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Manufacturer Resources
Spec Sheet
Product Specs
- Amperage Rating:
- 125A
- Frame Size:
- K-frame
- Number Of Poles:
- Three-pole
- Series:
- Series C
- Trip Type:
- Thermal magnetic
- Department:
- Electrical
- Product Length:
- 7 IN
- Product Height:
- 5.3 IN
- Product Weight:
- 1.8 LB
- Product Width:
- 4.2 IN
B-LINE KT3125T – Frequently Asked Questions
1) What amperage and pole configuration is the Eaton Series C KT3125T trip unit?
The KT3125T is a 125 amp, three-pole trip unit for K-frame molded case breakers in the Eaton Series C line. If your panel schedule calls for a three-pole 125A K-frame device, this is the matching rating.
2) Will the KT3125T fit a J-frame or F-frame Eaton breaker?
No. The KT3125T is built for the K-frame size only. Frame size is not interchangeable across Eaton molded case breaker families, so an F-frame or J-frame opening needs the trip unit built for that frame. Confirm the frame letter stamped on the breaker before ordering.
3) Is the KT3125T trip unit thermal magnetic or purely electronic?
Trip type on the KT3125T is thermal magnetic. That means it uses a bimetal element for overload and a magnetic element for short circuit, rather than a solid state sensing package with adjustable long time and short time bands. If your spec calls for adjustable electronic trip settings, a thermal magnetic unit will not give you them.
4) How much space does the KT3125T take up, and how heavy is it to handle overhead?
Dimensions are 7 x 5.3 x 4.2 inches and the unit weighs 1.8 lb. Light enough for a one-hand install in a panel, but check your available gutter and cover clearance against the 7 inch length before you commit the enclosure layout.
5) I need to order a replacement trip unit for an Eaton Series C breaker. What part number do I give my distributor?
The manufacturer part number is KT3125T, Eaton Series C. That number alone identifies the 125A three-pole K-frame thermal magnetic trip unit, so it is all a distributor needs to pull the right item.
6) Can I use the KT3125T to change the amp rating on an existing K-frame breaker?
The KT3125T sets the device at 125 amps. Swapping a trip unit changes the breaker's rating, so the new rating has to agree with the conductor sizing and the panel schedule for that circuit. Do not drop a 125A unit onto a circuit whose wire was sized for a lower trip.
7) Where can I get the full electrical data for the KT3125T for my submittal package?
Eaton publishes a spec sheet for the KT3125T, and it is linked directly from the product information. That document is what you attach to a submittal when the engineer wants interrupting ratings and trip curve data on the K-frame 125A unit.
How fast can I get the B-LINE KT3125T 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 KT3125T come with a warranty?
Absolutely. The B-LINE KT3125T 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 KT3125T?
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 KT3125T from ZenSupply?
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and
rewards on
every order.
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