1. Suggestion on How to Use
Industry Trainers are encouraged to use this material in their sessions
Download the presentation file
Print the Notes pages and read them as you view the presentation in the “Slide Show” view. In this way you see the slides in large format and have animation (when available)
Suggestion on How to Use
Download the presentation file. Print the Notes pages and read them as you view the presentation in the “Slide Show” view. In this way you see the slides in large format and have animation (when available).

2. SCCR for Industrial Control Panels

3. Interrupting Rating (of Overcurrent Devices)
NEC® Article 100 Definition
Highest current an OVERCURRENT DEVICE (fuse or circuit breaker) is rated to safely interrupt.
Self protection rating only
NEC® Interrupting Rating.
Requires the overcurrent device to have an interrupting rating not less than the maximum available short-circuit current.
The maximum short-circuit current must be calculated and varies, based on system size/location.
Similar Requirements in OSHA (b)(4)
One of the basic ratings of overcurrent devices is interrupting rating. Interrupting rating is the highest current at rated voltage that a device is identified to interrupt under standard test conditions.
NEC requires equipment intended to break current at short-circuit levels to have an interrupting rating sufficient for the nominal circuit voltage and the current that is available at the line terminals of the equipment. Therefore if the available short-circuit current (which is determined by calculations) is 50,000A, overcurrent devices applied must have an interrupting rating of 50,000A or greater.

4. Short-Circuit Current Ratings (of Equipment)
NEC® Article 100 Definition
The highest current EQUIPMENT can withstand without extensive damage (fire or shock hazard).
Combination of equipment/component and overcurrent device
May be based on a specific type of overcurrent device
NEC® Circuit Impedance, Short-Circuit Current Ratings, and Other Characteristics.
Requires the equipment to have a short circuit current rating not less than the maximum available short-circuit current.
The maximum short-circuit current must be calculated and varies based on system size/location.
Similar Requirements in OSHA (b)(5)
The next basic overcurrent protection rating deals with component protection and short-circuit current ratings. The short-circuit current rating of a component identifies the maximum short-circuit current to which the component can be applied. In some cases, the short-circuit current is dependent upon a specific type and size of overcurrent protective device.
NEC requires the proper application of component short-circuit current ratings as shown:
NEC Circuit Impedance and Other Characteristics
The overcurrent protective devices, the total impedance, the component short-circuit current ratings, and other characteristics of the circuit to be protected shall be selected and coordinated to permit the circuit-protective devices used to clear a short-circuit to do so without extensive damage to the electrical equipment of the circuit.
The last part of NEC states: This fault shall be assumed to be either between two or more of the circuit conductors or between any circuit conductor and the equipment grounding conductor(s) permitted in Listed equipment applied in accordance with their listing shall be considered to meet the requirements of this section.
The last part of NEC stresses the importance of properly applying components in accordance with their listing. For instance, if a product has a short-circuit current rating of 100kA with a 100A Class J fuse, it would not be proper to apply the component with protection from a 100A circuit breaker, even if the circuit breaker had an interrupting rating of 100kA. Protection at short-circuit currents of 100kA can only be assured by a 100A Class J fuse according to the component listing.
CEC Appendix B (14-012) has wording similar to NEC

5. SCCR Marking Requirements
430.8 – Marked on motor controllers
440.4(B) – Marked on HVAC equipment
(4) – Marked on industrial control panels
– Short-circuit current cannot exceed marked SCCR
670.3(A)(4) – Marked on industrial machinery control panel
670.5 – Short-circuit current cannot exceed marked SCCR
Typically HVAC, ICPs and IM is rated only 5kA!
Several sections of the NEC require components or equipment electrical panels to be marked with their short-circuit current rating (SCCR).
430.8 – Requires motor controllers to be marked. There are three exceptions:
For fractional horsepower motor controllers
Two horsepower or less general-purpose motor controllers, and
Where the short-circuit current rating is marked on the assembly
440.4(B) – Requires HVAC equipment to be marked. There are three exceptions:
One and two family dwellings
Cord and attachment-plug connected equipment, or
Equipment on a 60A or less branch circuit (This exception is expected to disappear in the 2017 NEC)
(4) – Requires industrial control panels to be marked with their short-circuit current rating.
SCCR marking is not required for panels that contain only control circuit components.
requires that industrial control panels be installed so that their SCCR is not exceeded.
670.3(A)(4) – Requires industrial machinery control panels to be marked with their SCCR.
requires that industrial control panels be installed so that their SCCR is not exceeded.

