*Readers support Electric Vehicle Geek. When you buy with our links, we may earn a commission. Learn more.

*Read our review guidelines.

*Read our EV Chargers Safety Guidelines.

Connecticut Electric UBIF250N 50 Amp Circuit Breaker for Level 2 EV Charging

Add to compare
9.1
Expert ScoreRead review

The Connecticut Electric UBIF250N is a reliable 50A 2-pole replacement breaker for FPE NA panels. ETL listed, it handles 40A continuous EV charging loads and installs cleanly without panel mods.

The Connecticut Electric UBIF250N is a 50 Amp, 2-pole, thick-series Stab-Lok breaker made to replace Federal Pacific Electric NA-style breakers. It’s an ideal choice when installing a 240V 40A Level 2 EV charger or a 40A adjusted amperage Level 2 EV charger, especially in older homes with original Federal Pacific Stab-Lok panels. This breaker is newly manufactured—not reconditioned, and is ETL listed to UL 489 for use in the U.S. and Canada.

We recommend the UBIF250N when setting up a 240V 40A EV charger on a dedicated 240V 50A circuit. It fits securely in FPE load centers designed for NA-style thick breakers. The 2-inch body plugs in cleanly without looseness or poor contact, which are common in older Federal Pacific Electric panels. With a 10,000 AIC rating, this breaker meets the safety demands of high-powered charging loads required for Level 2 EV charging.

The UBIF250N is designed to replace the original Federal Pacific Electric NA250 breaker. That makes it a plug-and-play upgrade for NEC-compliant EV charger circuits in garages, carports, or dedicated EV charging subpanels.

We also tested this breaker with the Battery Tender eCharge 40 AMP EV Charger. This NEMA 14-50 plug-in charger delivers 9.6 kW when powered through a 50A circuit and plugged in a 14-50R outlet, the Battery Tender eCharge 40 AMP EV Charger performed flawlessly with no EV charger voltage dips, no 50A dedicated EV charger circuit breaker tripping, just steady, reliable 40A continuous loads charging even on extended durations of time. The breaker handled both the 32A and 40A EV charger loads with no performance issues.

Add to compare
Battery Tender eCharge 40 AMP EV Charger - Level 2 Mounted Indoor Outdoor Fast Electric Vehicle Charging Station with Flexible 25ft Cable NEMA 14-50 - 022-3018-DL-WH
Deal
The Battery Tender eCharge 40 AMP EV Charger is a high-performance Level 2 electric vehicle charger, designed for 240V power to deliver fast and efficient charging. Compatible with NEMA 14-50P or hardwired setups, this robust charger is perfect for both home and public use, offering reliable, high-speed charging for your EV.

