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2011 NEC ROP CMP 5 . Elliot Rappaport Daleep Mohla . Total Proposals. Number of Proposals 324 Number of Panel Proposals 18 TIA 01 Accept 56 Accept in Part 06 Accept in Pr in Part 04 Accept in Principle 69 Reject 205 Redirected to other panels 02 .
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2011 NEC ROP CMP 5 • Elliot Rappaport • Daleep Mohla 2011 NEC ROP - CMP 5 Report to SCC 18
Total Proposals • Number of Proposals 324 • Number of Panel Proposals 18 • TIA 01 • Accept 56 • Accept in Part 06 • Accept in Pr in Part 04 • Accept in Principle 69 • Reject 205 • Redirected to other panels 02 2011 NEC ROP - CMP 5 Report to SCC 18
EEI Light and Power Task Force Proposals • 16 proposals by EEI to redefine Service cable and Service Conductors to Service Entrance Cable and Service Entrance Conductors , definition of Ground Fault etc 2011 NEC ROP - CMP 5 Report to SCC 18
Definitions • Proposal 5-10 Ground fault definition relocated to Article 100 • Proposal 5-13 • CMP 5 deleted the definition of Grounding conductor in place of correct term of Grounding Electrode Conductor. • Recommended formation of a TG of multiple panels to evaluate the impact of this change to other articles 2011 NEC ROP - CMP 5 Report to SCC 18
Color Coding of wires • 200.6 (A) & (B) • Rejected Proposal 5-36 to change color coding from #6 AWG to # 10 AWG 2011 NEC ROP - CMP 5 Report to SCC 18
High Voltage • CMP 503 Proposal 5- 51 a • Changed “ high voltage” used in Article 250 to “Over 1 kV” to remove inconsistency with other articles where over 600 Volts is used as high voltage 2011 NEC ROP - CMP 5 Report to SCC 18
Ground Detection Systems • Proposal 5-86 • Panel rejected the proposal for equipment for annunciation of ground detector system at a readily accessible location • Negative vote : The proposal should have been accepted in principle to ensure that a ground alarm is conveyed to an attended location for detection and mitigation purposes 2011 NEC ROP - CMP 5 Report to SCC 18
Ungrounded Systems Marking • CP 502 Proposal 5-86 a • Ungrounded systems to be marked at the source or at the first disconnecting means 2011 NEC ROP - CMP 5 Report to SCC 18
SSBJ • 5-102 • Introduces a new term Supply Side Bonding Jumper and acronym (SSBJ) in 250.30. • This is called Equipment Bonding Jumper in 2008 NEC 2011 NEC ROP - CMP 5 Report to SCC 18
Metal Underground water pipe • 5- 146 • 250.52(A)(1). • Last paragraph ( 5 feet rule) and Industrial exception have been relocated to new 250.68(C) because it pertains to usage of electrode. 2011 NEC ROP - CMP 5 Report to SCC 18
Industrial Exception • 5-148 • 250.52 (A)(1) Exception • Panel rejected the proposal to remove industrial exception 2011 NEC ROP - CMP 5 Report to SCC 18
Concrete Encased ElectrodesSCC 18:Do we need to comment? • 5-150 250.52 (A)(2) • Metal Frame of the Building or Structure. The metal frame of the building or structure that is connected to the earth by any of the following methods: • (At least one structural metal member that is in direct contact with the earth for 3.0m ( 10 ft) or more, with or without encasement • (2) The hold- down bolts securing the structural member are connected to a concrete encased electrode that complies with 250.52(A)(3)………….. • Other methods( using other electrodes, other approved methods have been deleted) 2011 NEC ROP - CMP 5 Report to SCC 18
Ground Rod SizeVote negative? • 5-168 250.52 (A)(5)(b) • Panel rejected the deletion of underlined text proposed by NEMA • Grounding electrodes of stainless steel and copper or zinc coated steel shall be at least 15.87 mm ( in.) in diameter, unless listed and not less than 12.70 mm (½ in.) in diameter. • Should NEC be establishing listing requirements? 2011 NEC ROP - CMP 5 Report to SCC 18
Supplemental Electrode Required • 5-169b 250.53(A) • A supplemental electrode is required where rod, pipe, or plate electrode is used • Exception: If a single rod, pipe , or plate electrode has a resistance of 25 ohms or less, the supplemental electrode shall not be required. • FYI : Proposal 5-176a deleted 250.60 which had reverse requirement (second electrode is required if one is above 25 ohms) 2011 NEC ROP - CMP 5 Report to SCC 18
