Eaton Plastic Case Circuit Breaker Technology Analysis and Application Guide

In terms of DC applications, the Power Defense framework supports DC distribution of 250 Vdc and below, and can achieve higher voltage through series connection of poles (such as PD-3/PD-4, which can reach 800 Vdc through 4-pole series connection).

1.5 Modular Attachment System

The accessory system of Power Defense is highly unified, and the same accessory can be used across multiple frameworks, greatly simplifying on-site configuration and inventory management.

Instruction attachment (right cavity)

Auxiliary switch: configured with 1NO+1NC (Form C) or 2NO+2NC, used for remote indication of circuit breaker status.

Alarm switch: It operates when the circuit breaker trips due to a fault, and automatically resets after manual reset.

Release attachment (left cavity)

Split release: Remote control circuit breaker tripping, suitable for emergency disconnection or interlocking systems.

Undervoltage release: When the voltage drops to 35%~70% of the rated value, the circuit breaker trips to prevent undervoltage operation.

All attachments provide various wiring methods such as 30 inch (0.75m) or 118 inch (3m) fly wires, screw terminals, spring clip terminals, etc.

1.6 Communication and Software Ecology

Power Defense is not only a protective device, but also a node of intelligent distribution network. PXR 20/25 supports accessing the following networks through CAM (Communication Adapter Module):

Modbus TCP/IP（ECAM）

PROFIBUS DP（PCAM）

With Eaton's Power Xpert Protection Manager (PXPM) software, users can:

Online modification of protection settings

Perform secondary injection testing

View real-time energy data

Analyze event waveform

Generate test report

Chapter 2 Series G and Series C: Inheritance and Transition of Classic Series

2.1 Series G: Compact Design for Global Use

Series G is Eaton's molded case circuit breaker series launched for the global market, represented by "G" for Global. Its core advantages lie in:

Compact size: reduces installation space by an average of 35% compared to traditional circuit breakers.

Universal attachments: Frame attachments below 630A are universal, simplifying selection.

Electronic release: Equipped with Digittrip RMS 310+, it has functions such as true effective value measurement, curve tuning, and thermal memory.

Current range: EG (15-125A), NG (320-1200A), RG (800-2500A).

NG and RG frameworks can be equipped with LSI, LSIG, ALSI and other models of Digitrip RMS 310+. Among them, the ALSI model has a built-in Arcflash Reduction Maintenance System, which can be activated by remote signals to reduce the instantaneous setting value to 2.5 times the rated current, effectively reducing arc flashover energy.

2.2 Series C: A classic that is about to be delisted

Series C is Eaton's classic product line, covering 15A to 2500A, including multiple frames such as G, F, J, K, L, and M. According to the catalog, multiple frameworks of Series C are scheduled to be delisted in 2026, but complete replacement support will still be provided. Its typical characteristics include:

Thermal magnetic trip and electronic trip: such as FD series thermal magnetic circuit breakers, with a maximum breaking capacity of 200kA (480V); The FDCE series electronic release supports LSI/LSIG.

Motor protection dedicated: HMCP series motor circuit protector, designed specifically for use with contactors, can provide instantaneous overcurrent protection from 3A to 1200A.

DC application: HFDDC, HJDDC and other DC specific models can meet the protection requirements of 125V to 750V DC systems.

2.3 Special Circuit Breaker

2.3.1 DC Circuit Breaker

Suitable for UPS, photovoltaic, electric vehicle charging and other scenarios, with a maximum voltage of 800Vdc and a maximum current of 3000A (RGHDC frame). High voltage breaking is achieved through series connection of poles, such as the 800Vdc four pole series connection scheme of PD-3/PD-4.

2.3.2 PVGard Photovoltaic Circuit Breaker

Specially designed for photovoltaic systems, meeting UL 489B standards and capable of reliable operation in ambient temperatures ranging from -40 ° C to+90 ° C. The 1000Vdc four pole series model provides a breaking capacity of 3kA to 7.5kA, supports bidirectional current, and is suitable for series protection.

2.3.3 E2 Mining Circuit Breaker

Meets MSHA 30 CFR 75 specifications and is designed specifically for harsh environments such as coal mines. Using electronic release, the instantaneous setting value strictly meets the protection requirements of the towing cable, and the breaking capacity can reach up to 1200V 10kA. The E2 series provides comprehensive coverage from E2F (15-150A) to E2R (1600-2000A).

Chapter 3 Attachments and Extended Functions

3.1 Types of Wiring Terminals

Power Defense offers multiple terminal options to accommodate different wiring needs:

Standard terminal: made of steel or aluminum material, suitable for copper or aluminum wires.

Multi wire terminal: allows one pole to connect multiple wires (such as 3 or 6), replacing the distribution terminal block.

StrandAble terminal: designed specifically for thin twisted wires to ensure reliable connection.

Rear wiring terminal: used for rear wiring and needs to be used in conjunction with a partition.