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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:
- Three-pole
- Series:
- Series C
- Terminals:
- Line and load
- Trip Type:
- Fixed thermal, fixed magnetic
- Voltage Rating:
- 600 Vac, 250 Vdc
- Department:
- Electrical
- Product Length:
- 7.4 IN
- Product Height:
- 4.9 IN
- Product Weight:
- 4.35 LB
- Product Width:
- 5 IN
B-LINE FDB3125L – Frequently Asked Questions
1) What interrupting rating does the Eaton FDB3125L breaker have at 240V and 480V?
The FDB3125L is rated 18 kAIC at 240 Vac and 14 kAIC at 480 Vac. If your panel's available fault current exceeds those numbers, this FDB frame won't satisfy the series or standalone rating you need and you'll have to move to a higher-interrupting F-frame breaker. Voltage rating on the device itself is 600 Vac / 250 Vdc, at 50/60 Hz.
2) Is the FDB3125L a three-pole 125 amp breaker?
Yes, three-pole and 125 amps, on the Eaton Series C F-frame. Trip unit is fixed thermal, fixed magnetic, so there are no adjustment dials to set in the field, and the trip is factory matched to the 125A rating.
3) Does the FDB3125L come with lugs, or do I have to order terminals separately?
Line and load terminals are included on the FDB3125L, so it lands out of the box without a separate lug kit. It also ships as a complete breaker rather than a frame-only assembly, which means the trip unit is already installed and matched.
4) Can I use the FDB3125L on a 600 volt three-phase system?
The device carries a 600 Vac rating, but the published interrupting ratings stop at 480 Vac (14 kAIC). Above 480 you need to confirm an interrupting rating for the voltage you're applying, because a voltage rating alone is not an application rating. For 240 Vac work the breaker gives you 18 kAIC.
5) What is the difference between a complete breaker and a frame-only FDB breaker?
A complete breaker arrives assembled and ready to install with its trip unit and terminals in place, which is what the FDB3125L is. A frame-only or breaker-frame item is sold without the trip unit so it can be paired with a separately ordered rating plug or trip assembly. If you want a fixed 125A three-pole device and nothing else to specify, the complete version is the one to buy.
6) How much space do I need in the enclosure for the FDB3125L?
Plan for a device measuring 7.4 x 5 x 4.9 inches (length, width, height as published) and weighing 4.35 lb. That footprint is what you check against the gutter space and door clearance in a retrofit enclosure before you commit, along with the wire bending space your lug size demands.
7) What is the exact part number to order this Eaton F-frame 125A breaker?
Order by manufacturer part number FDB3125L. The FDB prefix is the breaker type, the 3 is three poles, 125 is the amp rating, and it sits in Eaton's Series C F-frame line.
8) Will the FDB3125L work on a DC application?
It carries a 250 Vdc rating alongside the 600 Vac rating, so DC use up to 250 volts is within the device rating. Frequency rating is 50/60 Hz for AC service.
How fast can I get the B-LINE FDB3125L 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 FDB3125L come with a warranty?
Absolutely. The B-LINE FDB3125L 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 FDB3125L?
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installation tips, and troubleshooting. Contact Us
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