Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
Zhang Guoqing - I'm not sure where to begin to respond to the below, so I'll limit my responses to the following. 1) §1.4.11 is in §1.4, General conditions for test, and presents an assumption about the nature of telecommunications networks in general. For the purposes of this standard, is not intended to provide a reference requirement to other standards or to place a specific requirement on the output of a TNV circuit. 2) ETSI and other standards are welcome to reference 60950-1, but this does not always equate to a perfect mapping of 60950-1 into those other standards. 3) The maximum current a circuit is capable of delivering is not necessarily (and typically is not) into a load identical to the Norton equivalent output impedance of the source circuit. 4) TNV circuits output characteristics are evaluated in §2.3. 5) I was a member of the Canada/US BiNational Working Group (BNWG) when the requirement in §6.3 was developed and had input into TC 74 through the TC 74 Chair, who was also a member of the BNWG. The same is true for §1.4.11. 6) If you're interested in further reading, consider UL 1863, which was one of the references used to develop the 1.3 A limit. Regards, Peter Tarver -Original Message- From: Zhangguoqing (A) [mailto:zhangguoq...@huawei.com] Sent: Monday, September 16, 2013 19:05 To: Peter Tarver; EMC-PSTC@LISTSERV.IEEE.ORG Subject: 答复: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1 Dear Peter, Thanks for your reply. For this topic, my opinion is: --- --- --- --- --- --- --- - if it is declared and installed for power transmission, the power transmit / receive equipment will be installed by skilled person, and be installed in pairs. clause 6.3 should be the requirement for power transmit equipment, but 15VA should not be the requirement for power transmit equipment. so, the power distributed to and available from the TELECOMMUNICATION NETWORK will be larger than 15 VA. - if it is not declared and installed for power transmission, the power available from a TELECOMMUNICATION NETWORK is considered to be limited to 15 VA, and so the equipment connected to the TELECOMMUNICATION NETWORK ? does not need to comply with §4.6.4.3 ? does not need a fire enclosure for the connectors, per §4.7.2.2, 7th dashed paragraph ? does not need a fire enclosure for materials rated HB75 or HB40 less flammable (under specified conditions), per §4.7.2.2, 9th dashed paragraph, 2nd dotted subparagraph ? use the connector material exemption in §4.7.3.3, 3rd paragraph, 5th dashed subparagraph ? etc. --- --- --- --- --- --- --- But, in some ETSI standards, 15VA is a limit for power transmission equipment. The reason for this limit is interpreted as according to EN 60950-1 in those standards! For example, this sentence is extracted from clause 4.3 of ETSI TR 102 614 V1.1.1 (2010-06): 15 W is the limit according to EN 60950-1 [i.9] for the power on a telecommunication network and the A4 interface is be designed in order to limit the output current to a value that does not cause damage to the telecommunication wiring system due to overheating, under any load condition as required by the same EN 60950-1 [i.9]. The S/Pfilter should be dimensioned for the maximum current of 250 mA at 60 V. so, I am confused with this sentence. This email message is for the sole use of the intended recipient(s) and may contain confidential and/or privileged information. If you are not an intended recipient, you may not review, use, copy, disclose or distribute this message. If you received this message in error, please contact the sender by reply email and destroy all copies of the original message. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc.
