Background Statement for SEMI Draft Document #4575

Background Statement for SEMI Draft Document #4575 Line Item Revisions to SEMI S2, Environmental, Health, and Safety Guideline for Semiconductor Manufacturing Equipment (In Delayed Effective Date Format), SEMI S22, Safety Guideline for the Electrical Design of Semiconductor Manufacturing Equipment (In Delayed Effective Date Format), and SEMI S26, Environmental, Health, and Safety Guideline for FPD Manufacturing Equipment (In Delayed Effective Date Format) Note: This background statement is not part of the balloted item. It is provided solely to assist the recipient in reaching an informed decision based on the rationale of the activity that preceded the creation of this document.

Note: Recipients of this document are invited to submit, with their comments, notification of any relevant patented technology or copyrighted items of which they are aware and to provide supporting documentation. In this context, “patented technology” is defined as technology for which a patent has issued or has been applied for. In the latter case, only publicly available information on the contents of the patent application is to be provided.

Note: The Safety Checklist for this document will be reviewed and voted on at the committee meeting where the document is adjudicated.

Note: Additions are indicated by underline and deletions are indicated by strikethrough.

Dear Colleagues,

Several standards (e.g., UL 508A, NFPA 79, SEMI S2, EN 60204-1, SEMI S22, NFPA 70) specify that industrial control panel or the equipment shall be provided with “short-circuit (current) rating”. For example:  NFPA 70-2005, Article 670.3 (A) - Permanent Nameplate. The nameplate shall include the following information: (4) Short circuit current rating of the machine industrial control panel based on one of the following: a. Short circuit current rating of a listed and labeled machine control enclosure or assembly b. Short circuit current rating established utilizing an approved method.  NFPA 70-2005, Article 409.110 - Marking. An industrial control panel shall be marked with the following information that is plainly visible after installation: (3) Short-circuit current rating of the industrial control panel based on one of the following: Short-circuit current rating of a listed or labeled assembly Short-circuit current rating established utilizing an approved method (FPN: UL 508A-2001, Supplement SB, is an example of an approved method).  NFPA 79-2007, Section 16.4.1 - Machine Nameplate Data. A nameplate giving the following information shall be attached to the enclosure: (6) Short-circuit current rating of the control panel.  UL 508A, Industrial Control Panel, First Edition, April 25, 2001 (revised through May 1, 2003) 52.1 An industrial control panel shall be provided with a nameplate that includes the following: b) Complete electrical rating of each source of supply as specified in 49.1 49.5 The input terminals in 49.1 shall have a short circuit current rating. The short circuit rating shall be based on the requirements in Supplement SB. (Effective April 25, 2006).  SEMI S2-0706, Section 13.4.12 – A permanent nameplate listing the manufacturer’s name, machine serial number, supply voltage, phase frequency, short circuit current rating of the equipment or its industrial control panel and…

1  SEMI S22-0706, Section 20.4 i) – Equipment Nameplate – A permanent nameplate should be attached to the main electrical enclosure or equipment where it is plainly visible after installation. This nameplate should include the following information: i) short-circuit current rating of the equipment or its industrial control panel…  IEC 60204-1 (2005), Clause 16.4 - Marking of equipment. Equipment (for example controlgear assemblies) shall be legibly and durably marked in a way that is plainly visible after the equipment is installed. A nameplate giving the following information shall be attached to the enclosure adjacent to each incoming supply: … short-circuit rating of the equipment; … These standards, however, either do not provide any guidance in terms of acceptable methodologies for determining “short- circuit (current) rating”, or simply reference UL 508A (Supplement SB). Manufacturers who attempt to use UL 508A, Supplement SB, as a means for determining short circuit current rating for their control panel or their equipment quickly discover that the method outlined in UL 508A, Supplement SB is unrealistically conservative. Specifically, utilizing UL 508A, Supplement SB, as a method for determining short circuit current rating would generally yield a short circuit current rating which would prevent the industrial control panel or the equipment to be connected to its end use environment, because most facilities (at least in the United States) would have available facilities short circuit current which far exceeds the short circuit current rating for the industrial control panel or equipment, as determined through UL 508A, Supplement SB.