6. Short-circuit Current Marking Requirement
Available Fault Current.
(A) Service equipment in other than dwelling units must be marked with the maximum available fault current and date of calculation
(B) If short-circuit current increases due to system modification, the marking must be updated.
requires that service equipment, for other than dwelling units, must be marked with the maximum available short-circuit current. This value is meant to be used for determination of interrupting ratings and short-circuit current ratings. If the available short-circuit current changes significantly, the label must be updated, and the equipment upgraded if interrupting ratings or short-circuit current ratings are no longer adequate.

7. How to Comply?
All equipment must comply with: NEC (IR) & (SCCR)
Engineer – Calculate
Contractor – Label
Isc = 60,142 A
Service Equipment
Max Avail. Fault Current = 58,524 A
Date Determined/Calculated: 9/2010
Required per NEC
Isc = 42,153 A
Isc = 18,752 A
This is a one-line diagram showing the available short-circuit current at the secondary of the transformer, at the line side of the service disconnect, and at the line side of various types of equipment. The SCCR of each piece of equipment exceeds the available short-circuit current at that piece of equipment, meeting
Isc = 27,532 A
Isc = 38,525 A
HVAC
SCCR = 40kA
Motor Controller
SCCR = 25kA
Industrial Machinery Panel
SCCR = 65kA
Industrial Control Panel
SCCR = 30kA

8. What is Typical for Industrials?
These charts show the typical distribution of available short-circuit currents at food and beverage facilities and at manufacturing plants in general. 10% of the food and beverage facilities had less than 35kA available, while 28% of all manufacturing facilities had more than 65kA available.

9. How to Determine SCCR? Short-Circuit Current Rating (SCCR)
Can be established by testing during the listing and labeling process OR
Can be determined using an approved (calculation) method
UL 508A Supplement SB is an approved method (industrial control panels and industrial machinery control panel)
AHJ Approved Method
NRTL field evaluation can also be used.
Short-circuit current rating can be established by testing during the Listing and Labeling process or the SCCR can be determined using an approved (calculation) method. Articles 409 and 670 of the NEC indicate that UL 508A Supplement SB is an approved method.
Testing may achieve a higher industrial control panel SCCR because components can be damaged as long as there is no fire or shock hazard. However, the use of UL 508A Supplement SB is often preferred in lieu of testing due to cost considerations. Therefore, most industrial control panels use UL 508A Supplement SB to determine the SCCR.
Where industrial control panels are installed without an SCCR label, a Field Evaluation, such as that available from UL, can be used to determine the SCCR.

10. Industrial Control Panel SCCR
An industrial control panel is an assembly that consists of at least two components. They may be “power” components such as motor controllers, overload relays, fused disconnect switches, and circuit breakers, or they may be “control circuit” components such as push buttons, pilot lights, selector switches, timers, switches, and control relays, or they may be a combination of “power” and “control circuit” components. The controlled equipment is not considered to be a part of the industrial control panel.
Industrial Control Panel.
An assembly of two or more components consisting of one of the following:
power circuit components only, such as motor controllers, overload relays, fused disconnect switches, and circuit breakers;
control circuit components only, such as push buttons, pilot lights, selector switches, timers, switches, and control relays;
a combination of power and control circuit components. These components, with associated wiring and terminals, are mounted on, or contained within, an enclosure or mounted on a subpanel.
The industrial control panel does not include the controlled equipment