Re: [PSES] 答复: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
From: Boštjan Glavič [mailto:bostjan.gla...@siq.si] Sent: Friday, September 13, 2013 21:21 To summarize, limit of 1.3A is applicable for CO equipment, and limit 15VA for subscriber units (analogue or ISDN phones, modems etc). This is simply not correct. Please see my post earlier in this thread. Regards, Peter Tarver This email message is for the sole use of the intended recipient(s) and may contain confidential and/or privileged information. If you are not an intended recipient, you may not review, use, copy, disclose or distribute this message. If you received this message in error, please contact the sender by reply email and destroy all copies of the original message. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
From: Zhangguoqing (A) Sent: Friday, September 13, 2013 17:57 If a transmit equipment can deliver 1.3A current into telecommunication network, then in the corresponding receive equipment (terminals), 1.3A current is available, do you think so? The 1.3 A limitation is under worst-case loading conditions, and is not the normal operating current. For any loading condition up to and including short-circuit, the output current available from the source cannot exceed 1.3 A. This concept is not unlike the LPS current limits in §2.5 in that the intent is to not create a risk of fire in certain common premises wiring and connection devices. My question is why the standard states the transmit equipment can deliver 1.3A (max.), but at the same time it states the power available from a TELECOMMUNICATION NETWORK is limited to 15 VA? The 15 VA assumption in §1.4.11 is assumed by definition. It is the assumed power available from an unknown/generic telecommunications network, which may come from a PBX, a central office, a key system or other equipment, which the equipment under evaluation has no specific knowledge of. Because this is assumed by definition it is not a requirement that applies to equipment outputs in IEC 60950-1. These requirements are contained elsewhere in the standard. If you connect a terminal device to a telecommunications network, the anticipated power available from the telecommunications network is 15 VA. By defining this power limitation, for the purposes of this standard, doubt about what the connection is like is ameliorated. For example, if I were to connect a POTS telephone or other network (nonPoE) device to a telecommunications network, the POTS device: • does not need to comply with §4.6.4.3 • does not need a fire enclosure for the connectors, per §4.7.2.2, 7th dashed paragraph • does not need a fire enclosure for materials rated HB75 or HB40 less flammable (under specified conditions), per §4.7.2.2, 9th dashed paragraph, 2nd dotted subparagraph • use the connector material exemption in §4.7.3.3, 3rd paragraph, 5th dashed subparagraph • etc. The same exceptions/exemptions can apply to those portions of a fax machine, computer, answering machine and the like, where there are no extenuating circumstances caused by other circuits/components in the vicinity of the TNV circuit. Regards, Peter Tarver This email message is for the sole use of the intended recipient(s) and may contain confidential and/or privileged information. If you are not an intended recipient, you may not review, use, copy, disclose or distribute this message. If you received this message in error, please contact the sender by reply email and destroy all copies of the original message. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
[PSES] 答复: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
Dear Peter, Thanks for your reply. For this topic, my opinion is: - - if it is declared and installed for power transmission, the power transmit / receive equipment will be installed by skilled person, and be installed in pairs. clause 6.3 should be the requirement for power transmit equipment, but 15VA should not be the requirement for power transmit equipment. so, the power distributed to and available from the TELECOMMUNICATION NETWORK will be larger than 15 VA. - if it is not declared and installed for power transmission, the power available from a TELECOMMUNICATION NETWORK is considered to be limited to 15 VA, and so the equipment connected to the TELECOMMUNICATION NETWORK ? does not need to comply with §4.6.4.3 ? does not need a fire enclosure for the connectors, per §4.7.2.2, 7th dashed paragraph ? does not need a fire enclosure for materials rated HB75 or HB40 less flammable (under specified conditions), per §4.7.2.2, 9th dashed paragraph, 2nd dotted subparagraph ? use the connector material exemption in §4.7.3.3, 3rd paragraph, 5th dashed subparagraph ? etc. - But, in some ETSI standards, 15VA is a limit for power transmission equipment. The reason for this limit is interpreted as according to EN 60950-1 in those standards! For example, this sentence is extracted from clause 4.3 of ETSI TR 102 614 V1.1.1 (2010-06): 15 W is the limit according to EN 60950-1 [i.9] for the power on a telecommunication network and the A4 interface is be designed in order to limit the output current to a value that does not cause damage to the telecommunication wiring system due to overheating, under any load condition as required by the same EN 60950-1 [i.9]. The S/Pfilter should be dimensioned for the maximum current of 250 mA at 60 V. so, I am confused with this sentence. Zhang Guoqing Huawei Technologies Co., Ltd. Bantian, Longgang District,Shenzhen 518129, P.R.China Tel: +86-13686493636 Email: zhangguoq...