UL 508A, Supplement SB is also not the ideal method for determining short circuit current rating because it requires users to consider short circuit current of all branch circuit components, many of which may not have any short circuit current rating. Supplement SB also does not specifically consider the reduction of short circuit current as a result of conductors which, in the case of an interconnecting cable between different parts of equipment, could be significant, particularly when modules of the equipment are located in separate rooms or separate floors from the equipment’s main control panel.

Another method is to conduct testing which is often destructive for the equipment and very impractical (and questionably within the scope of the standards) when determining the SCCR for the entire piece of equipment and not just a control panel.

In an effort to provide a reasonable solution to the semiconductor industry, a method for determining short circuit current rating is being presented as a Related Information to SEMI S22.

The alternate method outlined in this ballot is based, in part, on the definition of short circuit current rating in the CDV draft version of IEC 60204-33, “short-circuit rating (of the electrical equipment) - maximum input current at which the short- circuit ratings of all the overcurrent protective devices in the equipment are at least equal to the prospective fault current at their point of connection.”

This ballot consists of two line items for delayed implementation to the referenced SEMI documents. The first line item, LI1, is intended to include a means of determining short circuit current rating as part of an additional Related Information in SEMI S22. The second line item, LI2, is intended to revise the definition of short circuit current rating to better align with the definition as proposed in the draft IEC 60204-33.

LI1 – Introduce a means for determining short circuit current rating in SEMI S2, SEMI S22, and SEMI S26.

LI1, Part 1: Revise Note in Section 5.2.72 of SEMI S2 to include reference to Related Information of SEMI S22 as an alternate means for determining short circuit current rating.

LI1, Part 2: Revise Note in Section 5.1.66 of SEMI S22 to include reference to Related Information as an alternate means of determining short circuit current rating.

LI1, Part 3: Revise Note in Section 5.2.83 of SEMI S26 to include reference to Related Information of SEMI S22 as an alternate means of determining short circuit current rating.

LI1, Part 4: Add Related Information to SEMI S22 to include a method for determining short circuit current rating.

Revision 004, April 15th, 2008 2 LI2 – Replace the definition of short circuit current rating in both SEMI S2, SEMI S22 and SEMI S26 to align with the definition of short circuit rating in the draft IEC 60204-33.

LI2, Part 1: Revise definition of short circuit current in ¶5.2.72 of SEMI S2 to align with the definition of short circuit rating in draft IEC 60204-33.

If you have any questions regarding any of the line items in this ballot, please feel free to contact Edward Karl, Applied Materials, [email protected].

3 Safety Checklist for SEMI Draft Document #4575 Line Item Revisions to SEMI S2, Environmental, Health, and Safety Guideline for Semiconductor Manufacturing Equipment, SEMI S22, Safety Guideline for the Electrical Design of Semiconductor Manufacturing Equipment, and

SEMI S26, Environmental, Health, and Safety Guideline for FPD Manufacturing Equipment

Developing/Revising Body Name/Type: SCCR Task Force Technical Committee: EHS, FPD Region: NA

Leadership Position Last First Affiliation Leader Karl Edward Applied Materials Author/Editor* Karl Edward Applied Materials Editor* Larsen Sean AMEC Checklist Karl Edward Applied Materials Author  Only necessary if different from leaders

Revision 004, April 15th, 2008 4 Documents, Conflicts, and Consideration Safety related codes, standards, and practices used in developing the safety guideline, and the manner in which each item was considered by the technical committee # and Title Manner in Which the Standards was Considered in This Safety Guideline UL 508A, Industrial Control Panels Reviewed the procedure for determining Short Circuit Current rating of Industrial Control Panels, as specified in Supplement SB. Cooper Bussmann, Bulletin EPR-1, Reviewed the point-to-point method for determining Short http://www.bussmann.com/library/docs/EPR_ Circuit Current rating from one end of a conductor to Booklet.pdf another, as well as short circuit current rating of transformer output. NFPA 79-2007, Electrical Standard for Reviewed the criteria for short circuit current rating. Industrial Machinery 2007 Edition NFPA 70, National Electrical Code Reviewed the criteria for short circuit current rating in Articles 670.3(A) and Article 409.110. SEMI S2, Environmental, Health, and Safety Reviewed the criteria for short circuit current rating. Guideline For Semiconductor Manufacturing Equipment SEMI S22, Safety Guideline for the Electrical Reviewed the criteria for short circuit current rating. Design of Semiconductor Manufacturing Equipment SEMI S26, Environmental, Health, and Safety Reviewed the criteria for short circuit current rating. Guideline for FPD Manufacturing Equipment IEC 60204-1 Safety of Machinery – Electrical Reviewed the criteria for short-circuit rating. Equipment of Machines, Part 1

