RE: current carrying conductors
The following is from a separate e-mail I sent to Richard Stone that I though the rest of the group might find interest in. In this e-mail exchange, the US NEC was referenced and so the following is based on the US NEC. In your post, you did not specify whether the conductors were a part of the supply source or internal to the equipment. However, based on your described application (use of ring lugs) and that you were claiming the No. 6 AWG conductor is good for 63A, it seemed evident that these weren't supply conductors. The final judge of the suitability, then, is the wire insulation for the additional temperature the wire will see. If these _are_ supply conductors, both paralleled No. 10 AWG and a single No. 6 AWG are too small and you'll need to revisit the NEC to find the appropriate size and temperature rating. Best case, per NEC Table 310-16 for 60C building wire: No. 10 AWG, 60C wire is good for maximum 30A and No. 6AWG is good for 55A. Any increases in in ampacity must come from using a more specific and tightly controlled wiring systems or increases in conductor temperature rating. Your reference to NEC 310-4 must be to Exceptions No. 2, 3 or 4, but this could be a misuse of those Exceptions, unless you meet all of the criteria in the applicable exception. > -Original Message- > From: Peter Tarver > Sent: Friday, August 17, 2001 9:14 AM > > Yes. > > Regards, > > Peter L. Tarver, PE > Product Safety Manager > Sanmina Homologation Services > peter.tar...@sanmina.com > > > -Original Message- > > From: owner-emc-p...@majordomo.ieee.org > > [mailto:owner-emc-p...@majordomo.ieee.org]On > > Behalf Of Stone, Richard A > > (Richard) > > > > Group, > > > > can you substitute one large wire 6 awg. > > handlles 63 amps. max ) > > for two smaller wires ( 10 awg. carries 32 amps. > > max. ) in Parallel. > > They would 1/2 the current and disperse heat better. > > > > The accepting screw terminal would allow for > > proper threading and tightness > > of connection. > > since you would have 2 ring lugs on one terninal > > instead of two. > > > > thank you, > > Richard, --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: current carrying conductors
Hi Richard: A number of good comments have been made. I'm not sure anyone covered the fact that two wires make a bundle, and therefore each single in that bundle must be derated. So, a single 10 AWG is good for 32 amps at 20 C. But, two 10 AWG wires in the same bundle are only good for 31 amps each at 20 C. Here's a caculator that might be of interest, but use cautiously as the calculator may not apply to your situation: http://www.geocities.com/CapeCanaveral/Lab/9643/awg.htm Best regards, Rich --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: current carrying conductors
According to the Belden wire table, 10awg carrying 32 amps will produce a 35C rise above ambient. And according to them, the bundling factor is 1.0 for 1, 2, or 3 bundled wires. If you're qualifying anything up around 40C high temp, your wire's going to be 75C. 5C doesn't give you much overhead for 80C rated wire. So, you might want to think long and hard about using 80C rated wire for such an application. IMO, you'd have to start with a minimum 105C rated wire. 8awg at 32 amps looks more like 23C rise above ambient. - Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
RE: current carrying conductors
Richard, The larger single wire, with appropriate ring lug, is actually the preferred construction. The two wire method is used in cases where something else in the system, such as a multi-wire connector, will only accept the smaller gauge wire. In that case each ring lug MUST be secured with its own star washer and nut. The stack up would be: Ring lug #1, star washer, nut, ring lug #2, star washer, nut. The screw or stud must be long enough for the top nut to have full thread engagement. Hope this is of help. Scott Lacey -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Stone, Richard A (Richard) Sent: Friday, August 17, 2001 9:01 AM To: emc-p...@majordomo.ieee.org Subject: current carrying conductors Group, can you substitute one large wire 6 awg. ( handlles 63 amps. max ) for two smaller wires ( 10 awg. carries 32 amps. max. ) in Parallel. They would 1/2 the current and disperse heat better. The accepting screw terminal would allow for proper threading and tightness of connection. since you would have 2 ring lugs on one terninal instead of two. thank you, Richard, --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall," --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
RE: current carrying conductors
Yes. Regards, Peter L. Tarver, PE Product Safety Manager Sanmina Homologation Services peter.tar...@sanmina.com > -Original Message- > From: owner-emc-p...@majordomo.ieee.org > [mailto:owner-emc-p...@majordomo.ieee.org]On > Behalf Of Stone, Richard A > (Richard) > > Group, > > can you substitute one large wire 6 awg. ( > handlles 63 amps. max ) > for two smaller wires ( 10 awg. carries 32 amps. > max. ) in Parallel. > They would 1/2 the current and disperse heat better. > > The accepting screw terminal would allow for > proper threading and tightness > of connection. > since you would have 2 ring lugs on one terninal > instead of two. > > thank you, > Richard, > --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: current carrying conductors
As a quick and simple answer, No. In a single fault condition, one cable becomes lose / detached. The reaming 32 amp capable see the full 63 amps. The result smoke, flame, etc. Expressly forbidden in some standards and knocked out by others under the single fault conditions. Only way to do this is to fuse each cable individually to 32 amps. Then it might be allowed depending on the exact configuration of the circuit. "Stone, Richard A (Richard)" wrote: > Group, > > can you substitute one large wire 6 awg. ( handlles 63 amps. max ) > for two smaller wires ( 10 awg. carries 32 amps. max. ) in Parallel. > They would 1/2 the current and disperse heat better. > > The accepting screw terminal would allow for proper threading and tightness > of connection. > since you would have 2 ring lugs on one terninal instead of two. > > thank you, > Richard, > > --- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson:pstc_ad...@garretson.org > Dave Healddavehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://www.rcic.com/ click on "Virtual Conference Hall," -- Andrew Carson - Product Safety Engineer, Xyratex, UK Phone: +44 (0)23 9249 6855 Fax: +44 (0)23 9249 6014 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: current carrying conductors
What happen, if one of these wire looses? Sérgio Rocha Loures Siemens Ltda. - Brazil Supply Chain - Quality and Engineering IC SC QE L Tel: +55 41 341-5755 Fax: +55 41 341-5058 E-mail: sergioro...@siemens.com.br >>> "Stone, Richard A (Richard)" 17/08/01 10:01 >>> Group, can you substitute one large wire 6 awg. ( handlles 63 amps. max ) for two smaller wires ( 10 awg. carries 32 amps. max. ) in Parallel. They would 1/2 the current and disperse heat better. The accepting screw terminal would allow for proper threading and tightness of connection. since you would have 2 ring lugs on one terninal instead of two. thank you, Richard, --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall," --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"