This is typically somewhere between 240vac 600vac, 3 phase power. Determine the sccr of all individual power components by one of the following methods. This method is based upon the weakest link approach. This guide is not intended to be used in lieu of ul 508a or other regulatory standards.
Sccr rating marked on the component use assumed sccrs in table sb 4. Shortcircuit current rating markings are not required for industrial control panels containing only control circuit components. While that seems a reasonable request, and is certainly in the best interest of safety, in practice it can be difficult to comply with. Purcell systems manufactures ul 508a certified enclosures and cabinets to the ul 508a safety standard this manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent damage to property. Because electrical design stands ul and iec differ, it can be challenging to meet all market requirements in a single design. Underwriters laboratory implemented ul508a supplement sb to. Ul standard for safety for industrial control panels.
Underwriters laboratory implemented ul 508a supplement sb to require compliance by ul authorized panel builders. The power circuit supplies electricity to the workers that do the heavy lifting, powering large motors, for example. Ul 508a standard pdf download a1d9fc608e share on facebook in industrial control panels according to ul508a. All components in power circuit must have ratings ratings of starters are typically based on hp rating supplement sb, table sb4. Join us for a 3hour training session on equipment shortcircuit current ratings sccrs and national electrical code nec requirements, understanding industrial control panels devices, and ul 508a supplement sb. Determine the sccr of all individual power components and ul approved series ratings. Formerly supplement sa of ul 508a 1 listed components 1. Test each panel construction and record the construction in a followup procedure. The second day instructs industrial control panel customers on how to establish shortcircuit ratings for individual industrial control panels in accordance with the requirements outlined in the new standard for industrial control panels, ul 508a, 3rd edition, supplement sb. This white paper explains how ul 508a supplement sb is used to determine panel sccr and how. The table below is extracted from the ul 508a supplement sb, table sb4. The process for ul 508a, supplement sb analyzes the sccr for power circuit components, determines if these ratings can be raised by currentlimiting devices in the feeder circuit, and compares the lowest component rating with the lowest interrupting rating of overcurrent devices to determine the assembly sccr.
Global control panel design industrial control panel. Ul 508a supplement sb ul 508a supplement sb describes three steps to determine the sccr of industrial control panels. The ul 508a listing mark on an industrial control panel provides evidence of third party certification to the municipal inspection authority and to the purchaser of the panel. Prior to the release of the latest edition of ul 508a, supplement sb dated december 20, 20, sccr applied only to the power circuit of a control panel. Shortcircuit current rating application and codes training. How to determine shortcircuit current ratings iaei magazine. Ul now offers the ability to purchase a premium hard copy of any ul standard. Shortcircuit calculation control panel tips siemens global. Our icp shop program allows manufacturers who custom build or massproduce icps in the u. Nec article 409 and ul 508a shortcircuit current rating sccr of industrial control panels.
This white paper explains how ul 508a supplement sb is used to determine panel sccr and how the use of typetested components and current. Ul 508a supplement sb sccr method ul 508a supplement sb describes three steps to determine the sccr of industrial control panels. This supplement is the only method specifically noted as being. Always consult all pertinent actual regulatory standards and local standard representatives to ensure full compliance. Basic steps for calculating the sccr of a control panel. Ul 508a covers industrial control panels and industrial panel enclosures operating at 600. Harmonization of iec and north american safety standards. Underwriters laboratory 508a overview of ul508a supplement sb ul 508a is a safety standard for industrial control panels adopted by underwriters laboratory, which is an approved method in determining sccr referenced by nec article 409. Please allow ample time for delivery through the us postal service.
Underwriters laboratory implemented ul508a supplement sb. Purchase ul standards online official ul standards sales. Ul 508a industrial control panels power distribution and control. How to ensure troublefree approval of your ulcompliant. Ul 508a online certifications directory outline of ul 508a slide 3 industrial control procedure ul508a descriptive procedure part 1 general use supplement sa specific component requirements part 2 specific use information you provide specific components not. Ul 508a supplement sb provides a method of assigning the sccr to an icp based on the types of overcurrent protective devices and the ratings of components used within the panel. Design of a motor circuit as per standard ul 508 part iv and ul 508a chap. Equipment sccr, industrial control panel devices and ul 508a supplement sb. Do you design and build industrial control panels or machinery that is used across the world. Ul508a supplement sb4 is the approved method for determining short circuit. Apr 06, 2018 equipment sccr, industrial control panel devices and ul 508a supplement sb.
