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Eaton MARK 75 Type HLA Molded Case Circuit Breaker Trip Unit, 600V, 250A
Model: EAT-HLA3250T
Eaton MARK 75 Type HLA Molded Case Circuit Breaker Trip Unit, 600V, 250AThe Eaton MARK 75 Type HLA Molded Case Circuit Breaker Trip Unit is engineered for installation into Eaton MARK 75 breaker...
Eaton
$7,661.54
Eaton MARK 75 Trip Unit for Molded Case Circuit Breakers
The Eaton MARK 75 Trip Unit is a genuine OEM aftermarket accessory engineered for Eaton molded case circuit breakers, designed as a direct renewal part for Frame J-K breaker bodies. Built for three-pole applications with a 600 V voltage rating and 800 A amperage rating, this trip unit delivers a magnetic trip range of 3000-6000 A for accurate, field-adjustable overcurrent protection. UL Listed for code-compliant performance, it is a reliable choice for life-extension and renewal-parts programs on existing Eaton switchgear.
Key Features
- Amperage Rating: 800 A rating supports the continuous current demands of three-pole molded case circuit breaker installations.
- Voltage Rating: 600 V rating makes this trip unit suitable for demanding commercial and industrial power distribution systems.
- Magnetic Trip Range: Adjustable 3000-6000 A magnetic trip range allows precise tuning of instantaneous overcurrent protection in the field.
- Frame Compatibility: Purpose-built for Frame J-K molded case circuit breakers, ensuring correct fit and function as a genuine renewal part.
- Number of Poles: Three-pole configuration matches standard 3-phase breaker bodies for straightforward replacement.
- Compact Footprint: Measures 5.5 in wide by 10.5 in in length/depth by 6.9 in in height, sized to fit within existing breaker enclosures.
- Genuine Eaton Type: Identified as a MARK 75 Trip unit, part of Eaton's aftermarket renewal parts and life-extension solutions lineup.
Certifications & Compliance
- UL Listed
Technical Specifications
- Product Type: Circuit Breaker
- Type: MARK 75 Trip unit
- Voltage Rating: 600 V
- Amperage Rating: 800 A
- Number of Poles: Three-pole
- Magnetic Trip Range: 3000-6000 A
- Frame Size: Frame J-K
- Product Width: 5.5 in
- Product Length/Depth: 10.5 in
- Product Height: 6.9 in
- Certifications: UL Listed
Typical Applications
- Molded Case Circuit Breaker Renewal and Life-Extension Programs
- Commercial and Industrial Power Distribution Systems
- Switchgear Maintenance and Retrofit Projects
- Frame J-K Breaker Servicing and Repair
- Aftermarket Replacement Parts Inventory for Eaton Switchgear
Why Eaton?
Eaton's MARK 75 Trip Unit is manufactured as a genuine renewal part, giving facility and maintenance teams confidence that replacement components match original equipment fit, form, and function. With a UL Listed rating, a defined 600 V/800 A rating, and a field-adjustable 3000-6000 A magnetic trip range, this trip unit supports code-compliant, reliable overcurrent protection for three-pole Frame J-K molded case circuit breakers. Choosing genuine Eaton aftermarket parts helps extend the service life of existing switchgear investments.
Manufacturer Resources
Product Specs
- Product Width:
- 5.5 in
- Magnetic trip range:
- 3000-6000 A
- Number of poles:
- Three-pole
- Amperage Rating:
- 800A
- Voltage Rating:
- 600V
- Product Length/Depth:
- 10.5 in
- Frame size:
- Frame J-K
- Compliances:
- Contact Manufacturer
- Product Height:
- 6.9 in
- Product Type:
- Trip Unit
- Certifications:
- UL Listed
- Department:
- Electrical
- Configuration:
- Three-Pole
- Listing:
- UL Listed
- Series:
- MARK 75
- Product Group:
- Wiring Devices
Eaton HMA3800T – Frequently Asked Questions
1) What are the voltage and amperage ratings on the Eaton MARK 75 800A trip unit?
Rated 600 V and 800 A. That covers standard 480Y/277 V and 600 V commercial and industrial distribution, and the 800 A continuous rating sets the breaker's current-carrying duty. Do not fit it to a breaker body rated for a different ampere frame.
2) Can the magnetic trip setting be adjusted in the field on the Eaton MARK 75 trip unit?
Yes. The instantaneous magnetic trip is adjustable from 3000 to 6000 A, so a maintenance electrician can tune the pickup on site to coordinate with downstream devices rather than swapping the unit for a different setting.
3) Do I replace the whole breaker or just the trip unit?
A trip unit swap is the cheaper path when the breaker body, contacts, and mechanism are still sound. The MARK 75 HMA3800T is sold as a renewal part for life-extension on existing Eaton Frame J-K gear, so you keep the installed breaker body and bus connections and replace only the sensing and tripping assembly. If the body itself is damaged or the ampere frame is wrong for the load, a trip unit will not fix that.
4) Is the ABB TJK J600 trip unit an equivalent replacement for an Eaton HMA3800T MARK 75 trip unit?
No. The Eaton HMA3800T is a MARK 75 series trip unit rated 800A at 600V, three-pole, built for Eaton Frame J-K molded case breaker bodies with an adjustable 3000-6000 A magnetic trip range. The ABB TJK is a J600 series 400A three-pole trip unit. The amperage ratings differ by half and the two are built to different manufacturers' breaker frames, so the ABB unit is not a drop-in for an Eaton Frame J-K body. If you are renewing an Eaton breaker, stay with the MARK 75 HMA3800T.
5) I need a 400A three-pole trip unit, not 800A - what should I look at instead of the HMA3800T?
The Eaton HMA3800T MARK 75 is rated 800A and will not suit a 400A application. For a 400A three-pole trip unit, the ABB TJK J600 is rated 400A in a three-pole configuration. Confirm the breaker body you are servicing is the matching ABB J600 frame, since trip units are frame-specific renewal parts - the Eaton unit is built for Eaton Frame J-K bodies.
6) Is the Eaton MARK 75 trip unit UL Listed for code work in a commercial facility?
UL Listed, yes. For a facility or MRO buyer standardizing on genuine Eaton renewal parts across switchgear, that listing is stated on the part itself.
7) How much room does the Eaton MARK 75 trip unit need inside the enclosure?
The unit measures 5.5 in wide, 10.5 in in length/depth, and 6.9 in high. Since it is a renewal part for an existing Frame J-K breaker body, it is sized to the original footprint, but those numbers let you confirm clearance if the gear has been modified or re-barriered.
8) What else could I use instead of the Eaton MARK 75 800A trip unit?
For a different frame and rating, ZenSupply carries the ABB TJK J600 400A 3-Pole Trip Unit, an ABB J600 series part. It is not a substitute on Eaton gear, though. Trip units are frame-specific, so an ABB J600 unit goes in ABB J600 breakers and the Eaton MARK 75 goes in Eaton Frame J-K bodies. Pick by the breaker you already have in the switchboard.
9) Is the Eaton HMA3800T a genuine Eaton part number or an aftermarket copy?
HMA3800T is the Eaton catalog number for the MARK 75 trip unit, supplied as a genuine Eaton renewal part rather than a third-party equivalent. Distributors quoting against an OEM spec can cite it directly.
How fast can I get the Eaton HMA3800T delivered?
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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 Eaton HMA3800T come with a warranty?
Absolutely. The Eaton HMA3800T is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
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