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Manufacturer Resources
Product Specs
- Frame Size:
- L-,M-frame
- Series:
- Series G
- Special Features:
- Pigtail leads
- Used With:
- L-frame HMCP and M-frame breakers
- Voltage Rating:
- 24 Vdc
- Department:
- Electrical
- Product Group:
- Mounting Hardware
- Product Subgroup:
- Mounting Accessories
- Product Type:
- Field mounted undervoltage release mechanism
- Product Length:
- 5.5 IN
- Product Details:
- Field mounted undervoltage release mechanism
- Mounting Method:
- Left
- Product Height:
- 3 IN
- Product Weight:
- .6 LB
- Product Width:
- 2.38 IN
B-LINE UVH4LP21K – Frequently Asked Questions
1) Which Eaton breaker frames does the UVH4LP21K undervoltage release fit?
The UVH4LP21K is built for Eaton L-frame and M-frame molded case breakers, specifically L-frame HMCP units and M-frame breakers. If your breaker is a different frame class (F-frame, J-frame, N-frame), this accessory is not the right release for it.
2) Can this undervoltage release be added to a breaker already installed, or does it have to be factory fitted?
It is a field mounted undervoltage release mechanism, so an electrician can install it into a compatible L- or M-frame Eaton breaker in the field rather than ordering a new factory-assembled breaker. The breaker has to be de-energized and removed from service to fit it.
3) Does the UVH4LP21K mount on the left or right side pocket of the breaker?
Left. The mounting method for the UVH4LP21K is the left accessory pocket, so if that pocket is already occupied by a shunt trip or auxiliary switch on your breaker, you will need to plan the accessory layout around it.
4) How is the coil wired in, and are leads supplied?
The release comes with pigtail leads, so the control wiring terminates by splicing or landing those leads rather than at a terminal block on the device. Route them out of the breaker to your 24 Vdc control source.
5) What is the difference between an undervoltage release and a shunt trip on a molded case breaker?
An undervoltage release, like the UVH4LP21K, trips the breaker when its control voltage drops away or is lost. A shunt trip does the opposite: it needs voltage applied to trip. Pick the undervoltage release when loss of a control signal or supply must open the breaker (interlocks, emergency stop loops, fail-safe shutdown); pick a shunt trip when a remote signal has to actively command the trip.
6) Where do I find the installation instructions for the UVH4LP21K?
Eaton publishes a spec sheet for the UVH4LP21K undervoltage release, linked from the product information, which covers the Series C molded case breaker application. Use it alongside the breaker's own accessory installation sheet, since the release fits the left accessory pocket.
How fast can I get the B-LINE UVH4LP21K 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 UVH4LP21K come with a warranty?
Absolutely. The B-LINE UVH4LP21K 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 UVH4LP21K?
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selection,
installation tips, and troubleshooting. Contact Us
Why buy the B-LINE UVH4LP21K from ZenSupply?
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and
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every order.
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