@huawei.com http://www.huawei.com -邮件原件- 发件人: Peter Tarver [mailto:ptar...@enphaseenergy.com] 发送时间: 2013年9月17日 4:58 收件人: EMC-PSTC@LISTSERV.IEEE.ORG 主题: Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1 From: Zhangguoqing (A) Sent: Friday, September 13, 2013 17:57 If a transmit equipment can deliver 1.3A current into telecommunication network, then in the corresponding receive equipment (terminals), 1.3A current is available, do you think so? The 1.3 A limitation is under worst-case loading conditions, and is not the normal operating current. For any loading condition up to and including short-circuit, the output current available from the source cannot exceed 1.3 A. This concept is not unlike the LPS current limits in §2.5 in that the intent is to not create a risk of fire in certain common premises wiring and connection devices. My question is why the standard states the transmit equipment can deliver 1.3A (max.), but at the same time it states the power available from a TELECOMMUNICATION NETWORK is limited to 15 VA? The 15 VA assumption in §1.4.11 is assumed by definition. It is the assumed power available from an unknown/generic telecommunications network, which may come from a PBX, a central office, a key system or other equipment, which the equipment under evaluation has no specific knowledge of. Because this is assumed by definition it is not a requirement that applies to equipment outputs in IEC 60950-1. These requirements are contained elsewhere in the standard. If you connect a terminal device to a telecommunications network, the anticipated power available from the telecommunications network is 15 VA. By defining this power limitation, for the purposes of this standard, doubt about what the connection is like is ameliorated. For example, if I were to connect a POTS telephone or other network (nonPoE) device to a telecommunications network, the POTS device: ? does not need to comply with §4.6.4.3 ? does not need a fire enclosure for the connectors, per §4.7.2.2, 7th dashed paragraph ? does not need a fire enclosure for materials rated HB75 or HB40 less flammable (under specified conditions), per §4.7.2.2, 9th dashed paragraph, 2nd dotted
Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
-Original Message- From: Zhangguoqing (A) [mailto:zhangguoq...@huawei.com] Sent: Wednesday, September 11, 2013 05:39 My question is , if a equipment intends to provide power over the telecommunication wiring system, the current and the power should be controlled at the same time? or, only the current should be controlled? Zhang Guoqing - §1.4.11 is the assumed power available *from* a telecommunications network to connected equipment (terminals). A POTS device, for example, with no other power sources can be considered to be supplied by a 15 VA power limited source. This plays nicely with the 15 VA limits you'll find in the fire enclosure and internal wiring requirements. §6.3 relates to current generated by equipment and *delivered into* a telecommunications network under worst-case loading conditions. The intent is to protect wiring and wiring devices typical in telecommunications networks, in particular modular plugs/jacks, line cords and the like. Regards, Peter Tarver This email message is for the sole use of the intended recipient(s) and may contain confidential and/or privileged information. If you are not an intended recipient, you may not review, use, copy, disclose or distribute this message. If you received this message in error, please contact the sender by reply email and destroy all copies of the original message. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
[PSES] 答复: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
Dear Peter, Thank you for your reply. If a transmit equipment can deliver 1.3A current into telecommunication network, then in the corresponding receive equipment (terminals), 1.3A current is available, do you think so? My question is why the standard states the transmit equipment can deliver 1.3A (max.), but at the same time it states the power available from a TELECOMMUNICATION NETWORK is limited to 15 VA? Zhang guoqing -邮件原件- 发件人: Peter Tarver [mailto:ptar...@enphaseenergy.com] 发送时间: 2013年9月14日 7:27 收件人: EMC-PSTC@LISTSERV.IEEE.ORG 主题: Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1 -Original Message- From: Zhangguoqing (A) [mailto:zhangguoq...