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Siemens HED42B040L Molded Case Circuit Breaker
- 40A
- 2 Pole
- Unit Mount
Siemens
HED42B040L
Molded Case Circuit Breaker
Brand
Siemens
SKU
HED42B040L
Quantity
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Siemens HED42B040L - 40A 2 Pole Molded Case Circuit Breaker
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Description
Built for standalone applications, this 40-amp unit-mount breaker delivers robust thermal-magnetic protection. It achieves a 42kA interrupting rating at 480VAC, making it suitable for demanding environments. Unlike bolt-on variants, this model fastens into individual enclosures, switchboards, and motor control centers. It comes equipped with LN1E100 line and load lugs, accepting 10 to 1/0 AWG wire. The non-interchangeable trip mechanism ensures consistent LI protection.Specifications
| Brand | Siemens |
|---|---|
| Part Number | HED42B040L |
| Series | HED4 |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 250VDC |
| Phase | 1 |
| AIC Rating | 100kA @ 240VAC, 42kA @ 480VAC, 30kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Enclosures, Switchboards, Motor Control Centers |
| Wire Gauge | 10 AWG - 1/0 AWG (Cu/Al) |
| Max Wire | 1/0 AWG |
| Min Wire | 10 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch, Padlock Attachment |
|---|---|
| Accessories | Line and Load Lugs (LN1E100) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, High Interrupting Capacity, Non-Interchangeable Trip, Quick-Make/Quick-Break, Trip-Free Mechanism, HID Rated |
Product FAQs
5 answersWhat types of panels or enclosures are compatible with the HED42B040L?
As a unit-mount, feed-thru breaker, the HED42B040L is designed for individual enclosures, switchboards, and motor control centers that accommodate Siemens ED-frame breakers. It does not plug or bolt into standard residential load centers.
What does the L suffix mean in the HED42B040L catalog number?
The L suffix indicates that the breaker is supplied with factory-installed line and load side lugs, specifically Siemens part number LN1E100.
Which replacement lugs are used on the HED42B040L circuit breaker?
This breaker uses Siemens LN1E100 aluminum lugs. These lugs accept a single 10 AWG to 1/0 AWG copper or aluminum conductor.
Can the HED42B040L be used in direct current applications?
Yes, this breaker is certified for use in DC electrical systems. It provides thermal-magnetic protection for circuits up to 250VDC.
Can the trip settings on the HED42B040L be adjusted during installation?
No, this breaker features a non-interchangeable trip unit. The thermal and magnetic trip points are factory set and cannot be modified in the field.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 13 reviews.
Total 5 star reviews: 13 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
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Rating
13 reviews
- PMPete M.Verified BuyerReviewingSiemens HED43B060 - 60A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/19/26Good price - Best website
Awesome price on an item. easy to use website made finding the right breaker and purchasing it super easy
- BCBrad C.Verified BuyerReviewingSiemens HED43B070 - 70A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars5/12/26Thank You
The breaker works perfectly, but I'm more impressed by the fast, prompt delivery. Will be using you again, thank you.
- MLMichael L.Verified BuyerReviewingSiemens HED43B020 - 20A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars4/15/26Siemens breaker
Return customer, always great service and quick delivery. A+++
- JMJonathan M.Verified BuyerReviewingSiemens HED43B030 - 30A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars2/10/26Breaker
Fast Delivery, just what I ordered !!
- RFRussell F.Verified BuyerReviewingSiemens HED41B040 - 40A 1 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars2/6/26Just what I ordered
Straight forward, simple process. On time delivery.