11. UL 508A Supplement SB
What Needs to be Analyzed per UL 508A, Supplement SB?
All power circuit components
Feeder and branch circuit components that supply power to loads (motors, lighting, heating and appliances)
Includes disconnect switches, fuses, circuit breakers, load controllers, overload relays, power distribution/terminal blocks, bus bars, etc.
The Exception for HVAC equipment rated 60A or less deleted in 2017 NEC.
Control circuit components are NOT required to be analyzed
Pushbuttons, pilot lights, selector switches, timers, control relays, etc.
What needs to be analyzed? It is important to note that not all components need to be analyzed, only power circuit components. If the control panel contains only control circuits, an SCCR is not required per the exception in NEC (4) and UL 508A. The Exception for HVAC equipment rated 60A or less deleted in 2017 NEC.
UL 508A SB 4.1 identifies how to determine the overall SCCR of an industrial control panel. The first step is to establish the SCCR of individual power circuit components as specified in SB Power circuit components (refer to definition of power circuit, feeder circuit and branch circuit in UL 508A) include all feeder and branch circuit components that supply power to loads. Power circuit components include disconnect switches, fuses, circuit breakers, load controllers, overload relays, power distribution/terminal blocks and bus bars.
Control circuit components are not required to be analyzed. Per UL 508A, these include pushbuttons, pilot lights, selector switches, timers and control relays.

12. “2 Sweep” Method (Based on UL 508A)
Sweep 1 – Component Rating
Determine lowest power circuit component SCCR
Use current-limiting overcurrent protective devices or transformers in feeder circuit to increase low SCCRs downstream
Sweep 2 – Overcurrent Protective Device Rating
Determine lowest overcurrent device IR or combination motor controller SCCR
Lowest value of Sweep 1 and 2 = Assembly SCCR
Called the 2-Sweep method, the first sweep looks for the lowest SCCR of all the power components. In some cases the SCCR of those components can be increased by utilizing an upstream transformer or by utilizing an upstream current limiting fuse or current limiting circuit breaker. The second sweep looks for the lowest interrupting rating of all overcurrent protective devices or the lowest SCCR of combination motor controllers. The SCCR for the assembly is the lowest of the results from Sweep 1 or Sweep 2. It’s looking for the weakest link in a chain.

13. What are the Rules (Sweep 1)?
UL 508A Supplement SB
What are the Rules (Sweep 1)?
Lowest component SCCR limits assembly SCCR unless:
Combination ratings can be used to increase branch circuit component ratings – check with component manufacturer
After identifying the SCCR of components, it is important to understand the UL 508A Supplement SB rules for determining the assembly SCCR.
The first rule to be analyzed is how components, those marked with a short-circuit current rating, affect the assembly SCCR. We will address overcurrent devices, those marked with an interrupting rating or sometimes a short-circuit current rating (such as Type E starters which provide branch circuit ovecurrent protection) later.
In general, the lowest component SCCR limits the assembly SCCR unless:
Combination ratings can be used to increase branch circuit component ratings
This could include a component with marked/specified OCPD. For instance it could be the use of UL Listed Combination motor controllers (UL posts spreadsheets of these ratings on their website) or the markings on power distribution blocks.
To verify combination ratings, it is often necessary to check with the component manufacturer.
Feeder components are used that limit the short-circuit current, reducing the need for higher branch circuit component SCCR
Current-limiting fuses or marked “current-limiting” circuit breakers can be used.
For fuses, Table SB4.2 (not manufacturer specific data) is used to determine the let-through of the fuse (for any manufacturer). These are the Ip and I2t let-through limits for each class of fuse from UL 248. Fuse manufacturers verify compliance with these le-through limits during follow-up testing.
For circuit breakers, published let-through curves are used (published by the circuit breaker manufacturer). The values used are verified by UL in testing performed by the manufacturer to assure compliance.
Transformers rated 10 KVA or less (see SB 4.3.1)
Transformers limit the short-circuit current based upon KVA size and impedance. UL 508A has determined let-through currents for transformers 10kVA or less (for any primary short-circuit current or impedance).

