B-Line Eaton accessory trip ...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$422.38
B-Line Eaton accessory trip unit, Trip unit, 400 A, Frame J-K, Series C

B-Line Eaton accessory trip unit, Trip unit, 400 A, Frame J-K, Series C

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Model: 4KS350T
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In Stock (leaves warehouse same day if ordered before 3pm ET)

$422.38
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Eaton molded case circuit breaker accessory trip unit, Trip unit, 400 A, Frame J-K, Series C

Manufacturer Resources

Product Specs

Amperage Rating:
400A
Compliances:
Contact Manufacturer
Frame Size:
Frame J-K
Product Height:
1.5 in
Product Length Depth:
2.3 in
Product Weight:
.1 lb
Product Width:
1.5 in
Series:
Series C
Department:
Electrical
Product Type:
Trip unit
Product Details:
Trip unit

B-LINE 4KS350T – Frequently Asked Questions

1) What breakers does the Eaton 4KS350T trip unit fit?
The 4KS350T is an Eaton Series C molded case circuit breaker trip unit for J and K frame breakers, rated 400 A. It is a frame-specific part, so it goes into a J or K frame Series C breaker and nothing else. If your breaker is a different frame size or a different series, this unit is the wrong part.
2) Can I use the 4KS350T to change the amp rating of my Eaton J or K frame breaker?
Yes, that is what an interchangeable trip unit does. The 4KS350T sets a J or K frame Series C breaker at 400 A. If you need the breaker to run at a different ampere rating, you order the trip unit in that rating instead, not this one.
3) What part number do I order for a 400 A Eaton Series C J-K frame trip unit?
Order Eaton part number 4KS350T. That is the single catalog number covering the 400 A rating for Series C J and K frame breakers, so there are no finish, voltage, or size options to specify with it.
4) I have a spare Eaton J frame breaker rated at a different amperage. Can I bring it up to 400 A?
If it is a Series C J or K frame breaker with an interchangeable trip unit, fitting the 4KS350T rates that breaker at 400 A. What you cannot do is exceed the frame's own ampere capacity, so confirm the frame is rated to carry 400 A before swapping. Series and frame have to match: a Series C J-K unit will not go into another Eaton series.
5) How much space does the 4KS350T trip unit take up inside the breaker?
It measures 2.3 x 1.5 x 1.5 inches and weighs about a tenth of a pound. It seats inside the breaker case rather than adding to the envelope, so panel and enclosure clearances are governed by the J or K frame breaker it goes into.
How fast can I get the B-LINE 4KS350T 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 4KS350T come with a warranty?
Absolutely. The B-LINE 4KS350T 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 4KS350T?
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 4KS350T from ZenSupply?
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