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Manufacturer Resources
Spec Sheet
Product Specs
- Amperage Rating:
- 125A
- Circuit Breaker Frame Type:
- Complete breaker
- Circuit Breaker Type:
- FDB
- Frame Size:
- F-frame
- Frequency Rating:
- 50/60 Hz
- Interrupt Rating:
- 18 kAIC at 240 Vac, 14 kAIC at 480 Vac
- Number Of Poles:
- Two-pole
- Series:
- Series C
- Terminals:
- Load side
- Trip Type:
- Fixed thermal, fixed magnetic
- Voltage Rating:
- 600 Vac, 250 Vdc
- Department:
- Electrical
- Product Length:
- 3.38 IN
- Product Height:
- 2.75 IN
- Product Weight:
- 3 LB
- Product Width:
- 2.75 IN
B-LINE FDB2125 – Frequently Asked Questions
1) What interrupting rating does the Eaton FDB2125 breaker have at 480V?
The FDB2125 is rated 14 kAIC at 480 Vac and 18 kAIC at 240 Vac. If your available fault current at the panel exceeds those numbers, the FDB frame is the wrong choice and you need a higher-interrupting F-frame breaker (the FD and HFD variants of the same footprint carry higher AIC). Full voltage rating is 600 Vac, 250 Vdc.
2) Is the FDB2125 adjustable, or is the trip setting fixed?
Fixed on both halves: fixed thermal and fixed magnetic trip. There is no adjustable instantaneous dial, so the 125A rating is what you get. If your spec calls for an adjustable magnetic setting to ride through motor inrush, an FDB will not satisfy it.
3) Will the FDB2125 fit in my existing enclosure?
Body dimensions are 3.38 inches long by 2.75 inches high by 2.75 inches wide, and it weighs 3 pounds. That is the standard Eaton F-frame envelope, so it drops into any interior or enclosure prepped for a two-pole F-frame breaker. Allow working clearance for the load-side conductors on top of those numbers.
4) I need to match a breaker stamped FDB2125 in an Eaton panel. Is this the same part?
Same part number, FDB2125, Eaton Series C, two-pole 125A F-frame. Series C is the family Eaton has built the FD line under for decades, so a direct replacement of an existing FDB2125 is straightforward. Check the AIC stamped on the breaker you are pulling out, since FD, FDB and HFD share the footprint but not the interrupting rating.
5) Does the FDB2125 come as a complete breaker or just a trip unit?
It ships as a complete molded case circuit breaker, F-frame, Eaton Series C. You are not buying a frame that needs a separate rating plug or trip unit added. Mounting hardware, lugs beyond what is supplied, and any accessories like shunt trips, auxiliary switches or handle mechanisms are ordered separately.
6) What terminals does the FDB2125 come with?
Load side terminals are what the breaker is supplied with. Line side connection is made through the panel or the mounting arrangement, so confirm your enclosure or panelboard interior before you plan the cable landing.
7) Can the FDB2125 be used on a 50 Hz system or on DC?
Both. Frequency rating is 50/60 Hz, so it works on export or 50 Hz equipment as well as standard North American 60 Hz. It also carries a 250 Vdc rating alongside the 600 Vac rating, which covers two-pole DC applications within that voltage.
How fast can I get the B-LINE FDB2125 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the
continental
U.S.
Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit,
reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the B-LINE FDB2125 come with a warranty?
Absolutely. The B-LINE FDB2125 is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the B-LINE FDB2125?
You can call, text, or email our expert support team for fast answers. We’re here to help with
product
selection,
installation tips, and troubleshooting. Contact Us
Why buy the B-LINE FDB2125 from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support,
and
rewards on
every order.
Our team is always ready to help you choose the right product for your project.