14. Combination Ratings - Feeder
Component SCCR
OCPD I.R.
Nameplate
480
SCCR:
Voltage:
100kA
200kA
100 kA
100 kA
Use combination ratings with specified/marked OCPD to fix low rated feeder components
Note: PDB must have feeder circuit spacings (Listed vs. Recognized)
200 kA
200 kA
200 kA
The fix for low SCCR branch circuit components is to find components with high SCCR combination ratings. These are ratings for a specific overcurrent device and component. For the combination rating to apply, the specified (from instructions) or marked overcurrent device must be provided.
Note:
Some enclosed combination motor controller short-circuit current ratings may use overcurrent devices with interrupting ratings lower than the combination SCCR as permitted per UL 508 – Standard for Industrial Control Equipment. For instance a 14kA interrupting rating circuit breaker may have a combination rating with a motor starter for 25kA. The motor starter can be considered to be 25kA but SB or would suggest that the SCCR for the circuit breaker should be considered 14kA.
Instantaneous trip circuit breakers (MCP) are unmarked overcurrent devices and must be used only in conjunction with a listed, tested Type D combination motor controller. Because of this, a Square D MCP can not be used with an Eaton motor controller as it will not be a tested, listed combination. Where MCPs are used as part of a listed, tested, Type D combination motor controller, the short-circuit current rating of the MCP is considered equal to the combination motor controller rating.
100 kA
100 kA
100 kA
Combination ratings of overcurrent protective devices and components can be used

15. Combination Ratings - PDBs
PDB w/14 AWG Load Side Conductors SCCR=100kA w/175A Class J fuse or smaller
PDB w/12 AWG Load Side Conductors SCCR=200kA w/200A Class J fuse or smaller
This is a partial data sheet for a finger-safe power distribution block. It shows that the SCCR is 100kA when 14 AWG conductors are used while upstream protection is a Class J fuse, no larger than 175 amperes. When using 12 AWG with that same PDB, the SCCR is 200kA, as long as the upstream Class J fuse is not larger than 200 amperes.

16. Combination Ratings - Branch
Component SCCR
OCPD I.R.
Nameplate
480
SCCR:
Voltage:
100kA
200kA
100 kA
100 kA
Use combination ratings with specified/marked OCPD to fix low rated branch components
200 kA
200 kA
200 kA
The fix to low SCCR branch circuit components is to find components with high SCCR combination ratings. These are ratings for a specific overcurrent device and component. For the combination rating to apply, the specified (from instructions) or marked overcurrent device must be provided.
Note:
Some enclosed combination motor controller short-circuit current ratings may use overcurrent devices with interrupting ratings lower than the combination SCCR as permitted per UL 508 – Standard for Industrial Control Equipment. For instance a 14kA interrupting rating circuit breaker may have a combination rating with a motor starter for 25kA. The motor starter can be considered to be 25kA but SB or would suggest that the SCCR for the circuit breaker should be considered 14kA.
Instantaneous trip circuit breakers (MCP) are unmarked overcurrent devices and must be used only in conjunction with a listed, tested Type D combination motor controller. Because of this, a Square D MCP can not be used with an Eaton motor controller as it will not be a tested, listed combination. Where MCPs are used as part of a listed, tested, Type D combination motor controller, the short-circuit current rating of the MCP is considered equal to the combination motor controller rating.
100 kA
100 kA
100 kA
Combination ratings of overcurrent protective devices and components can be used