In our wiring setup, we routed two #6 AWG hot wires and a #10 ground from the breaker to the NEMA 14-50R outlet that connects the Battery Tender eCharge 40 AMP EV Charger. The EV charger circuit wires ran through ¾” PVC conduit to the NEMA 14-50R outlet. No neutral was required for the 240V-only EVSE as shown in the wiring diagram below. The circuit was tested over 40+ charging hours with the Battery Tender eCharge 40 AMP EV Charger, and the breaker held firm with zero signs of wear or EV charging instability.This is a wiring diagram titled "40A EV Charger Wiring Diagram with UBIF0250N Breaker," illustrating how to connect a 40 Amp Level 2 Electric Vehicle charger to a Federal Pacific brand single-phase 240V electrical panel, following US National Electrical Code (NEC) guidelines. The diagram shows power entering the top of the main panel from the utility via three wires: L1 (Hot 1, black wire), L2 (Hot 2, red wire), and N (Neutral, white wire). These wires connect to the "Active Lugs on Main Breaker" located at the top of the panel interior. A yellow caution icon warns that these lugs remain electrically live regardless of whether the main breaker switch is on or off. Inside the electrical panel, the incoming power feeds the "Main Panel Breaker." Below the main breaker are vertical busbars where circuit breakers are installed. A "Neutral Busbar" is shown connected to the incoming neutral wire. A separate "G (Ground Busbar)" is also depicted. An "Electrical Bonding" jumper connects the Neutral Busbar to the Ground Busbar, which is standard practice in a main service panel. The Ground Busbar is connected via a green wire labeled "Earth Conductor" to an external "Ground Rod" driven into the "Ground/Earth," establishing the safety ground for the system. A specific circuit is set up for the EV charger using an "EV Charger Dedicated Circuit Breaker" identified as a "CB1 - 50A 2P Connecticut Electric (UBIF0250N)". This is a double-pole breaker, connecting to both hot busbars. The "240V EV Charger Branch Circuit" wiring exits this breaker. It consists of L1 (black wire), L2 (red wire), N (Neutral, white wire - though its connection to the neutral busbar isn't explicitly drawn, it's labeled as part of the circuit), and G (Ground, green wire connected to the Ground Busbar). These wires are specified as "EV Charger Circuit Wiring 6 AWG 90C, Copper Wire". The wires exit the panel through a "3/4" Conduit" fitting, shown being tightened by a hand in an inset photo. A note advises to upsize wires on long runs to mitigate "Voltage Drop" and keep it under 3% per NEC. Another caution sign advises keeping branch circuit wiring away from gutter posts and avoiding crossing wires over breakers inside the panel. The branch circuit wires (black, red, white, and green) are shown running towards a yellow NEMA 14-50 style receptacle, labeled "To EV charger (current flow)". To the right, an icon represents the "40 A Level 2 EV Charger" with its plug. This charger is noted as providing "9.6kW (240V = 40A)". A crucial yellow warning sign below this states, "40A charger needs a 50A breaker per NEC 80% rule," explaining why a 50A breaker is used for a 40A continuous load device. The bottom right confirms the diagram depicts "Single Phase Panel Wiring (US-NEC)". The logo for "Electric Vehicle Geek" appears in the bottom left corner.

Installation was quick and clean. The terminals on the UBIF250N are clamped down securely, there was no need to modify the panel, upgrade/replace the old panel, or worry about code violations—this breaker is made for FPE thick NA-style slots and installs without fuss.

This breaker is perfect for powering 9.60 kW EV chargers in homes where panel space and compatibility are tight, whether you’re using a plug-in EVSE like the Battery Tender eCharge 40 AMP EV Charger, or a hardwired 40A Level 2 Level 2 EV charger, the UBIF250N is a safe, reliable breaker option.

Wiring the UBIF250N Breaker for a 240V Level 2 EV Charger

Although we used a NEMA 14-50 EV charger to test the Connecticut Electric UBIF250N—a 50 Amp, 2-pole, thick-style Stab-Lok breaker designed to replace Federal Pacific NA-type breakers—there are other ways to wire your circuit depending on your electrical panel and Level 2 EV charger configurations. Below are the most common 240V EV charger wiring setups using this breaker.

