Siemens NGB3K020B Molded Case Circuit Breaker
- 20A
- 3 Pole
- Bolt-On
Siemens
NGB3K020B
Molded Case Circuit Breaker
Brand
Siemens
SKU
NGB3K020B
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Siemens NGB3K020B - 20A 3 Pole Molded Case Circuit Breaker
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Description
Engineered for commercial distribution, the Siemens NGB3K020B is a 3-pole, 20A molded case circuit breaker. It features fixed thermal-magnetic trip units for dependable long-time and instantaneous protection. This bolt-on breaker installs into Siemens P1 through P5 panelboards. It is superseded by the 3VA5120-4ED31-0AA0 when using the required mounting kit. Rated 100kA at 240V and 25kA at 480Y/277V, it handles demanding fault currents and supports reverse feed applications.Specifications
| Brand | Siemens |
|---|---|
| Series | NGB |
| Amperage | 20A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 240VAC, 480Y/277VAC, 600Y/347VAC, 125/250VDC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 25kA @ 480Y/277VAC, 14kA @ 600Y/347VAC, 14kA @ 125/250VDC |
| Frame Type | GB2 |
|---|---|
| Terminal Type | Lugs |
| For Use With | Siemens P1, P2, P3, P4, P5 Panelboards |
| Wire Gauge | 14-6 AWG (Cu), 12-6 AWG (Al) |
| Max Wire | 6 AWG |
| Min Wire | 14 AWG (Cu), 12 AWG (Al) |
| 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, Alarm Switch |
|---|---|
| Accessories | Load Side Lugs |
| Standards | CSA C22.2 No. 5, UL 489, NEMA AB 1 |
| Approval | CSA, HACR, HID, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Reverse Feed |
Product FAQs
6 answersWhich Siemens panelboards accept the NGB3K020B circuit breaker?
This breaker is engineered specifically for Siemens P1, P2, P3, P4, and P5 panelboards. It mounts directly to the internal busbars using a bolt-on connection.
What does the GB2 frame designation mean for this breaker?
The GB2 designation indicates that this breaker belongs to the Siemens Sentron GB/GG frame family. This defines its physical footprint and ensures compatibility with specific Siemens panelboard mounting kits and internal accessories.
What wire sizes are accepted by the standard lugs on the NGB3K020B?
The factory-installed lugs accept 14 to 6 AWG copper (Cu) wire or 12 to 6 AWG aluminum (Al) wire. Ensure all conductors are properly sized according to the 20A rating and local electrical codes.
Does the NGB3K020B require a specific mounting kit for installation?
When installing this breaker into compatible Siemens P1 through P5 panelboards, it bolts directly to the bus. However, depending on the specific panelboard generation and existing setup, a dedicated branch mounting kit or barrier may be required. Always consult the panelboard wiring diagram before installation.
What type of protection does the LI trip function provide on the NGB3K020B?
The LI designation stands for Long-Time and Instantaneous trip functions. This fixed thermal-magnetic trip unit protects commercial and industrial branch circuits against sustained overloads and sudden short circuits.
Can the NGB3K020B be used in direct current (DC) applications?
Yes, this breaker is rated for use in DC systems up to 125/250V DC, where it provides an interrupting capacity of 14kAIC. This makes it suitable for specific industrial control or backup power applications.
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Reviews
Review summary
Customers rate this product 4.5 out of 5 based on 8 reviews.
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Rating
8 reviews
- JHJohn H.Verified BuyerReviewingSiemens NGB3B015B - 15A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/16/26480v breakers
The breakers work great
- BPBland P.Verified BuyerReviewingSiemens NGB3B100 - 100A 3 Pole Molded Case Circuit BreakerI do not recommend this productRated 1 out of 5 stars7/22/26NO LUGS!!
I ordered this breaker and it arrived with no lugs. It was advertised as new so we didn't open the box and check until the shutdown we needed it for. When we discovered the lugs were missing we sent an email requesting a set overnighted. We didn't get a response for a couple of days, at which point we had already ordered lugs from their competitor Simply Breakers. They asked for pictures and questioned weather we had ordered the correct breaker asking if we needed lugs on both sides. This is a panel breaker and their is only one configuration that I am aware of which is bolted to bus in panel and wires to the three lugs on the other side. I have never had to order lugs separately for this style of breaker. They asked for pictures of box and what was in it, of course at this point the breaker is already installed and the box is thrown away. I sent a receipt for the overnight lugs from Simply breakers and asked for whatever credit they could provide. I received crickets to date. I have never had a problem with an order in the past from super breakers, but they are to busy to even respond to my request so I will think twice before I order anything from them again. It will be my last option once all others have been exhausted. Use Simply Breakers they have better stock and service.
- PFPaul F.Verified BuyerReviewingSiemens NGB3B060B - 60A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/24/26Great service, quick shippin
Need I say more.I have used SB. When we need it and need it quickly Always have what I need.
- BPBJ P.Verified BuyerReviewingSiemens NGB3B020B - 20A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars5/11/26NGB3B020B
I recently purchased the NGB3B020B and I’m very satisfied with the quality and performance. The breaker feels solid and well-made, and installation was straightforward. It works exactly as expected and provides reliable protection for my electrical setup. Shipping was fast and the product arrived in excellent condition. I would definitely purchase from this seller again.
- RSRadovan S.Verified BuyerReviewingSiemens NGB3B050B - 50A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars3/9/26Absolutely amazing service.
On Time