17. Combination Ratings – Motor Starter & Contactor
The fix to low SCCR branch circuit components is to find components with high SCCR combination ratings. These are ratings for a specific overcurrent device and component. For the combination rating to apply, the specified (from instructions) or marked overcurrent device must be provided.
Note:
Some enclosed combination motor controller short-circuit current ratings may use overcurrent devices with interrupting ratings lower than the combination SCCR as permitted per UL 508 – Standard for Industrial Control Equipment. For instance a 14kA interrupting rating circuit breaker may have a combination rating with a motor starter for 25kA. The motor starter can be considered to be 25kA but SB or would suggest that the SCCR for the circuit breaker should be considered 14kA.
Instantaneous trip circuit breakers (MCP) are unmarked overcurrent devices and must be used only in conjunction with a listed, tested Type D combination motor controller. Because of this, a Square D MCP can not be used with an Eaton motor controller as it will not be a tested, listed combination. Where MCPs are used as part of a listed, tested, Type D combination motor controller, the short-circuit current rating of the MCP is considered equal to the combination motor controller rating.

18. High Fault Current Substitution with Current-Limiting Overcurrent Device
SB4.2.3 A high fault short circuit current rating for a motor controller, an overload relay, or a combination motor controller, as specified in SB4.2.2 (a) or (c), shall only be used as the short circuit current rating of the component when the specified branch circuit protective device is provided.
Exceptions:
CL Fuse with more CL Fuse
Provided in the field if marked
CL CB with more CL CB
NEW Exception No. 4: When the specified branch circuit protection related to the high fault short- circuit current rating is a non-current limiting overcurrent device, a current-limiting overcurrent device is able to be used at the same high fault rating where the interrupting rating of the current- limiting overcurrent device is equal to or greater than the specified overcurrent device.
In some cases, manufacturers may have tested and listed combination ratings with non-current-limiting overcurrent protective devices, but not with current-limiting overcurrent protective devices. New Exception No. 4 allows current-limiting overcurrent protective devices to be substituted for non-current-limiting overcurrent protective devices without reducing the short-circuit current rating.
Current limiting overcurrent devices can be used in lieu of a non-current limiting overcurrent device for protection of motor controllers and still maintain a high fault short circuit current rating.

19. Use of CL Devices - OCPD CL Device must be in the feeder circuit
For CL Fuses or Circuit Breakers
Use PEAK Let-through, Not RMS Let-Through (more conservative). Compare peak let-through with component SCCR
Fuses - cannot use manufacturer specific fuse data – only tables (or formulas) based on performance requirements from UL 248 (conservative - applies to all manufacturers)
Circuit Breakers - must be Listed and marked “current- limiting” and use published peak let-thru curves
Can only raise downstream branch circuit component SCCR (not fuse IR, not CB IR, not fuse/CB series rating, not CB/CB series rating, not combination motor controller SCCR)
New - can be provided in the field (outside of panel) if properly marked on industrial control panel.
Current limiting fuses or current limiting circuit breakers can be used in the feeder (or main) to protect downstream components. This does not include raising the interrupting rating of downstream fuses or circuit breakers. It does not include raising a series rating. It does not include raising the SCCR for a combination motor controller. The upstream current limiting fuse or current limiting circuit breaker can be outside the panel if it is properly marked on the panel.

20. Feeder vs. Branch Circuits
Feeder Circuit
Branch Circuit
On this wiring diagram, the part in purple is considered the feeder circuit. The parts in light blue are considered branch circuits.
Branch Circuit

