General Electric AKR Circuit Breaker Nomenclature

Why can’t we just quote all possible options on an AKR-30?  We get that question a lot.  General Electric type AKR circuit breakers came in hundreds of configurations.   Oftentimes different AKR breakers will interchange with the only differences between different model numbers being the type of trip unit.  Other times, model numbers that appear to be close to identical correspond to drastically different frames.

Similar to AK circuit breakers, AKR breaker model numbers are set up as groupings of numbers and letters separated by dashes.  Here is a description of the different number and letter designations.  A table follows at the bottom of this article to serve as an overview.

AKR  -  6D   - 30H

AKR is the breaker type indicating that is a later model GE Low Voltage Power Circuit Breaker

The “6” in AKR-6D-30H refers to the type of trip unit on the breaker. Specifically in this case the “6“ refers to GE VersaTrip.   The list of trip types is listed in the table at the end of this article.

The “D” in AKR-6D-30H refers to the switchgear type that the breaker is made for (in this case for AKD-8 switchgear).  Different switchgear types utilized different rack-in styles and also different primary disconnect orientations and styles  The earliest AKR breakers were designed for type AKD-6 switchgear and their letter designation was “A”.   Later model AKR breakers were designed for type AKD-8 switchgear and were designated by the letter “D“.  Breakers designated for AKD-6 and AKD-8 switchgear are not interchangeable although many parts between the two are identical.  In general “A” breakers had shallow front covers (escutcheons) that were painted blue.  “D” vintage breakers had deep escutcheons that were painted black.  In addition to the “A” and “D” vintages, you can also see breakers with the letter “B” such as an AKR-5B-30.  Breakers with the “B” designation were sold with OEM cradle assemblies for non-OEM switchgear builders to use in their own enclosures.  In this case, you need to inspect the breaker to identify what type of switchgear the breaker is designed for because “B” breakers can have either shallow or deep escutcheons.  In addition, “B” vintage breakers can have rear primary disconnects that are of a different orientation than their matching “A” or “D” vintage units.  Similarly, in AKR-75 and AKR-100 breakers the designations of “C” and “F” are used to indicate the breakers were used in gear that wasn’t built by General Electric.  

The “30” in our AKR-6D-30H example refers to the interrupting capacity of the breaker and also to the breaker frame size.   In this case, the “30” tells us that the breaker has an 800 Amp max frame.  The “30” typically refers to the breaker having the capacity to interrupt 30,000 amps at 480 volt BUT in this case since it is followed by the letter “H” the interrupting capacity for this breaker is increased to 42000 amp at 480VAC.

There are numerous exceptions to the generalized rules above, most of which are easier to understand in the table below.  A few explanations of some of the more common breaker styles:

* AKRT:  Refers to an AKR-50 breaker that is rated for 2000Amp (instead of 1600Amp). 

*AKR-5A-50H: Refers to AKR breaker with a higher interrupting capacity than non-”H” units.

*AKRU:  Refers to a breaker with integrated current limiting fuses, AKRU-30 or AKRU-50.  If working with an AKRU-75 or AKRU-100 the fuses are mounted in a separate drawout fuse truck used in conjunction with a standard AKR-75 or AKR-100 breaker equipped with an anti single phase device.

*AKR-30S:  Refers to a Substructure breaker. AKR-30S breakers are considerably smaller than their AKR-30 counterparts.  Actually AKR-30S breakers are built on frames similar to the original AK-2A-25 breaker.

* AKR-30L:  Indicates breaker is extra high interrupt

* AKR-100E:  Indicates extra high interrupt

* AKR-5AE-30:  Utilized in large substations to identify a specific breaker that can be interchanged IN THAT SUBSTATION with other “E” breakers.  Once the breaker is being resold the “E” designation is not important for determining interchangeability.

* AKJ:  Indicates a replacement AKR-50 that will fit in cubicle originally equipped for AK-50

* AKS:  Indicates a replacement AKR-50 that will fit in cubicle originally equipped for AK-50

Here is the chart that I promised that puts all of this together:

AKR

<1>

-

<2>

<3>

-

<4>

<5>

-

<6>

The numbers above refer to all of the different styles that I spoke about in this article

<1> - Indicates whether the breaker is anything but a standard AK.

·         AKRU: Fused breaker

·         AKRT: Designates that it is a 2000A frame AK-50

·         AKRL: AKR breaker designed to replace AL-2-50 breaker

<2> - Indicates what trip unit was originally installed on the breaker

·         AKR-2: EC trip unit  - typically ONLY  on DC breakers

·         AKR-4: ECS solid state trip unit

·         AKR-5: SST solid state trip unit

·         AKR-6: Versatrip solid state trip unit

·         AKR-7: MicroVersaTrip RMS-9 solid state trip unit

·         AKR-8: MicroVersaTrip EPIC trip unit (designed to use with the EPIC monitoring system)

·         AKR-9: MicroVersaTrip PLUS or PM solid state trip unit

·         AKR-10: MicroVersaTrip PLUS or PM solid state trip unit

<3> Refers to the type of switchgear the breaker is designed for.

• A:  AKD-6 switchgear
• D: AKD-8 switchgear
• B:  Indicates Non-OEM breaker, AKR-30 and AKR-50 only.  Could rack into AKD-6 or AKD-8.  Caution should be taken to inspect escutcheon and finger clusters when interchanging. 
• C:  Indicates Non-OEM breaker, AKR-75 and AKR-100 only.  Typically for AKD-6 gear although it is important to note that AKR-5C-100 breakers will not replace AKR-5A-100 breakers due to differences in width.
• F: Indicates Non-OEM breaker, AKR-75 and AKR-100 only.   Typically utilized in AKD-8 gear but caution should always be used in interchanging.

<4>  Refers to the frame size and interrupting capacity of the breaker

·         30:  800A frame size, 30,000 Amp interrupt capacity at 480VAC

·         50:  1600A frame size, 50,000 Amp interrupt capacity at 480VAC

·         75:  3200A frame size, 65,000 Amp interrupt capacity at 480VAC

·         100:  4200A frame size, 85,000 Amp interrupt capacity at 480VAC

·         125:  5000A frame size, 100,000 Amp interrupt capacity at 480VAC

<5>  Refers to special features of breaker

• H:  Indicates High Interrupt Breaker
• AKR-30H:  42,000 amp interrupt at 480VAC
• AKR-50H:  65,000 amp interrupt at 480VAC
• AKR-75H;  85,000 amp interrupt at 480VAC
• L:  Indicates extra high interrupt AKR-30,  AKR-30L is 65,000 amp interrupt at 480VAC
• E:  Indicates high interrupt 4000A frame, AKR-7D-100E is 200,000 amp interrupt at 480VAC

Note:  This article is intended to assist in identifying AKR circuit breakers.  It should not be used as an absolute guide as it is possible to have any number of modifications that could result in misleading nameplate information.  Please call 1-800-909-3660, email sales@naswgr.com or visit www.naswgr.com for more information about General Electric AKR circuit breakers.