Known inconsistencies between the safety guideline and any other safety related codes, standards, and practices cited in the safety guideline # and Title Inconsistency with This Safety Guideline UL 508A, This ballot contains an alternate method of determining short circuit current which is Industrial Control different than that specified in Supplement SB of UL 508A. The Supplement SB Panels approach does not take into consideration the length and size of conductors, whereas this ballot does. This ballot also focuses primarily on the short circuit current rating of the overcurrent protective devices because there are a large number of components in the market where no short circuit current rating is available.

Other conflicts with known codes, standards, and practices or with commonly accepted safety and health principles to the extent practical # and Title Known Conflicts with this Safety Guideline UL 508A, For industrial control panels listed to UL 508A, Supplement SB is specified as the Industrial only accepted method for determining Short Circuit Current Rating for the industrial Control Panels control panel.

5 Participants and Contributors Last First Company Email Karl Edward Applied Materials [email protected] Wong Carl AKT [email protected] Larsen Sean AMEC [email protected] Crane Lauren Applied Materials [email protected] Sigmund Peter Applied Materials [email protected] Hamilton Jeff Applied Materials [email protected] Palmero Edwin Applied Materials [email protected] Mashiro Supika Anelva [email protected] Planting Bert ASML [email protected] DeBoer Dave ASML [email protected] Quince Phil Axcelis [email protected] Brody Steven Brooks [email protected] Yakimow Byron Cymer [email protected] Frankfurth Mark Cymer [email protected] Evanston Chris Earth Tech [email protected] Krauss Mark Environmental, Health and Safety Services, LLC [email protected] Sherman Mike FSI International [email protected] Barcik Steve High Tech Design Safety, LLC [email protected] Guild Ed IBM [email protected] Petry William IBM [email protected] Breder Pavol Intertek [email protected] Johnson Larry Intertek GS3 [email protected] Crockett Alan KLA Tencor [email protected] Oswalt James Mattson [email protected] Greenberg Cliff Nikon [email protected] Cose Allan Novellus [email protected] Kryska Paul Novellus [email protected] Sklar Eric Safety Guru, LLC [email protected] Sawyer (Kennis) Debbie Semitool [email protected] Shigehito Ibuka Tokyo Electron [email protected] Fessler Mark Tokyo Electron America [email protected] Krov Alan Tokyo Electron America [email protected] Hom Jeffrey Underwriters Laboratories [email protected] Rehder Alan Underwriters Laboratories [email protected] McLeod Ian SEMI Standards Staff [email protected]

The content requirements of this checklist are documented in Section 14.2 of the Regulations Governing SEMI Standards Committees.

Revision 004, April 15th, 2008 6 SEMI Draft Document #4575 LINE ITEM BALLOT TO: SEMI S2-0706b, ENVIRONMENTAL, HEALTH, AND SAFETY GUIDELINE FOR SEMICONDUCTOR MANUFACTURING EQUIPMENT (In Delayed Effective Date Format), SEMI S22-0706a, SAFETY GUIDELINE FOR THE ELECTRICAL DESIGN OF SEMICONDUCTOR MANUFACTURING EQUIPMENT (In Delayed Effective Date Format), and SEMI S26-0308, ENVIRONMENTAL, HEALTH, AND SAFETY GUIDELINE FOR FPD MANUFACTURING EQUIPMENT (In Delayed Effective Date Format)

Line Item 1, Part 1a: Revise Note 7 in Section 5.2.72 of SEMI S2 to include reference to Related Information of SEMI S22 as an alternate means for determining short circuit current rating. Text to be removed is shown struck through; text to be added is shown underlined. Only the text that is struck through or underlined is proposed to be changed by this Line Item.

5.2.72 short circuit current rating – the maximum available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected.

NOTE 7: Short circuit current rating for an electrical system is typically based on the analysis of short circuit ratings of the components within the system. See UL 508A and Related Information 2 of SEMI S22 for a methods which may be used to determine short circuit rating.

Line Item 1, Part 1b: Add Notice to Section 5 of SEMI S2 indicating delayed implementation.

NOTICE: Section 5.2.72 will be changed upon 01 July 2009 publication, as shown in Delayed Section X. The EHS Committee has voted that use of the replacement text is optional before the Effective Date.