21. Use of CL OCPD can only fix components
Use of CL Devices - OCPD
Component SCCR
OCPD I.R.
Nameplate
480
SCCR:
Voltage:
15kA
FC LT
50kA kA
100kA 14kA
200kA 20kA
200kA
18kA F B
Current limiting feeder OCPD can be used to increase branch component SCCR.
If Component SCCR is less than let-through current at a given short-circuit current, raise component SCCR to that short- circuit current value.
200 kA
18 kA
18 kA
Another way to fix to low rated branch circuit components is to use current-limiting overcurrent devices in the feeder circuit.
In this case, the current-limiting overcurrent device in the feeder had a peak let-through current (click) of 14kA or less at a short-circuit current of 100kA. Thus, if a 100kA short-circuit were to occur, only 14kA or less would be let-through to downstream components. Because of this, the downstream component short-circuit current ratings are raised from 15kA (click) to 100 kA, but the assembly SCCR is still limited to 18kA because of the 18kA interrupting rating of the two overcurrent protective devices. If those two overcurrent protective devices were replaced by overcurrent protective devices with a 100kA or 200kA interrupting rating, the assembly SCCR would be 100kA.
To the determine the let-through, see Table SB4.2 for current-limiting fuses or manufacturer published let-through curves for circuit breakers marked “current-limiting”.
Note: the let-through current can NOT be used to raise overcurrent protective device device interrupting ratings. This is clearly indicated in UL 508A SB and SB Because of this, the use of series combination ratings or series ratings (manufacturer tested ratings between overcurrent devices and a lower interrupting rated circuit breaker) are not allowed for use in industrial control panels. This rule also applies for devices with short-circuit current ratings that are used for branch circuit overcurrent protection – such as Type E starters or MCPs.
15 kA
100 kA
100 kA
15 kA
100 kA
15 kA
Use of CL OCPD can only fix components

22. Current-Limiting Feeder Protective Devices Installed in the Field
NEW:
SB4.3.4 The specified circuit breaker marked "current limiting" or current-limiting Class of fuse supplied in the feeder circuit that limits the peak let-through current available in accordance with SB and SB4.3.3 is able to be provided in the field when the panel is marked in accordance with SB5.1.3.
SB5.1.3 An industrial control panel marked with a high fault short circuit current rating and is not provided with the required feeder circuit protective device as specified in the SB4.3.4 shall be marked with the type and size of feeder circuit protection required to be installed in the field. This marking shall be included as part of the marking in SB5.1.1.
Allows the use of the let-through to increase branch component SCCR even if the current-limiting overcurrent device is supplied in the field, provided the associated required marking is provided including the SCCR marking.
Remote current-limiting fuses or remote current-limiting circuit breakers are allowed to provide the necessary protection for downstream components if the equipment is so marked.

23. Use of CL Devices - Transformers
CL Transformer must be in feeder
Previously only 5 or 10KVA Transformers
Now Use Equations or Tables
This shows two tables that provide the maximum available short-circuit current for single phase and three phase transformers. For example, the maximum short-circuit current that can be delivered by a single phase, 10 kVA transformer, with a 240 volt secondary, is amperes. These tables are based upon transformers with a 2.1% impedance. If the actual impedance is less than 2.1%, the short-circuit current should be calculated. It is the transformer FLA times 100 and divided by the impedance.

24. Use of CL Devices - Transformers
Component SCCR
OCPD I.R.
Nameplate
480
SCCR:
Voltage:
200kA
5kA
10 kA
200kA
200 kA
10 kVA
V, single phase, 2.1 impedance or more
Max short-circuit from table 3970A
If OCPD IR/Components SCCR is higher, then assign entire circuit I.R. of primary overcurrent device
UL has determined, based on calculations, with transformer size (kVA) the maximum let-through short-circuit current for transformers. This assumes infinite primary current and typical values for transformer impedance.
For transformers of 10kVA or less, the maximum let-through current is typically 5kA or less. Thus if the secondary component SCCRs are equal to or greater than 5kA, the SCCR can be considered equal to the interrupting rating of the primary overcurrent device. In the example shown, since this condition is met, the entire circuit can be considered to be 200kA. This shows the benefit of using overcurrent devices with high interrupting ratings, such as current-limiting fuses ahead of small transformers.
For transformers of 5kVA or less, with a 120V secondary, the maximum let-through current is typically 2kA or less. Thus if the secondary components have an SCCR equal to or greater than 2kA, the SCCR can be considered equal to the interrupting rating of the primary overcurrent device.
Use of transformers can increase secondary component/OCPD ratings