EV Charger Wiring – 240V (3-Wire: L1, L2, Ground) – UBIF250N Breaker

This is the standard hardwired setup for Level 2 EV chargers that don’t require a neutral, including both hardwired Level 2 EV chargers and plug-in NEMA 6-50 EV chargers using a NEMA 6-50 outlet. For example, the Enphase IQ 50 which is a hardwired charger, and the Grizzl-E Classic which uses a NEMA 6-50 plug on a 50A circuit. Use 6 AWG solid copper wires: two hots (L1 and L2) from the UBIF250N breaker, and one ground wire connected to the panel’s ground busbar – as shown in the wiring diagram below:A detailed wiring diagram titled "EV Charger Wiring - 240V (3-Wire: L1, L2, Ground) - UBIF250N Breaker." The diagram illustrates the electrical setup for installing a 240V Level 2 EV charger. The diagram is centered around a grey 240V electrical panel. Power from the utility enters the panel from the top: L1 (Hot 1, black wire) and L2 (Hot 2, red wire) connect to "Active Lugs on Main Breaker." A white N (Neutral) wire also enters, connecting to the "Neutral Busbar." A yellow warning sign near the active lugs states: "Active lugs are continuously live, regardless of whether the main breaker is ON or OFF." Inside the panel: The "Main Panel Breaker" is at the top. Two vertical hot busbars run down the center. The "Neutral Busbar" is on the left, with multiple terminals. The "G (Ground Busbar)" is on the right, with multiple terminals. "Electrical Bonding" connects the neutral and ground busbars. An "Earth Conductor" (green wire) connects the ground busbar to a "Ground Rod" driven into "Ground/Earth." The "EV Charger Dedicated Circuit Breaker CB1 - 50A 2P Connecticut Electric (UBIF250N)" is a double-pole breaker installed across both hot busbars. From this dedicated 50A breaker, the "240V EV Charger Branch Circuit (L1, L2, & G)" exits the panel: L1 (black wire) from one pole of the breaker. L2 (red wire) from the other pole of the breaker. G (green wire) from the Ground Busbar. These wires are shown running through a "¾” Conduit," with a small inset photo of a hand working with conduit. A note indicates "EV Charger Circuit Wiring 6 AWG 90C, Copper Wire." Another note warns about "Voltage Drop - Upsize wires on long runs to keep voltage drop under 3% per NEC." A yellow warning sign near the panel exit advises: "Keep branch circuit wiring outside gutter posts and avoid crossing wires over breakers." The branch circuit wires (L1 black, L2 red, G green) lead towards the EV charger, with arrows indicating "To EV charger (current flow)." Two connection options are shown: Plug-in EV Charger: The wires connect to a "NEMA 6-50 Outlet" (diagram shows two vertical flat prongs and one D-shaped ground prong). A yellow box representing a "Plug-in EV Charger" connects to this outlet. Hardwired EV Charger: A note indicates "Hardwired EV Charger Terminal Wiring: L1 - LINE 1 (Black), L2 - LINE 2 (Red), G - GROUND (Green)." Both connection methods ultimately power a "40 A Level 2 EV Charger," specified as a "9.6kW EV charger (240V * 40A)." This is depicted by an icon of an EV charging connector. A yellow warning sign near the charger states: "40A charger needs a 50A breaker per NEC 80% rule." The bottom of the panel has the text "www.electricvehiclegeek.com" and "240V panel." In the bottom left corner is a logo for "ELECTRIC VEHICLE GEEK" featuring a stylized car and lightning bolt.

Compatible Level 2 EV Chargers for This Wiring Setup

Add to compare
JuiceBox 40 Smart Electric Vehicle (EV) Charging Station with WiFi - 40 amp Level 2 EVSE, 25-Foot Cable, UL & Energy Star Certified, Indoor/Outdoor Use (NEMA 14-50 Plug, Gray)…
Deal
The JuiceBox 40 Smart EV Charging Station delivers 40 amps of Level 2 charging with a 25-foot cable and NEMA 14-50 plug. UL and Energy Star certified, it provides efficient, safe charging for both indoor and outdoor use. WiFi connectivity enables smart features for optimized performance and energy management.
Add to compare
40 Amp Smart EV Charger - Enphase IQ 50, Hardwired, 9.6kW Power, 240V, 5-Year Warranty, Wi-Fi Connected, Safety Certified, 25ft Cable & Ruggedized J1772 Connector
Deal

The Enphase IQ 50 40 Amp Smart EV Charger delivers 9.6kW of power at 240V with a hardwired installation and a 25ft cable. Featuring Wi-Fi connectivity, a ruggedized J1772 connector, and safety certifications, it ensures reliable, efficient charging. Backed by a 5-year warranty, it's ideal for home use and future-proofing.