Line Item 1, Part 2a: Revise Note 12 in Section 5.1.66 of SEMI S22 to include reference to Related Information as an alternate means of determining short circuit current rating. Text to be removed is shown struck through; text to be added is shown underlined. Only the text that is struck through or underlined is proposed to be changed by this Line Item.

5.1.66 short circuit current rating — the maximum prospective available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected.

7 NOTE 12: Short circuit current rating for an electrical system is typically based on the analysis of short circuit current ratings of the components within the system. See UL 508A and Related Information 2 for a methods which may be used to determine short circuit current rating.

Line Item 1, Part 3a: Revise Note 7 in Section 5.2.83 of SEMI S26 to include reference to Related Information of SEMI S22 as an alternate means of determining short circuit current rating. Text to be removed is shown struck through; text to be added is shown underlined. Only the text that is struck through or underlined is proposed to be changed by this Line Item.

5.2.83 short circuit current rating — the maximum available current to which the system supply circuit is intended, by the system manufacturer, to be connected.

NOTE 7: Short circuit current rating for an electrical system is typically based on the analysis of short circuit current ratings of the components within the system. See UL 508A and Related Information 2 of SEMI S22 for a methods which may be used to determine short circuit current rating.

Line Item 1, Part 4: Add Related Information to SEMI S22 to include a method for determining short circuit current rating (in Delayed Effective Date Format).

RELATED INFORMATION 2 METHOD FOR DETERMINING SHORT CIRCUIT CURRENT RATING NOTICE: This related information is not an official part of SEMI S22 and was derived from the work of the global Environmental, Health & Safety Committee. This related information was approved for publication by full letter ballot on ____(date)___.

Revision 004, April 15th, 2008 8 NOTICE: This document contains material that has been balloted and approved by the SEMI Environmental Health and Safety Committee, but is not immediately effective. This material and the date on which it becomes effective are included in the Delayed Revisions Sections X. The provisions of this information are not an authoritative part of the document until their effective dates. The main body of SEMI S22-0706b remains the authoritative version. Some or all of the provisions not yet in effect may be optionally applied prior to the effective date, providing that they do not conflict with provisions of the authoritative version other than those that are to be revised or replaced as part of the deferred change, and are labeled accordingly. Material that is to be replaced by revisions that are not yet in effect is preceded by a NOTICE indicating its status.

R2.1 Introduction

R2.1.1 The method outlined below may be used to determine short circuit current rating of equipment or its industrial control panel. This method primarily involves the review of short circuit current rating or Ampacity Interrupting Current (AIC) rating of overcurrent protective devices within the equipment or its industrial control panel. It also allows for the consideration of current drop across a fixed length of conductor within the equipment or its industrial control panel. Lastly, this method allows the user to calculate a short circuit current available on the secondary side of a transformer.

R2.1.2 To facilitate the determination of the short circuit current rating within the equipment or its industrial control panel, the following information should be gathered:

R2.1.2.1 Whether the short circuit current rating will be applied to the equipment or only its industrial control panel.

R2.1.2.2 The short circuit current rating or AIC rating of all overcurrent protective devices within the equipment or its industrial control panel.

NOTE 1: For the purpose of this method, overcurrent protective device is limited to circuit breakers, branch circuit fuses, and supplementary protective devices (e.g., circuit protectors, supplementary fuses).

R2.1.2.3 The length and size of the conductors for the equipment or its industrial control panel.

R2.1.2.4 Primary and secondary voltage, VA rating, and impedance value of all transformers within the equipment or its industrial control panel.

R2.1.3 Certain assumptions have to be made in order to simplify the short circuit current rating method:

R2.1.3.1 For 3 phase equipment, the method outlined in this Related Information assumes 3 phase fault.

R2.1.3.2 For 3 phase transformers, the method outlined in this Related Information assumes a Y-system with center ground.

R2.1.3.3 For transformers that do not have any Z% impedance rating, the method outlined in this Related Information assumes 3% Z for isolation transformer and 1% Z for autotransformer.

R2.2 Method for Determining Short Circuit Current Rating within the Equipment or its Industrial Control Panel:

R2.2.1 The following steps outline the method for determining short circuit current rating within the equipment or its industrial control panel:

R2.2.1.1 First decide whether the short circuit current rating will be applied to the equipment or only its industrial control panel.