25. UL 508A Supplement SB Reviewing the Rules for Sweep 2
Lowest overcurrent protective device interrupting rating (or SCCR for some devices) always limits assembly SCCR
All Feeder and branch circuit overcurrent devices
Tested series combination ratings or series ratings (fuse-circuit breaker or circuit breaker-circuit breaker) are NOT allowed.
Branch circuit overcurrent devices, connected to the feeder circuit, supplying a control circuit.
Supplemental protective devices, protecting the control circuit transformer, in a motor branch circuit.
The devices that must be considered are the overcurrent protective devices with interrupting ratings (or short-circuit current ratings for some devices such as Type E starters and MCPs when used in conjunction with a motor controller and listed as a Type D combination motor controller). The ratings of these devices ALWAYS limit the assembly SCCR. This is clearly stated in SB and SB The only time an overcurrent device interrupting (or SCCR for some devices) can be raised is by the transformer let-through rules per SB
Note tested series combination ratings or series ratings (current-limiting fuse and low interrupting rating circuit breaker or circuit breaker and low interrupting rating circuit breaker) are also NOT allowed. The use of tested series ratings of overcurrent devices are only permitted in panelboards or switchboards. The reason is that industrial control panels do not have set construction requirements like panelboards and switchboards.

26. Why High SCCR? NEC & Equipment standards require the SCCR to be marked
NEC requires the marked value to be adequate for the maximum available short-circuit current
High SCCR is often preferred
Flexibility of application
Multiple installations
Short-circuit current unknown
Insufficient SCCR can delay installation
Design considerations involve the actual installation of equipment.
For instance, one needs to consider what is the SCCR required by the customer based on the short-circuit current where the equipment is going to be installed. Understand that different customers have different short-circuit current levels and associated SCCR requirements.
Second, consider flexibility of application. This is important if equipment is going to a variety of installations. It is much better to have a high assembly SCCR that covers all installations where the equipment could be applied. Likewise a high assembly SCCR reduces the possibility of a problem where the short-circuit current is unknown.
Finally, understand that if equipment does not have a sufficient SCCR for the short-circuit current available where installed, the inspector could red-tag the equipment. In this case, design changes need to be made to the equipment which may require shipping the equipment back to the panel builder for modification, resulting in project delays.

27. Fix It - Solutions High I.R. Protective Devices Class R Class J
Class J Drive Fuse
Class T
Class CC
CubeFuse
High Speed
High IR/CL CBs
The Eaton Bussmann Series “Fix-It” Solutions include high interrupting rated current-limiting fuses.
The Low-Peak Yellow Fuses are a perfect solution where high assembly SCCR is needed. Use of LP-CC, LPJ, LPN-RK/LPS-RK or the CUBEFuse is an economical way to help achieve high assembly SCCR.

28. Fix It - Solutions High SCCR Components
The Eaton Bussmann Series “Fix-It” Solutions also include high SCCR components.
These components include:
Finger-safe power distribution blocks (PDBFS) with high SCCR
Finger-safe modular fuse holders (CH_CC, CH_J and OPM-NG-SC3) with high SCCR
Non-fused switches (CDNF).
The CDNF16 to CDNF32 (UL 508) is rated for use in a motor branch circuit as a motor controller and suitable as motor disconnect when on the load side of the final branch circuit overcurrent protective device.
The CDNF30, 60, etc. (UL 98) is rated for use as a feeder or branch disconnect for any circuit. The CDNF30, 60, etc has an SCCR with upstream fuses of 50kA or higher.
The New Compact Circuit Protector (CCP) – Class CC or CUBEFuse Version is a UL 98 rated disconnect with a 200kA SCCR.
Fusible Disconnects - UL 98 rated disconnect with Class CC or J fuses.