Air Terminal changed to Strike Termination Device • 5-169b 250.53 (B); • 5-179 250.60; • 5-258 250.106 • Changed Air Terminal to Strike Termination Device to be consistent with NFPA 780 2011 NEC ROP - CMP 5 Report to SCC 18
Bonding JumpersNegative Vote or Affirmative comment? • 5-240 250.102 • 5-240 was Accepted in Principle by the panel and title of 250.102 (C) was changed to • “SSBJ on Supply Side of an Overcurrent Device” • See next slide for statement 2011 NEC ROP - CMP 5 Report to SCC 18
Bonding JumpersNegative Vote or Affirmative comment • Title reads “SSBJ on Supply Side of an Overcurrent Device”. If the acronym of SSBJ in 250.30(A)(2) is used, it will read “ Supply Side Bonding Jumper on the Supply side of Overcurrent Protection device. Can SSBJ term be used accurately if the bonding jumper is on the load side of the overcurrent protective device? • The title should read “Bonding Jumper on Supply side of Overcurrent device” • Section 250.102(C) uses the acronym “SSBJ” which is defined only once in 250.30(A)(2). 250.102(C) Use of the acronym will reduce usability until the acronym is in general use by the industry. This may take several Code cycles. Until then, the acronym as well as the full name should be used 2011 NEC ROP - CMP 5 Report to SCC 18
250.104 (B) 2008 NEC • B) Other Metal Piping. Where installed in or attached to a building or structure, a metal piping system(s), including gas piping, that is likely to become energized shall be bonded to the service equipment enclosure, the grounded conductor at the service, the grounding electrode conductor where of sufficient size, or the one or more grounding electrodes used. The bonding jumper(s) shall be sized in accordance with 250.122, using the rating of the circuit that is likely to energize the piping system(s). The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means. The points of attachment of the bonding jumper(s) shall be accessible 2011 NEC ROP - CMP 5 Report to SCC 18
CSST • 5-251 250.104 (B) TIA 941 • Panel rejected the proposal to require a split (B) into two parts for metal piping other than CSST and CSST and require minimum # 6AWG Copper for bonding of Corrugated Stainless Steel Tubing (CSST) and follow table 250.66 to prevent damage to CSST due to direct and indirect lightning strikes. • Proposal alos mentioned that this is required by all CSST manufacturers 2011 NEC ROP - CMP 5 Report to SCC 18
CSST • Panel statement mentioned that : • Not convinced that this will solve the problem as no test data or substantiation has been provide to support the claim. • Panel was made awate that at least one other manufacturer does not require larger than as required by current 250.104 • This is a product safety issue. • Not currently prohibited by National Electrical Code 2011 NEC ROP - CMP 5 Report to SCC 18
CSST TIA 941 • IEEE plans to vote negative on TIA 941 in support of the panel 2011 NEC ROP - CMP 5 Report to SCC 18
Luminaire GroundingDiscussion • 5-264 250.112 (J) Rejected by the panel 12-4 Submitter require all luminaires be provided with an equipment grounding conductor even for GFCI protected replavement luminaires exempted at present under 410.42 . • Submitter’s concern that a ground fault will energize the frame of the luminaire supplied by GFCI without an EGC and ground path will be provided by the person touching it. • Should we trust GFCI without EGC? 2011 NEC ROP - CMP 5 Report to SCC 18
EMT as an EGC?Negative vote by IEEE • 5-272 250.118 (4) • Panel rejected the proposal to delete EMT as an equipment grounding conductor and require a separate EGC within EMT. • Concern is the ground path depends on connector ( not threaded) and couplings • IEEE plans to vote against the panel action with the statement on the next slide 2011 NEC ROP - CMP 5 Report to SCC 18