Add to compare
Grizzl-E Classic Level 2 Electric Vehicle (EV) Charger up to 40 Amp, UL Certified Indoor/Outdoor Electric Car Fast Wall Charging Station, NEMA 14-50 Plug, 24 feet Premium Cable, Avalanche Edition
Deal
The Grizzl-E Classic Level 2 EV Charger offers up to 40 Amps of fast charging with a 24-foot premium cable and NEMA 14-50/ NEMA 6-50 plug. UL-certified for safety, it’s designed for both indoor and outdoor use. The Avalanche Edition ensures rugged durability, making it perfect for reliable, high-speed EV charging.
Add to compare
ChargePoint Level 2 EV Charger J1772, Home Flex Nema 14-50 Electric Car Charger
Deal
The ChargePoint HomeFlex Level 2 EV Charger offers fast, reliable charging with a J1772 connector and NEMA 14-50 plug, delivering up to 30 miles of range per hour. UL-certified for safety, it’s designed for indoor/outdoor use and can be controlled via the ChargePoint mobile app. Compatible with the extensive ChargePoint network.
Add to compare
Autel MaxiCharger Home Electric Vehicle (EV) Charger, up to 50 Amp, 240V, Level 2 WiFi and Bluetooth Enabled EVSE, Hardwired, Indoor/Outdoor, 25-Foot Cable with Separate Holster, Dark Gray
Deal
The Autel MaxiCharger Home EV Charger offers up to 50 Amps of 240V Level 2 charging with WiFi and Bluetooth connectivity for smart, remote control. Designed for both indoor and outdoor use, it features a 25-foot cable, a separate holster, and a rugged dark gray finish, ensuring durability and efficient charging.

EV Charger Wiring – 240V (4-Wire: L1, L2, Neutral, Ground) – UBIF250N Breaker

This is the most common plug-in EV charger installation configuration for homes with original Federal Pacific Stab-Lok panels. Use this setup for Level 2 EV chargers that require a neutral, such as NEMA 14-50 plug-in EV chargers like the Grizzl-E Smart EV Charger – our top-rated home EV charger. The wiring of this EV charging circuit uses 6 AWG solid copper wires: two hot wires from the UBIF250N breaker, one neutral wire to the neutral busbar, and one ground wire to the ground busbar. This configuration supports both plug-in and hardwired installations, as shown in the wiring diagram below:A detailed wiring diagram titled "EV Charger Wiring - 240V (4-Wire: L1, L2, Neutral, Ground) - UBIF250N Breaker." The diagram illustrates the electrical setup for installing a 240V Level 2 EV charger using a 4-wire system. The diagram is centered around a grey 120/240V electrical panel. Power from the utility enters the panel from the top: L1 (Hot 1, black wire) and L2 (Hot 2, red wire) connect to "Active Lugs on Main Breaker." A white N (Neutral) wire also enters, connecting to the "Neutral Busbar." A yellow warning sign near the active lugs states: "Active lugs are continuously live, regardless of whether the main breaker is ON or OFF." Inside the panel: The "Main Panel Breaker" is at the top. Two vertical hot busbars run down the center. The "Neutral Busbar" is on the left, with multiple terminals. The "G (Ground Busbar)" is on the right, with multiple terminals. "Electrical Bonding" connects the neutral and ground busbars. An "Earth Conductor" (green wire) connects the ground busbar to a "Ground Rod" driven into "Ground/Earth." The "EV Charger Dedicated Circuit Breaker CB1 - 50A 2P Connecticut Electric (UBIF250N)" is a double-pole breaker installed across both hot busbars. From this dedicated 50A breaker and the panel's busbars, the "240V EV Charger Branch Circuit (L1, L2, N & G)" exits the panel: L1 (black wire) from one pole of the breaker. L2 (red wire) from the other pole of the breaker. N (white wire) from the Neutral Busbar. G (green wire) from the Ground Busbar. These four wires are shown running through a "¾” Conduit," with a small inset photo of a hand working with conduit. A note indicates "EV Charger Circuit Wiring 6 AWG 90C, Copper Wire." Another note warns about "Voltage Drop - Upsize wires on long runs to keep voltage drop under 3% per NEC." A yellow warning sign near the panel exit advises: "Keep branch circuit wiring outside gutter posts and avoid crossing wires over breakers." The branch circuit wires (L1 black, L2 red, N white, G green) lead towards the EV charger, with arrows indicating "To EV charger (current flow)." Two connection options are shown: Plug-in EV Charger: The wires connect to a "NEMA 14-50 Outlet" (diagram shows two vertical flat prongs, one L-shaped ground prong at the top, and one round neutral prong at the bottom). A yellow box representing a "Plug-in EV Charger" connects to this outlet. Hardwired EV Charger: A note indicates "Hardwired EV Charger Terminal Wiring: L1 - LINE 1 (Black), L2 - LINE 2 (Red), N - NEUTRAL (White), G - GROUND (Green)." Both connection methods ultimately power a "40 A Level 2 EV Charger," specified as a "9.6kW EV charger (240V * 40A)." This is depicted by an icon of an EV charging connector. A yellow warning sign near the charger states: "40A charger needs a 50A breaker per NEC 80% rule.