NOTE 2: NFPA 79-2007, UL 508A, National Electrical Code Article 670, SEMI S2 and SEMI S22 require or permit the short circuit current rating to be limited to just the equipment’s industrial control panel. It is, therefore, the equipment supplier’s prerogative to limit the short circuit current rating to the equipment’s industrial control panel.

R2.2.1.2 Identify the short circuit current rating or the AIC rating of the equipment’s main overcurrent protective device and use this value as the initial short circuit current rating for the equipment or its industrial control panel. This short circuit current rating is referred to in this document as “SCCRequipment/panel”.

9 NOTE 3: This “initial” short circuit current rating (“SCCRequipment/panel”) may need to be reduced to ensure that the available short circuit current at each of the downstream overcurrent protective devices within the equipment or its industrial control panel does not exceed the short circuit current rating or AIC rating of each of the overcurrent protective device in question.

R2.2.1.3 With the “SCCRequipment/panel” from the step outline in Section R2-2.1.2 as a starting point, use point-to-point short circuit current calculation method (such as the example in Section R2-3) to determine the available short circuit current (“SCCRavailable”) at the end of the length of conductor(s) terminating at the next downstream overcurrent protective device.

NOTE 4: If the length of conductor between two overcurrent protective devices does not yield a significant reduction in available short circuit current at the point of connection to the downstream overcurrent protective device, it may be simpler to disregard the conductor between overcurrent protective devices and assume that all of the available short circuit current (SCCRavailable) identified for the upstream overcurrent protective device is available at the next downstream overcurrent protective device(s).

R2.2.1.4 Compare the available short circuit current (SCCRavailable) at each of the overcurrent protective device against the short circuit current rating or AIC rating of the overcurrent protective device at that point. If the available short circuit current (SCCRavailable) exceeds the short circuit current rating or AIC rating of the overcurrent protective device at that point, return to the step outlined in Section R2-2.1.2 and reduce the value of the “SCCRequipment/panel” until the SCCRavailable no longer exceeds the short circuit current rating or AIC rating of the overcurrent protective device at that point.

R2.2.1.5 If a transformer is connected between two overcurrent protective devices, the point-to-point short circuit current method (such as the example in Section R2-3) may be used to determine the short circuit current rating at the secondary of the transformer. Once the short circuit current rating for the output of the transformer has been determined, continue downstream to the next overcurrent protective device and identify the short circuit current or AIC rating of that overcurrent protective device.

NOTE 5: For the purpose of this short circuit current method, if impedance (%Z) is not provided on the transformer’s nameplate or specification sheet, assume 3% Z for isolation transformers and 1% Z for autotransformers.

R2.2.1.6 Continue downstream for each overcurrent protective device within the equipment or its industrial control panel, comparing the available short circuit current (SCCRavailable) against the short circuit current rating or AIC rating at each overcurent protective device as outlined in Section R2-2.1.4), until the circuit terminates at a load (e.g., heater, motor, lamps, convenience receptacle).

R2.2.1.7 Repeat steps outlined in Sections R2-2.1.3 through R2-2.1.6 for all circuits within the equipment or its industrial control panel.

R2.2.1.8 The final short circuit current rating for the equipment or its industrial control panel is the lowest SCCRequipment/panel value necessary to ensure that the SCCR available does not exceed any of the overcurrent protective devices within the equipment or industrial control panel.

R2.3 Example of point-to-point short circuit current method:

R2.3.1 The following point-to-point short circuit current method for conductors and transformers is reprinted from http://www.bussmann.com/library/docs/EPR_Booklet.pdf with permission from Cooper Bussmann.

NOTE 6: Point-to-point short circuit current calculators (or software) for conductors and transformers may be commercially available and may be considered suitable for use to minimize manual calculations if the results from the calculator or software yield results similar to those of the approach outlined in § R2-3.

Revision 004, April 15th, 2008 10 11 Revision 004, April 15th, 2008 12 13 Line Item 1, Part 5a: Addition of the Delayed Revision Section to SEMI S2 Related to the definition of Short Circuit Current Rating.