@huawei.com] Sent: Wednesday, September 11, 2013 05:39 My question is , if a equipment intends to provide power over the telecommunication wiring system, the current and the power should be controlled at the same time? or, only the current should be controlled? Zhang Guoqing - §1.4.11 is the assumed power available *from* a telecommunications network to connected equipment (terminals). A POTS device, for example, with no other power sources can be considered to be supplied by a 15 VA power limited source. This plays nicely with the 15 VA limits you'll find in the fire enclosure and internal wiring requirements. §6.3 relates to current generated by equipment and *delivered into* a telecommunications network under worst-case loading conditions. The intent is to protect wiring and wiring devices typical in telecommunications networks, in particular modular plugs/jacks, line cords and the like. Regards, Peter Tarver This email message is for the sole use of the intended recipient(s) and may contain confidential and/or privileged information. If you are not an intended recipient, you may not review, use, copy, disclose or distribute this message. If you received this message in error, please contact the sender by reply email and destroy all copies of the original message. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
Re: [PSES] 答复: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
Dear Zhang, As fair as I know, there are many old twisted pair wirings around the world without standardized cross-sectional are. Therefore they checked it and set maximum limit from central office to 1.3A. However on the subscriber side you will never get more than few 10mA (usually 20-40mA). This is enough for analogue telephone to operate. Therefore you will never exceed 15W on subscriber side. To summarize, limit of 1.3A is applicable for CO equipment, and limit 15VA for subscriber units (analogue or ISDN phones, modems etc). Please consider this is not applicable for Power over Ethernet. This is local network and not for public telecommunication network. Best regards, Bostjan On 14. sep. 2013, at 02:57, Zhangguoqing (A) zhangguoq...@huawei.com wrote: Dear Peter, Thank you for your reply. If a transmit equipment can deliver 1.3A current into telecommunication network, then in the corresponding receive equipment (terminals), 1.3A current is available, do you think so? My question is why the standard states the transmit equipment can deliver 1.3A (max.), but at the same time it states the power available from a TELECOMMUNICATION NETWORK is limited to 15 VA? Zhang guoqing -邮件原件- 发件人: Peter Tarver [mailto:ptar...@enphaseenergy.com] 发送时间: 2013年9月14日 7:27 收件人: EMC-PSTC@LISTSERV.IEEE.ORG 主题: Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1 -Original Message- From: Zhangguoqing (A) [mailto:zhangguoq...@huawei.com] Sent: Wednesday, September 11, 2013 05:39 My question is , if a equipment intends to provide power over the telecommunication wiring system, the current and the power should be controlled at the same time? or, only the current should be controlled? Zhang Guoqing - §1.4.11 is the assumed power available *from* a telecommunications network to connected equipment (terminals). A POTS device, for example, with no other power sources can be considered to be supplied by a 15 VA power limited source. This plays nicely with the 15 VA limits you'll find in the fire enclosure and internal wiring requirements. §6.3 relates to current generated by equipment and *delivered into* a telecommunications network under worst-case loading conditions. The intent is to protect wiring and wiring devices typical in telecommunications networks, in particular modular plugs/jacks, line cords and the like. Regards, Peter Tarver This email message is for the sole use of the intended recipient(s) and may contain confidential and/or privileged information. If you are not an intended recipient, you may not review, use, copy, disclose or distribute this message. If you received this message in error, please contact the sender by reply email and destroy all copies of the original message. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the
[PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
Hi, I have a question on clause 6.3 and clause 1.4.11 of IEC60950-1. 6.3 Protection of the telecommunication wiring system from overheating Equipment intended to provide power over the telecommunication wiring system to remote equipment shall limit the output current to a value that does not cause damage to the telecommunication wiring system, due to overheating, under any external load condition. The maximum continuous current from equipment shall not exceed a current limit that is suitable for the minimum wire gauge specified in the equipment installation instructions. The current limit is 1,3 A if such wiring is not specified. NOTE 2 The minimum wire diameter normally used in telecommunication wiring is 0,4 mm, for which the maximum continuous current for a multipair cable is 1,3 A. 1.4.11 Power from a telecommunication network For the purpose of this standard, the power available from a TELECOMMUNICATION NETWORK is considered to be limited to 15 VA. My question is , if a equipment intends to provide power over the telecommunication wiring system, the current and the power should be controlled at the same time? or, only the current should be controlled? Best regards, Zhang Guoqing - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