Identify the lowest component sccr andor component combination sccr rating with an overcurrent protective device ocpd. Page ul enclosed sccr 1 air ul 508a ul 508a 1995 376. Studio 5000 faq, goodbye legacy l4x controllers, graceport. Overview of supplement sb from the ul 508a standard.
In the case of a motor feeder, a number of component combinations may be used to ensure the functions, however. A ul 508a certification is an industrial control panel directive, which electrical inspectors look for. Calculating shortcircuit current rating control panel. For each, protection and control functions are stipulated. Ul 508a supplement sa specific component requirements. Industrial control panels and the panel shop program. With standardization, we can help you achieve a global design that is fit for all markets while saving on engineering time and costs. Jul 07, 2015 in 2005 ul 508a was changed to require control panel builders to include a short circuit current rating on the control panel assembly. Shortcircuitbased configuration of the industrial control panel shall be performed by the manufacturer. Each license entitles a user to download the file to their pc and print 1 copy. The ul listing mark on an industrial control panel provides evidence of third party certification to the municipal inspection authority and to the purchaser of the panel. A brief history of ul 508a and tips for how control panel. Control panels containing predominately communication equipment, such as telephone equipment and intended for installation in accordance with chapter 8 of the nec, is evaluated to the standard for information technology equipment safety part 1. Once the file has opened, it will be locked to the users computer.
Requirements for industrial control panel safety, implications of ul. The industrial control panel shall be designed so that it supports the specified sccr. Nec requirements for shortcircuit current ratings iaei. Overview of code changes in nec article 409 overview of ul 508a supplement sb. Supplement sb says that the sccr of an icp is equal to the sccr of the. Determining sccr for industrial control panels and.
Ul508a is the ul standard for the construction of industrial control panels. June 2018 55 may 2018 90 april 2018 36 march 2018 35 february 2018 28 january 2018 24 december 2017 17 november 2017 17. Ul 508a standard for industrial control panels purcell systems. Ul 508a provides analytical method for determining panel. Ul 508a certification is an industrial control panel directive, which is sought by electrical inspectors. In 2005 ul 508a was changed to require control panel builders to include a short circuit current rating on the control panel assembly. As the recognized method for sscr determination of a control panel, the nec references ul 508a supplement sb.
Requirements for industrial control panel safety, implications of ul 508a 2nd edition. Ansiul 508a, standard for industrial control panels, supplement sb, is an example of an approved method. The sccr requirements for ul 508a are effective after april 25, 2006. Ansi ul 508a, standard for industrial control panels, supplement sb, is an example of an approved method. Nec article 409 and ul 508a shortcircuit current ratings sccr. Latest facebook app for nokia s40 latest facebook app for n.
Ul 508a, but is by no means an exhaustive guide, and does not cover all uses and applications associated with ul 508a regulations. With the numerous possibilities for product combinations within a panel, this option will require a tremendous investment in testing and maintenance. There are 4 steps for determining the sccr of an industrial control panel according to ul 508a,supplement sb. Ul 508a supplement sb ul508a is a safety standard for industrial control panels adopted by underwriters laboratory which is an approved method in determining sccr referenced by nec article 409. Equipment intended to be connected to a source of supply greater. Underwriters laboratory implemented ul508a supplement. Ul 508a covers industrial control panels and industrial panel enclosures operating at 600 volts.
Control panels containing predominately communication equipment, such as telephone equipment and intended for installation in accordance with chapter 8 of the nec, is evaluated to the standard for information technology equipment safety. Ul 508a standard pdf download gaaphakerslingbeachs blog. Requirements for industrial control panel safety, conductors. Ul 508a standard pdf download a1d9fc608e share on facebook. Ul 508a industrial control panels power distribution and. Please refer to the ul website to view the most uptodate table sb4. Ul 508a, supplement sb, provides an analytical method to determine the shortcircuit current rating of an industrial control panel. Each copy is watermarked with the purchasers information. Ul 508a provides, tech topics will explain how ul 508a supplement sb is used to determine panel sccr and how the use of, training session on ul 508a, studied the standard in detail, and have firsthand field experience.
Modify the sccr of certain series combinations if currentlimiting devices are used in the feeder circuit. Supplement sb is the ul approved method for determining the sccr for industrial control panels based on the power circuit components within the. Ul 508a standard for industrial control panels standards. Ul 508a, supplement sb is an approved method to determine sccr for industrial control panels and industrial machinery control panels.
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