

• Three-phase equipment using PL10-C16/3, PL10-C25/3 or PL10-C32/3 when current, coordination and fault level support the choice.

How to specify the exact model

Worked selection example

Assume a single-phase pump draws 11 A in normal operation and reaches 62 A for a short start. A B16 may enter its magnetic band from 48 A, so nuisance tripping is possible. A C16 has an 80-160 A magnetic band and may ride through the 62 A start. Before selecting PL10-C16, the designer must still verify conductor ampacity, motor overload protection, fault-loop conditions and the 10 kA breaking-capacity requirement. If both live conductors must open together, the candidate becomes PL10-C16/2 rather than PL10-C16.

When Type C is the wrong choice

• A low-inrush circuit with limited fault current may need Type B for faster magnetic operation.

• A transformer or high-inertia motor with repeated inrush above the C-curve band may require Type D or a dedicated motor-protection solution.

• A large industrial load may need an IEC 60947-2 MCCB rather than an IEC 60898-1 MCB.

• A motor still needs the overload, phase-loss and coordination protection required by the design; an MCB curve alone does not replace a motor-protection scheme.

Frequently Asked Questions

What does C32 mean on a breaker?

C is the instantaneous curve and 32 is the rated current in amperes. In the Eaton PL10 range, PL10-C32 identifies the one-pole model, while PL10-C32/3 identifies a three-pole model.

Can Type C be used in a home?

It can be used where the installation rules, fault-loop conditions and load inrush justify it. Type B remains common for low-inrush domestic circuits.

Is PL10-C63/4 an RCD?

The cited PL10-C63/4 product is an MCB model with a C curve, 63 A rating and four poles. Residual-current protection requires an RCD/RCBO or another specified residual-current device.

Should I choose C16 or C20 for a 16 A load?

Do not increase the breaker only to avoid trips. Calculate design current and cable ampacity, account for derating and evaluate the actual cause of tripping before changing rating.

Bottom line

Type C is a balanced choice for moderate inrush. The commercial selection is complete only when curve, current, poles, breaking capacity, accessories and installation conditions have been translated into an exact model such as PL10-C16, PL10-C32/3 or PL10-C63/4.

For a PL10 model recommendation, provide ASBEAM with the system voltage, phase arrangement, full-load current, measured inrush, cable data and prospective fault current.

Technical references

• ASBEAM - PL10-C32 product specifications

• ASBEAM - PL10 B/C/D current and pole matrix