In message 7d25799235e00f4c9b04eca410c1c5bf8f0ba...@szxema502-mbx.china.huawei.com , dated Wed, 11 Sep 2013, Zhangguoqing (A) zhangguoq...@huawei.com writes: 6.3 Protection of the telecommunication wiring system from overheating Equipment intended to provide power over the telecommunication wiring system to remote equipment shall limit the output current to a value that does not cause damage to the telecommunication wiring system, due to overheating, under any external load condition. The maximum continuous current from equipment shall not exceed a current limit that is suitable for the minimum wire gauge specified in the equipment installation instructions. The current limit is 1,3 A if such wiring is not specified. NOTE 2 The minimum wire diameter normally used in telecommunication wiring is 0,4 mm, for which the maximum continuous current for a multipair cable is 1,3 A. 1.4.11 Power from a telecommunication network For the purpose of this standard, the power available from a TELECOMMUNICATION NETWORK is considered to be limited to 15 VA. My question is , if a equipment intends to provide power over the telecommunication wiring system, the current and the power should be controlled at the same time? or, only the current should be controlled? 1.4.11 is not a requirement, it is an assumption. Why it is stated, and why it is included under General conditions for tests are questions that the authors of the text should address. Unless a 'creative' interpretation of 1.4.11 indicates otherwise, I suggest that 1.4.11 has no effect on 6.3 and you need to limit only the current. -- OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk If dictionaries were correct, we would only need one, because they would all give the same information. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1
Thanks for John's reply The contents of clause 6.3 and 1.4.11 of IEC60950-1 are moved to IEC60368-1 1st edition 6.2.2.4 PS1 PS1 is a circuit where the power source, (see Figure 40) measured according to 6.2.2, does not exceed: �C 500 W measured during the first 3 s; and �C 15 W measured after 3 s. For the purpose of this standard, the power available from external circuits described in Table 16, ID numbers 11, 12, 13 and 14, are considered to be PS1. 6.5.4 Requirements for interconnection to building wiring. External paired conductor cable circuits, such as those described in Table 16, ID numbers 11, 12, 13 and 14 having a minimum wire diameter of 0,4 mm, shall have the current limited to 1,3 A. Please tell me if you know the current requirement and power requirement when a equipment intends to provide power over the telecommunication wiring system. Zhang guoqing -邮件原件- 发件人: John Woodgate [mailto:j...@jmwa.demon.co.uk] 发送时间: 2013年9月11日 22:50 收件人: EMC-PSTC@LISTSERV.IEEE.ORG 主题: Re: [PSES] question on clause 6.3 and 1.4.11 of IEC60950-1 In message 7d25799235e00f4c9b04eca410c1c5bf8f0ba...@szxema502-mbx.china.huawei.com , dated Wed, 11 Sep 2013, Zhangguoqing (A) zhangguoq...@huawei.com writes: 6.3 Protection of the telecommunication wiring system from overheating Equipment intended to provide power over the telecommunication wiring system to remote equipment shall limit the output current to a value that does not cause damage to the telecommunication wiring system, due to overheating, under any external load condition. The maximum continuous current from equipment shall not exceed a current limit that is suitable for the minimum wire gauge specified in the equipment installation instructions. The current limit is 1,3 A if such wiring is not specified. NOTE 2 The minimum wire diameter normally used in telecommunication wiring is 0,4 mm, for which the maximum continuous current for a multipair cable is 1,3 A. 1.4.11 Power from a telecommunication network For the purpose of this standard, the power available from a TELECOMMUNICATION NETWORK is considered to be limited to 15 VA. My question is , if a equipment intends to provide power over the telecommunication wiring system, the current and the power should be controlled at the same time? or, only the current should be controlled? 1.4.11 is not a requirement, it is an assumption. Why it is stated, and why it is included under General conditions for tests are questions that the authors of the text should address. Unless a 'creative' interpretation of 1.4.11 indicates otherwise, I suggest that 1.4.11 has no effect on 6.3 and you need to limit only the current. -- OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk If dictionaries were correct, we would only need one, because they would all give the same information. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to emc-p...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@radiusnorth.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: dhe...@gmail.com
