General Electric produced a line of medium voltage air circuit breakers called the MAGNE- BLAST for over 30 years. The product line was very popular and was produced in a wide range of sizes and ratings to meet customer’s needs.

Particular attention needs to be paid to several parts of the nameplate when you’re looking for replacement MAGNE-BLAST breakers or parts for these GE circuit breakers. This flow chart was designed to streamline the specification process and help you identify your MAGNE-BLAST designation.

Even with the flowchart, it can still be easy to miss specifics for designation There will be additional information you will need. Rated Amps, close and trip voltage, and mech type can all be found on the nameplate. When in doubt, a photo of the nameplate and a photo of the breaker from the front will give your supplier a clear understanding of what you need. The following photos of MAGNE-BLAST nameplates show how important details like the letter suffixes are in determining exactly what you need.

Still confused? Contact us today or try our Mobile Ap- NPE on the Go  and we’ll help your figure it out. As a circuit breaker supplier, that’s what we’re here for.

Finding old or obsolete General Electric circuit breakers can be challenging. GE has produced circuit breakers for over 70 years, which can make it difficult to match the right models and model numbers to your needs. In this article, we’ll present a brief history of GE’s circuit breaker production and help you understand how to identify what circuit breaker you’re looking for.

A Brief History of General Electric Circuit Breakers

GE’s “Slate back” line of type AE and AL air circuit breakers was its first product line utilizing one of the first true inverse time elements to obtain automatic “resettable” overcurrent protection. This line marked a huge step up from simple fused protection. Sometime later, technological improvements prompted a redesign. GE iresponded by ntroducing the AK line of breakers. These models featured improved electro-mechanical trip units and were designed to fit both AKD and AKD5 switchgear.

In the 1980’s, GE redesigned the AK line and gave the product line the AKR prefix. Although they may initially seem similar in appearance to the older style, the AKRdesign has been improved and is not interchangeable with previous versions. This product line was designed to fit both AKD6 and the later redesigned AKD8 switchgear.

As products and technology continue to evolve through the Wavepro and AKD 10 up through and including Entelliguard and AKD 20 switchgear. These changes make it very important for users to be able to read breaker numbers to identify which type of breaker model they need.

How to Read a General Electric Breaker Number

Almost all the digits in an AK or AKR model number identify important characteristics of the breaker. It is important to either understand these details or be able to relay that information so that your supplier does.

When it comes to reading and understanding an AK or AKR breaker number, let’s start by using an AK-25 circuit breaker as an example. At a glance, with the door closed, most AK-25’s look the same, but the missing digits between the AK and 25 reveal important information that is needed to assure a safe and proper fit. You can use these quick guidelines to identify the specific model of a General Electric circuit breaker:

4 Steps to Identifying GE Circuit Breaker Model

1. The first part, “AK”, tells you the general designation of one of two switchgear vintages that the breaker will fit in - AKD or type AKD 5.
2. The last part, “25”, indicates one of the smaller feeder breakers that is rated 600 amp AC continuous and has a frame rating of 25,000 amps interrupt (AC). 
3. There are up to 4 more spaces for letters or numbers between the AK and 25 that are important.
   1. One could be a “U” which would indicate the addition of current limiting fuses.
   2. Another could be an “F” which designates a special field discharge option.
   3. There will be a number, most likely a 2 but it could be a 3, 4, all the way up to 10, which designates which type of trip unit that was installed at the factory.
   4. After the 2 or other trip unit number there could be an “A”. Absence of an “A” indicates that it is for AKD switchgear, the presence of it indicates it is for type AKD5 switchgear.
4. For more information on how to understand what each letter or digit of the model number means, we’ve developed a guide. This guide will help you identify most of the options built into your breaker from the factory and which, if any, will need to be changed or upgraded.

Other Questions to Ask When Identifying Type AK and AKR GE Circuit Breakers

In addition to knowing the brand and product number you’re looking for, here are some other questions to help identify the perfect solution for your needs:

• Is the breaker A. electrically or B. manually operated?
• If A, what is the voltage of the close coil, control relay and trip coil?
• If A, do you have a wiring diagram number? 
• Why type of trip unit is needed?
• What trip function is required?
• Are any accessories like bell alarm or under voltage protection required?

To download this chart click here: flowchart for AK and AKR circuit breakers  If you’re still having trouble or are unsure of what you need, just let us know and we’ll be happy to walk you through the process.

NPE's staff has been specifying breakers, parts and accesories for over 40 yrs. 

Our hands on experience starts with current production equipment and goes back to equipment dated in the 1940's!

- Get more information than you think you'll need. Details matter!

- Photo's really are worth 1000 words! From the front, back, bottom they all help!

- Nameplates help but rarely have enough information and serial numbers are rarely helpful. 

- When in doubt go to our mobile ap NPE on the Go.  We'll walk you through the details and give you a place to attach some picture!

Find a Circuit Breaker Supplier That Asks the Right Questions

We realize we ask a lot of questions that's because we want you to get the right stuff- the first time

Just think what you might be getting from somone who doesn't ask these questions!

When you have questions about your circuit breakers, contact us today. If we can’t help you with your specific problem, we’ll tell you and direct you to someone who can. That’s what we are here for.