Eaton FG3125 Engine Generator MCCB - UL Listed, 18 kAIC
Part Number: FG3125
Quick Summary
The Eaton FG3125 Engine Generator Molded Case Circuit Breaker protects engine-driven electrical systems by interrupting fault currents. For engineers protecting generator sets, inconsistent trip performance and wiring challenges in control panels are common pain points. This device is UL Listed, CSA Certified, and IEC rated, with MIL-DTL-17361 compliance to support global installations. Built around a 60 Hz, three-pole FG frame, it simplifies panel integration while delivering robust protection. In business terms, it reduces downtime, streamlines procurement, and helps meet regulatory requirements across North America and beyond.
Product Information
Extended Description
FG3125 Eaton: Eaton Series C complete EG molded case circuit breaker, F-frame, FG, Fixed thermal and magnetic trips, Three-pole, 125A, 600 Vac, 18 kAIC at 240 Vac, 14 kAIC at 480 Vac, Line/load, Engine generator, Reverse, 60 Hz, Fixed
Product Name
Eaton complete engine generator molded case circuit breaker
Catalog Number
FG3125
UPC
786679269787
Product Length/Depth
7.7 in
Product Height
4.8 in
Product Width
4.9 in
Product Weight
4.3 lb
Warranty
Eaton Selling Policy 25-000, one (1) year from the date of installation of the Product or eighteen (18) months from the date of shipment of the Product, whichever occurs first.
Compliances
MIL-DTL-17361
Certifications
CSA Certified UL Listed IEC Rated CSA Std. C22.2 No. 5 IEC 947-2 UL Listed file E7819 UL 489 QPL17361
Catalog Notes
Includes both line and load terminals
Type
Engine generator
Amperage Rating
125 A
Voltage rating
600 Vac
Trip Type
T186
Circuit breaker type
FG
Circuit breaker frame type
Complete breaker
Terminals
Line and load
Frame
F
Frequency rating
60 Hz
Class
Engine generator
Pickup
Fixed
Interrupt rating
18 kAIC at 240 Vac 14 kAIC at 480 Vac
Generator rating
45 kVA/36 kW at 240V, 90 kVA/72 kW at 480V, 113 kVA/90 kW at 600V
Number of poles
Three-pole
Functions
Reverse
Engine generator circuit breakers catalog
Circuit Breakers Explained
Eaton Specification Sheet - FG3125
Feature: Fixed thermal and magnetic trips provide reliable fault interruption with a 60 Hz operating basis. Business Impact: Quick, predictable protection minimizes damage to generators and connected loads, lowering maintenance costs. Application: Ideal for engine-generator panels in industrial plants with frequent start/stop cycles. Feature: Includes line and load terminals and a complete FG frame for easy wiring. Business Impact: Simplifies installation and testing, reduces panel space, and accelerates commissioning. Application: Retrofit and new builds where motor and generator loads share protection devices. Feature: Amperage and voltage ratings—125 A at 600 Vac with 18 kAIC at 240 Vac and 14 kAIC at 480 Vac. Business Impact: Supports a wide range of generator outputs while meeting short-circuit withstand requirements. Application: Engine-generator protection in 60 Hz systems. Feature: Certifications and MIL-DTL-17361 compliance ensure regulatory alignment. Business Impact: Lowers procurement complexity and compliance risk across multi-region projects. Application: Global deployments and cross-border installations. Feature: Warranty and service terms with a clear policy (25-000). Business Impact: Predictable support and total cost of ownership improvements. Application: Asset management and long-term maintenance planning. Feature: Engine-generator focus with a three-pole FG frame and fixed pickup. Business Impact: Compact, reliable protection designed for generator-control panels. Application: Panel builders seeking durable protection in harsh environments.
Get a Quick Quote for a Eaton FG3125
Chat with us on WhatsApp - fast responses guaranteed
Need to speak with someone? We'll call you back within 2 hours during business hours
Interested in Eaton FG3125?
Enquire Now
FAQs
FG3125 uses line and load terminals and a three-pole FG frame designed for engine-generator panels. Plan for proper conductor sizing, torque on terminal screws, and clearance around the device to accommodate same-space mounting and easy access for testing. Ensure compatible control wiring and follow MIL-DTL-17361 and IEC guidance for wiring practices in generator environments.
The FG3125 features fixed trip pickup (T186) with 125 A rating, 600 Vac, and high short-circuit withstand (18 kAIC at 240 Vac, 14 kAIC at 480 Vac). This combination provides fast fault interruption, protecting both the generator and connected loads during startup surges and grid disturbances typical in 60 Hz applications.
Yes. The FG3125 is UL Listed and CSA Certified, IEC rated, and MIL-DTL-17361 compliant, aligning with both North American and international requirements. This certification mix supports global procurement, reduces supplier diversification, and helps meet regulatory obligations in diverse markets.
The FG3125 carries Eaton’s warranty policy 25-000, providing one year from installation or eighteen months from shipment, whichever occurs first. This structure helps with long-term maintenance budgeting and ensures access to manufacturer support during the critical early life of generator protection equipment.
The FG3125 is 7.7 inches long, 4.8 inches high, and 4.9 inches wide, with an approximate weight of 4.3 pounds. These compact dimensions support straightforward mounting in standard engine-generator panels and enable efficient space planning during panel design or retrofits.