Compatible Level 2 EV Chargers for This Wiring Setup

Add to compare
Grizzl-E Smart Level 2 240V / 40A Electric Vehicle (EV) Charger, Metal Case UL Tested and Certified, Energy Star, Indoor/Outdoor Electric Car Fast Charging Station, NEMA 14-50, Avalanche
Deal
The Grizzl-E Smart Level 2 EV Charger (240V, 40A) is a robust and efficient home charging solution engineered for reliability and universal compatibility via its J1772 connector. Housed in a rugged, weather-resistant aluminum enclosure, it is UL-listed, Energy Star certified, and supports both NEMA 14-50 and NEMA 6-50 plug types - making it ideal for indoor or outdoor installations requiring fast and dependable EV charging.
Add to compare
Battery Tender eCharge 40 AMP EV Charger - Level 2 Mounted Indoor Outdoor Fast Electric Vehicle Charging Station with Flexible 25ft Cable NEMA 14-50 - 022-3018-DL-WH
Deal
The Battery Tender eCharge 40 AMP EV Charger is a high-performance Level 2 electric vehicle charger, designed for 240V power to deliver fast and efficient charging. Compatible with NEMA 14-50P or hardwired setups, this robust charger is perfect for both home and public use, offering reliable, high-speed charging for your EV.
Add to compare
MUSTART Level 2 EV Charger, 40 Amp, 240 Volt, 25ft Cable, Electric Vehicle Portable Charger Plug-in EV Charging Station with NEMA 14-50P, ETL Certificated
Deal
The Mustart 40 Amp EV Charger delivers fast 240V charging with a 25-foot cable and NEMA 14-50P plug for easy installation. ETL-certified for safety, this portable plug-in station is ideal for home use, providing reliable, high-speed charging for all-electric vehicles with convenience and efficiency.
Add to compare
EMPORIA Level 2 EV Charger - NEMA 14-50 EVSE w/ J1772 Charger - 48 amp EV Charger Level 2, 240v WiFi Enabled Electric Vehicle Charging Station, 24ft Electric Car Charger Cable, White
Deal
The EMPORIA Level 2 EV Charger delivers 48 amps of 240V charging with a 24ft cable and NEMA 14-50 plug. WiFi-enabled for smart features and remote monitoring, this J1772-compatible EVSE offers fast, reliable charging for electric vehicles. Ideal for home installations, it ensures efficient and convenient EV charging.
Add to compare
EMPORIA Pro Level 2 EV Charger with PowerSmart - 48 amp Fast Charger with NEMA 14-50 or Hardwire and J1772 Connector - 240v Electric Vehicle Charging Station and 25' EV Charging Cable
Deal
Emporia Pro EV Charger offers 48A fast Level 2 EV charging with PowerSmart Load Management. Includes NEMA 14-50 plug or hardwire installation options, 25' cable, and real-time energy optimization for efficient charging.