EMT as an EGC?Negative vote by IEEE • It is regrettable that, after many years of proposals indicating that there is a real problem on roof tops, Code Panel 5 continues to use the same answer of “no technical substantiation”. There probably is none but there is evidence of real world issues of fittings coming apart and leaving equipment ungrounded. EMT can be installed easily without adequate tightening of fittings or fittings get loose . As a result, the raceway is adequate for installing conductors but inadequate as an equipment grounding conductor. This issue will not go away as evidenced by the proposal at every Code cycle. 2011 NEC ROP - CMP 5 Report to SCC 18
Table 250. 122 • 5-281 • Panel rejected proposal to replace table 250.122 based on overcurrent devices with a new table based on ungrounded conductor sizes as certain sizes of cables were not included • Concern cited is inability to parallel muticonductor UL listed cables that has a fixed size EGC since EGC has to be based on OCPD because following 250. 122 each cable requires a EGC based on the table 2011 NEC ROP - CMP 5 Report to SCC 18
EGC sizing in parallel cablepossiblenegative vote? Panel vote 10-6 • 5-287 250. 122 (A) • Panel rejected the proposal to add “including in parallel circuits” to 250.122(A) that does not require EGC to be larger than ungrounded conductor. • Concern cited by the submitter was a case where multiple 500 kcmil supplied by a 5000 A OCPD which requires 700 kcmil EGC ( larger than ungrounded conductors) 2011 NEC ROP - CMP 5 Report to SCC 18
Multigrounded system • Don Zipse proposals 5- 311 and 5- 312 on 250.184 (A)(1) and 250.184 C respectively were rejected by the panel. • Don proposed 250. 184 C be deleted. This allows systems to be multi grounded • Panel statement indicated no adequate substantiation has been provided to delete this “safe option” • IEEE plans to vote negative on 5-312 2011 NEC ROP - CMP 5 Report to SCC 18
5-313 250. 184 CNegative vote by IEEE • The Panel Statement is not correct. This proposal has been presented many times in the past for each Code cycle. Each time the Proposer presents additional substantiation of the hazards of the multigrounded system without repeating the previous substantiation. New Panel members are remiss if they do not seek out the previous substantiation which is pertinent to deciding how to address this issue. The Panel Statement is not correct in stating that the multigrounded neutral system is safe. This section was added in a previous Code cycle without substantiation except to state that it was permitted in the National Electric Safety Code used by the Utilities. Use by the Utilities is for the purpose of protecting the linemen and does not address the issue of ground currents that are hazardous to the public. 2011 NEC ROP - CMP 5 Report to SCC 18
Shielded Cable • 5-313 250.190 • Panel accepted in principle this proposal • Prohibits use of copper screen and ribbon shield to be used as EGC in solidly grounded systems. • Panel action has been sent to CMP 6 and 10 for comments 2011 NEC ROP - CMP 5 Report to SCC 18
Shielded Cable 250.190 C (2) • Shielded Cables • If the cable assembly is suitably rated for the ground fault current and is of the concentric neutral type, the shield conductor shall be permitted as the equipment grounding conductor. For solidly grounded systems, the cable copper screen or ribbon shield or combination of both shall not be used as equipment grounding conductor. 2011 NEC ROP - CMP 5 Report to SCC 18
Surge Arresters • 280.5 • Proposals 5-315 to 5- 319 • Listing requirement of Surge Arresters has been removed as no listed surge arresters are available 2011 NEC ROP - CMP 5 Report to SCC 18
Surge Protection Devices (SPD) • 5- 323 • Panel rejected a proposal to require a status indication to indicate device is energized and some indication that it is no longer effective or usable. • Panel Statement : It is a product safety issue> • Is it or shall we require? 2011 NEC ROP - CMP 5 Report to SCC 18
SPD Type 3 • 5- 324 285.25 Type 3 SPDs • Panel accepted ( 11-5) a proposal to add tagquirement for Type 3 SPD’s • Type 3 SPD connection shall be a minimum of 10 m (30 feet) of conductor distance from the service or separately derived system disconnect if the Type 3 SPD includes cautionary marking, tag, or instructions statement pertaining to 10 m( 30 ft) distance 2011 NEC ROP - CMP 5 Report to SCC 18