Identifying MAGNE-BLAST Circuit Breaker Designations

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.

Image of a designation flowchart for MAGNE-BLAST circuit breakers.

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.

First nameplate image from a MAGNE-BLAST circuit breaker.
Second nameplate image from a MAGNE-BLAST circuit breaker.

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.

How to Find and Identify Old or Obsolete GE (General Electric) Circuit Breakers Type AK and AKR

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.

Image of a General Electric circuit breaker.

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 marked a huge step up from simple fused protection. Sometime later, technological improvements prompted a redesign so GE introduced 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 design 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.

How to Read a General Electric Breaker Number

Almost all of the digits in an AK or AKR model number identify important characteristics of the breaker. It is important to either understand these details or even more important make sure your supplier does. Let’s use 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:

  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. One could be a “U” which would indicate the addition of current limiting fuses. Another could be an “F” which designates a special field discharge option. 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. 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 in to your breaker from the factory and which, if any, will need to be changed or upgraded.



Other Questions to Ask

In addition to knowing the brand and product number you’re looking for, here are some other questions to help us 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  Isf 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.


How to Streamline the Process of Identifying Obsolete Circuit Breakers and Components

When there is a problem with a circuit breaker or piece of switchgear, you need to be able to communicate exactly what you need to a vendor so that you can get the right equipment the first time and at the right price. Time is often the most critical element to shorten outages and restore power and production.

Our experts have worked with circuit breakers since 1983 and we can tell you from experience that while technology has improved this process immensely, it still has its pitfalls. The bottom line is that if the equipment is not specified correctly, it may not fit or work and can even become dangerous.

Image of an expert at a circuit breaker supplier.

Have Plenty of Information About Your Circuit Breaker

The best way to identify and communicate with a circuit breaker supplier is to get more information than you think will be needed. The model number of a circuit breaker is a start, but may not cover all the details. Serial numbers are rarely traceable. When they are, it may take weeks for the factory to reply.

Photos of the nameplate can help, but again, it may or may not detail all that is needed.

A good way to ensure that your getting the right info is with our mobile ap NPE on the GO. In this ap, we walk you through all the questions we would ask you for on the phone, and ask you to take a couple of pictures too. 

We like to take an “all of the above” attitude. We find that when we know the breaker’s model number and have clear photographs of all the nameplates (may be more than one), along with photos of the front, back, and sides and/or photos of the parts in question. We can quickly and accurately assess the situation and provide the most cost-effective solution to solve the issue at hand.

In the real world, however, this is often not possible. It’s common that information is handed up or down the chain of command and details can be lost or simply not communicated in the first place. This can and will necessitate someone going back to get the needed information, which can be both time consuming and frustrating.

Find a Circuit Breaker Supplier That Asks the Right Questions

When inquiring to multiple vendors, one or several of the vendors will typically not ask as many questions and may seem to have a quick and easy answer. The question that should then be asked is, “Why aren’t they asking the questions?” and “Will the equipment they ship work?”

If this seems like a daunting task, it is, or it can be without the help of a qualified vendor who is familiar with the equipment and can walk you through the pitfalls to get you the right equipment at the right time, for the right price.

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.

Where to Find Old, Discontinued, or Refurbished Circuit Breakers from General Electric, Westinghouse, Allis Chalmers, and More

* Over 75%* of Switchgear running commercial and inustrial facilities is over twenty years old

* Original equipment manufacturers consider many of these obsolete and no longer support them with new components yet the with         proper maintanance will remain reliable for many years to come.

* Used equipment dealers are your source for equipment and solutions to stay up and running:

     ** Safely

     ** Reliably

     ** Economically

National Power Equipment Inc's (NPE) warehouses are filled with thousands of circuit breakers and switchgear cabinets, and tens of thousands of parts. These product lines date all the way back to World War II, and its staff is well versed in specifying equipment for them.

National Power Equipment’s “Class One” process of reconditioning equipment brings equipment back to “like new” condition. The process includes:

  • Breaker disassembled to its smallest components and inspected for wear and damage
  • Parts re-plated, stripped, and painted or buffed and polished to “like new” condition
  • Breaker reassembled with new wiring and upgrades and testing to industry standard

Image of a circuit breaker for sale.

Circuit Breakers

NPE warehouses a wide variety of old, obsolete, re-manufactured, and refurbished circuit breakers, specializing in low voltage (600 Volt AC or less) through medium voltage (15KV) circuit breakers, switchgear, and parts. Our inventory includes equipment from the following circuit breaker brands:

Parts  Parts  Parts

In order to maintain your equipment, your going to need access to parts!  

These parts can include relays, transformers, trip devices, fuses, and switchgear and don't forget aftermarket parts store!

Hard-to-Find Circuit Breakers

If you’re unsure where to look for an older or obsolete circuit breaker, start with our circuit breaker equipment search or our mobile ap NPE on the GO to see if the product you’re looking for is in our inventory. If you can’t find what you’re looking for, there’s a good chance we know how to help. Contact us for those hard to find circuit breakers or equipment, and we’ll be happy to navigate you in the right direction. 

At NPE our motto is always, " The right equipment, at the right price- right now!"


*Based on informal survey of customers 1994-1996