DELAYED REVISIONS SECTION X (EFFECTIVE JULY 1, 2009) CHANGES TO SECTION 5.2.72 INVOLVING DEFINITION OF SHORT CIRCUIT CURRENT RATING

NOTICE: This Delayed Revisions Section contains material that has been balloted and approved by the SEMI Environmental Health and Safety Committee, but is not immediately effective. The provisions of this material are not an authoritative part of the document until their effective date. The main body of SEMI S2-0706 remains the authoritative version. Some or all of the provisions of revisions not yet in effect may be applied prior to the effective date, providing they do not conflict with portions of the authoritative version other than those that are to be revised or replaced as part of the deferred revision, and are labeled accordingly. NOTICE: Unless otherwise noted, all material to be added is underlined, and all material to be deleted is struck through. Note: Section, subsection, paragraph, note, table, and figure numbers that will be determined by their sequence in the document on the effective date are indicated by the character "x".

Dx-1 Revision of Note to the definition of Short Circuit Current Rating to Section 5 (Terminology) — OPTIONAL Before Effective Date 5.2.72 short circuit current rating – the maximum available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected.

NOTE 7: Short circuit current rating for an electrical system is typically based on the analysis of short circuit ratings of the components within the system. See UL 508A and Related Information 2 of SEMI S22 for a methods which may be used to determine short circuit rating.

NOTICE: Paragraphs entitled “NOTE” are not an official part of this safety guideline and are not intended to modify or supersede the official safety guideline. These have been supplied by the committee to enhance the usage of the safety guideline. SEMI makes no warranties or representations as to the suitability of the guideline set forth herein for any particular application. The determination of the suitability of the guideline is solely the responsibility of the user. Users are cautioned to refer to manufacturer’s instructions, product labels, product data sheets, and other relevant literature respecting any materials mentioned herein. This guideline is subject to change without notice.

The user’s attention is called to the possibility that compliance with this guideline may require use of copyrighted material or of an invention covered by patent rights. By publication of this guideline, SEMI takes no position respecting the validity of any patent rights or copyrights asserted in connection with any item mentioned in this guideline. Users of this guideline are expressly advised that determination of any such patent rights or copyrights, and the risk of infringement of such rights, are entirely their own responsibility.

Line Item 1, Part 5b: Addition of the Delayed Revision Section to SEMI S22 Related to the definition of Short Circuit Current Rating.

Revision 004, April 15th, 2008 14 NOTICE: This Delayed Revisions Section contains material that has been balloted and approved by the SEMI Environmental Health and Safety Committee, but is not immediately effective. The provisions of this material are not an authoritative part of the document until their effective date. The main body of SEMI S22-0706 remains the authoritative version. Some or all of the provisions of revisions not yet in effect may be applied prior to the effective date, providing they do not conflict with portions of the authoritative version other than those that are to be revised or replaced as part of the deferred revision, and are labeled accordingly. NOTICE: Unless otherwise noted, all material to be added is underlined, and all material to be deleted is struck through. Note: Section, subsection, paragraph, note, table, and figure numbers that will be determined by their sequence in the document on the effective date are indicated by the character "x".

Dx-1 Revision of Note to the definition of Short Circuit Current Rating to Section 5 (Terminology) — OPTIONAL Before Effective Date 5.1.66 short circuit current rating — the maximum prospective available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected.

NOTE 12: Short circuit current rating for an electrical system is typically based on the analysis of short circuit current ratings of the components within the system. See UL 508A and Related Information 2 for a methods which may be used to determine short circuit current rating.

Line Item 1, Part 5c: Addition of the Delayed Revision Section to SEMI S26 Related to the definition of Short Circuit Current Rating.

NOTICE: This Delayed Revisions Section contains material that has been balloted and approved by the SEMI Environmental Health and Safety Committee, but is not immediately effective. The provisions of this material are not an authoritative part of the document until their effective date. The main body of SEMI S26-0308 remains the authoritative version. Some or all of the provisions of revisions not yet in effect may be applied prior to the effective date, providing they do not conflict with portions of the authoritative version other than those that are to be revised or replaced as part of the deferred revision, and are labeled accordingly. NOTICE: Unless otherwise noted, all material to be added is underlined, and all material to be deleted is struck through.

15 Note: Section, subsection, paragraph, note, table, and figure numbers that will be determined by their sequence in the document on the effective date are indicated by the character "x".

Dx-1 Revision of Note to the definition of Short Circuit Current Rating to Section 5 (Terminology) — OPTIONAL Before Effective Date

5.2.83 short circuit current rating — the maximum available current to which the system supply circuit is intended, by the system manufacturer, to be connected.

