Eaton / Westinghouse KB3070 Molded Case Circuit Breaker
- 70A
- 3 Pole
- Unit Mount
Quantity
Eaton / Westinghouse KB3070 - 70A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
Belonging to the proven Series C family, this 70-amp, 3-pole molded case circuit breaker delivers reliable long-time and instantaneous protection. It is built for demanding commercial and industrial environments. The unit mount configuration fits seamlessly into legacy Westinghouse panelboards, motor control centers, and Eaton enclosures. For modern upgrades, this K-frame model is replaced by the KD3070. Featuring a 25kA interrupting capacity at 240VAC, it provides flexible defense.Specifications
| Brand | Eaton / Westinghouse |
|---|---|
| Series | KB |
| Amperage | 70A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 25kA @ 240VAC, 22kA @ 480VAC, 14kA @ 600VAC, 10kA @ 250VDC |
| Frame Type | KB |
|---|---|
| Terminal Type | Lugs |
| For Use With | Westinghouse Panelboards, Switchboards, Motor Control Centers, Eaton Series C Panelboards |
| Wire Gauge | 4 AWG - 350 kcmil (Cu/Al) |
| Max Wire | 350 kcmil |
| Min Wire | 4 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, NEMA AB-1, UL 489, W-C-375b |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Interchangeable Trip |
Product FAQs
5 answersWhat enclosures and panelboards accept the KB3070?
This bolt-on K-frame breaker is compatible with legacy Westinghouse and Cutler-Hammer panelboards, switchboards, and motor control centers. It is also compatible with modern Eaton Series C panelboards that are configured for K-frame breakers.
How does the adjustable magnetic trip on the KB3070 benefit my electrical system?
While the thermal overload protection is fixed, the adjustable magnetic element allows you to set the instantaneous short-circuit pickup level. This flexibility helps electricians coordinate the breaker with downstream devices and prevents nuisance tripping from temporary surges, such as motor starting inrush currents.
Which lug kit is typically used with the KB3070?
The standard lug kit for this K-frame breaker is the TA250KB, which accepts 4 AWG to 350 kcmil copper or aluminum wire. Always verify the lug kit installed matches your conductor material and size requirements before terminating.
Is the Westinghouse KB3070 still manufactured?
The KB3070 is a legacy K-frame breaker originally produced by Westinghouse and Cutler-Hammer. It is now supported under the Eaton Series C family. If a new replacement is required, Eaton KD-frame breakers (such as the KD3070) are often used as modern equivalents, though terminal spacers like the TAD3 may be required depending on the panelboard mounting configuration.
What safety precautions apply when installing the KB3070?
Always de-energize the panelboard or switchboard before installation. Verify that the available fault current at the installation point does not exceed the breaker interrupting rating, and ensure all bolt-on connections are properly torqued to maintain a secure, low-resistance connection.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 3 reviews.
- DHDavid H.ReviewingEaton / Cutler-Hammer KB3100 - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars4/21/23very easy to order and
very easy to order and received order promptly
- KLKelsee L.ReviewingEaton / Cutler-Hammer KB3250 - 250A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars5/29/21Excellent
Excellent
- BSBill S.ReviewingEaton / Cutler-Hammer KB3200 - 200A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/26/19electrical contractor
no hassle, good product that has been recertified. very satisfied with the result!