EV Charger Wiring – 240V (3-Wire: L1, L2, Neutral, No Ground) – UBIF250N Breaker

This older method includes two hots and a neutral one with no ground. It may exist in legacy NEMA 10-50 EV charger installations using original Federal Pacific Stab-Lok panels where neutral is bonded to the ground. Not recommended by current NEC standards. Use only if the charger supports it and local code allows — as shown in the wiring diagram below:A detailed wiring diagram titled "EV Charger Wiring - 240V (3-Wire: L1, L2, Neutral, No Ground) - UBIF250N Breaker." The diagram illustrates an outdated and potentially unsafe electrical setup for installing a 240V Level 2 EV charger using a 3-wire system without a dedicated ground wire to the appliance. The diagram is centered around a grey 240V electrical panel. Power from the utility enters the panel from the top: L1 (Hot 1, black wire) and L2 (Hot 2, red wire) connect to "Active Lugs on Main Breaker." A white N (Neutral) wire also enters, connecting to the "Neutral Busbar." A yellow warning sign near the active lugs states: "Active lugs are continuously live, regardless of whether the main breaker is ON or OFF." Inside the panel: The "Main Panel Breaker" is at the top. Two vertical hot busbars run down the center. The "Neutral Busbar" is on the left, with multiple terminals. The "G (Ground Busbar)" is on the right, with multiple terminals. "Electrical Bonding" connects the neutral and ground busbars. An "Earth Conductor" (green wire) connects the ground busbar to a "Ground Rod" driven into "Ground/Earth." (This indicates the panel itself is grounded). The "EV Charger Dedicated Circuit Breaker CB1 - 50A 2P Connecticut Electric (UBIF250N)" is a double-pole breaker installed across both hot busbars. From this dedicated 50A breaker and the neutral busbar, the "240V EV Charger Branch Circuit (L1, L2, & N)" exits the panel: L1 (black wire) from one pole of the breaker. L2 (red wire) from the other pole of the breaker. N (white wire) from the Neutral Busbar. Crucially, no separate green ground wire is shown in this branch circuit. These three wires are shown running through a "¾” Conduit," with a small inset photo of a hand working with conduit. A note indicates "EV Charger Circuit Wiring 6 AWG 90C, Copper Wire." Another note warns about "Voltage Drop - Upsize wires on long runs to keep voltage drop under 3% per NEC." A yellow warning sign near the panel exit advises: "Keep branch circuit wiring outside gutter posts and avoid crossing wires over breakers." The branch circuit wires (L1 black, L2 red, N white) lead towards the EV charger, with arrows indicating "To EV charger (current flow)." Two connection options are shown: Plug-in EV Charger: The wires connect to a "NEMA 10-50 Outlet" (diagram shows two angled flat prongs labeled Y and X, and one L-shaped prong labeled W, typically used for Neutral/Ground combined). A yellow box representing a "Plug-in EV Charger" connects to this outlet. Hardwired EV Charger: A note indicates "Hardwired EV Charger Terminal Wiring: L1 - LINE 1 (Black), L2 - LINE 2 (Red), N - NEUTRAL (White)." Both connection methods ultimately power a "40 A Level 2 EV Charger," specified as a "9.6kW EV charger (240V * 40A)." This is depicted by an icon of an EV charging connector. A yellow warning sign near the charger states: "40A charger needs a 50A breaker per NEC 80% rule." A prominent yellow warning sign at the bottom right of the diagram states: "The configuration (L1, L2, N - no ground) is outdated and not permitted under modern NEC requirements for EV chargers. According to NEC 250.4(A)(1) and NEC 625.54, grounding is essential for all electrical installations, including EV chargers. Avoid using this setup in new installations.

9.1Expert Score
The Connecticut Electric UBIF250N is a reliable 50A 2-pole replacement breaker for FPE NA panels. ETL listed, it handles 40A continuous EV charging loads and installs cleanly without panel mods.
Features
9
Real World Usage
9.5
Materials
9.5
Durability
9
Craftsmanship
9
Design
9
Monetary Value
9
Product Value
9
Brand Reputation
8.5
Expert Valuation
9.5
PROS
  • Plug-and-play fit for thick-style FPE Stab-Lok NA panels.
  • Supports continuous 40A loads with zero nuisance tripping.
  • ETL listed to UL 489—certified for North American safety.
  • Installs cleanly without modifying legacy panels.
CONS
  • Only fits thick-series NA-style FPE breakers—limited compatibility.
  • Does not support AFCI or GFCI protection out-of-the-box.
  • Pricier than other 50A circuit breakers from the same brand.

User Reviews

0.0 out of 5
0
0
0
0
0
Write a review

There are no reviews yet.

Be the first to review “Connecticut Electric UBIF250N 50 Amp Circuit Breaker for Level 2 EV Charging”

Your email address will not be published. Required fields are marked *

Electric Vehicle Geek
Logo
Compare items
  • Total (0)
Compare
0