NOTE 7: Short circuit current rating for an electrical system is typically based on the analysis of short circuit current ratings of the components within the system. See UL 508A and Related Information 2 of SEMI S22 for a methods which may be used to determine short circuit current rating.

Revision 004, April 15th, 2008 16 Line Item 2, Part 1a: Revise definition of short circuit current in Section 5.2.72 of SEMI S2 to align with the definition in draft IEC 60204-33. Text to be removed is shown struck through; text to be added is shown underlined. Only the text that is struck through or underlined is proposed to be changed by this Line Item.

5.2.72 short circuit current rating – the maximum available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected maximum input current at which the short-circuit rating of each of the overcurrent protective devices in the equipment or its industrial control panel is at least equal to the prospective fault current at its point of connection.

Line Item 2, Part 1b: Add Notice to Section 5 indicating delayed implementation.

Line Item 2, Part 2a: Revise definition of short circuit current in Section 5.1.66 of SEMI S22 to align with the definition in draft IEC 60204-33. Text to be removed is shown struck through; text to be added is shown underlined. Only the text that is struck through or underlined is proposed to be changed by this Line Item.

5.1.66 short circuit current rating – the maximum prospective available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected maximum input current at which the short-circuit rating of each of the overcurrent protective devices in the equipment or its industrial control panel is at least equal to the prospective fault current at its point of connection.

Line Item 2, Part 2b: Add Notice to Section 5 indicating delayed implementation.

Line Item 2, Part 3a: Revise definition of short circuit current in Section 5.2.83 of SEMI S26 to align with the definition in draft IEC 60204-33. Text to be removed is shown struck through; text to be added is shown underlined. Only the text that is struck through or underlined is proposed to be changed by this Line Item.

5.2.83 short circuit current rating – the maximum available current to which the system supply circuit is intended, by the system manufacturer, to be connected maximum input current at which the short-circuit rating of each of the overcurrent protective devices in the equipment or its industrial control panel is at least equal to the prospective fault current at its point of connection.

17 Line Item 2, Part 3b: Add Notice to Section 5 indicating delayed implementation.

Line Item 2, Part 4a: Addition of the Delayed Revision Section to SEMI S2 Related to the definition of Short Circuit Current Rating.

5.2.72 short circuit current rating – the maximum available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected maximum input current at which the short-circuit rating of each of the overcurrent protective devices in the equipment or its industrial control panel is at least equal to the prospective fault current at its point of connection.

NOTE 7: Short circuit current rating for an electrical system is typically based on the analysis of short circuit ratings of the components within the system. See UL 508A for a method which may be used to determine short circuit rating.

The user’s attention is called to the possibility that compliance with this guideline may require use of copyrighted material or of an invention covered by patent rights. By publication of this guideline, SEMI takes no position respecting the validity of any patent rights or copyrights asserted in connection with any item mentioned in this guideline. Users of this guideline are expressly

Revision 004, April 15th, 2008 18 advised that determination of any such patent rights or copyrights, and the risk of infringement of such rights, are entirely their own responsibility.

Line Item 2, Part 4b: Addition of the Delayed Revision Section to SEMI S22 Related to the definition of Short Circuit Current Rating.

5.1.66 short circuit current rating – the maximum prospective available current to which an equipment supply circuit is intended, by the equipment manufacturer, to be connected maximum input current at which the short-circuit rating of each of the overcurrent protective devices in the equipment or its industrial control panel is at least equal to the prospective fault current at its point of connection.

NOTE 12: Short circuit current rating for an electrical system is typically based on the analysis of short circuit current ratings of the components within the system. See UL 508A for a method which may be used to determine short circuit current rating.

19 Line Item 2, Part 4c: Addition of the Delayed Revision Section to SEMI S26 Related to the definition of Short Circuit Current Rating.

5.2.83 short circuit current rating – the maximum available current to which the system supply circuit is intended, by the system manufacturer, to be connected maximum input current at which the short-circuit rating of each of the overcurrent protective devices in the equipment or its industrial control panel is at least equal to the prospective fault current at its point of connection.

NOTE 7: Short circuit current rating for an electrical system is typically based on the analysis of short circuit current ratings of the components within the system. See UL 508A for a method which may be used to determine short circuit current rating.

Revision 004, April 15th, 2008 20