Re: [PSES] Min size of double insulation symbol relaxed
There are no U.S. national differences regarding the size of the double
insulation symbol in UL 60065, UL 60950-1 or UL 62368-1.
In many cases, Underwriters Laboratories (UL) is more flexible about the size
of marking that required by other standards agencies. For example, UL has
historically not placed a minimum size on the UL Listing mark. Their guidelines
even state when the mark is reduced below a specified size, the "registered
trademark" symbol is to be removed as it would be too small to be legible. That
being said, their label review process reserves the right to reject marking as
being too small to be reasonably legible.
It is possible that another country may have a national difference regarding
the symbol, but I am unaware of it and I personally have not had marking
rejected on one of my products due to the double insulation symbol being too
small.
Ted Eckert
Microsoft Corporation
The opinions expressed are my own and do not necessarily reflect those of my
employer, National Certification Bodies or the Fraternal Order of Class II
Product Labeling Specialists.
-Original Message-
From: John Woodgate [mailto:jmw1...@btinternet.com]
Sent: Friday, June 2, 2017 8:02 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Min size of double insulation symbol relaxed
I believe UL adds 'Special National Conditions' or something to the IEC
standards it adopts, just as Europe adds 'Common Modifications'.
With best wishes DESIGN IT IN! OOO – Own Opinions Only
https://na01.safelinks.protection.outlook.com/?url=www.jmwa.demon.co.uk&data=02%7C01%7Cted.eckert%40microsoft.com%7C97c9a2ff182e4e7a8bec08d4a9c85d3c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636320125403340378&sdata=WEyHQjkkjIQQHBFpJqMcpDoj3%2BILX4R9lKDMSB%2BjQ4k%3D&reserved=0
J M Woodgate and Associates Rayleigh England
Sylvae in aeternum manent.
-Original Message-
From: Scott Xe [mailto:scott...@gmail.com]
Sent: 02 June 2017 15:17
To: John Woodgate ; EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Min size of double insulation symbol relaxed
Hi John,
No, I did not. As far as I remember, UL adopts/harmonises IEC standard in last
10-15 years. This requirement appears as early as 20 years ago.
However, I just checked UL 60065 and 60950-1 without the requirement.
Thanks and regards,
Scott
On 2/6/2017, 3:11 AM, "John Woodgate" wrote:
Did you look at the UL versions of these standards as well as the IEC
versions?
With best wishes DESIGN IT IN! OOO – Own Opinions Only
https://na01.safelinks.protection.outlook.com/?url=www.jmwa.demon.co.uk&data=02%7C01%7Cted.eckert%40microsoft.com%7C97c9a2ff182e4e7a8bec08d4a9c85d3c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636320125403340378&sdata=WEyHQjkkjIQQHBFpJqMcpDoj3%2BILX4R9lKDMSB%2BjQ4k%3D&reserved=0
J M Woodgate and Associates Rayleigh England
Sylvae in aeternum manent.
-Original Message-
From: Scott Xe [mailto:scott...@gmail.com]
Sent: 01 June 2017 17:19
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Min size of double insulation symbol relaxed
Hi Peter,
Thanks for your advice! I read the previous 60056/60950-1/60335-1
standards back to 199x and still could not trace the following requirements.
The dimensions of the symbol for Class II construction shall be such that
the length of the sides of the outer square is about twice the length of the
sides of the inner square.
The length of the sides of the outer square shall not be less than 5mm,
unless the largest dimension of the appliance does not exceed 15cm, in which
case the dimensions of the symbol may be reduced, but the length of the sides
of the outer square shall not be less than 3mm.
I am unable to recall the originate of this requirement and suspect if it
comes from the safety standards. For the time being, I have just to refer to
the latest requirements in safety standards without above requirement.
Regards,
Scott
On 1/6/2017, 12:38 AM, "Peter Tarver" wrote:
Scott -
The CE mark size is mentioned in RED, but not the double insulation
symbol. The LVD implicitly defers to the CE Marking Directive for size.
IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to
refer to the standard used for the product bearing the Symbol 5172 for the
answer.
Peter Tarver
> -Original Message-
> From: Scott Xe
> Sent: Wednesday, May 31, 2017 08:55
>
> Is the minimum size of 5 mm relaxed to the legible reading
> in LVD and RED? Where and when does it introduce?
The information contained in this message may be privileged and
confidential. It is intended to be read only by the individual or entity to
whom i
Re: [PSES] Min size of double insulation symbol relaxed
I believe UL adds 'Special National Conditions' or something to the IEC
standards it adopts, just as Europe adds 'Common Modifications'.
With best wishes DESIGN IT IN! OOO – Own Opinions Only
www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England
Sylvae in aeternum manent.
-Original Message-
From: Scott Xe [mailto:scott...@gmail.com]
Sent: 02 June 2017 15:17
To: John Woodgate ; EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Min size of double insulation symbol relaxed
Hi John,
No, I did not. As far as I remember, UL adopts/harmonises IEC standard in last
10-15 years. This requirement appears as early as 20 years ago.
However, I just checked UL 60065 and 60950-1 without the requirement.
Thanks and regards,
Scott
On 2/6/2017, 3:11 AM, "John Woodgate" wrote:
Did you look at the UL versions of these standards as well as the IEC
versions?
With best wishes DESIGN IT IN! OOO – Own Opinions Only
www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England
Sylvae in aeternum manent.
-Original Message-
From: Scott Xe [mailto:scott...@gmail.com]
Sent: 01 June 2017 17:19
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Min size of double insulation symbol relaxed
Hi Peter,
Thanks for your advice! I read the previous 60056/60950-1/60335-1
standards back to 199x and still could not trace the following requirements.
The dimensions of the symbol for Class II construction shall be such that
the length of the sides of the outer square is about twice the length of the
sides of the inner square.
The length of the sides of the outer square shall not be less than 5mm,
unless the largest dimension of the appliance does not exceed 15cm, in which
case the dimensions of the symbol may be reduced, but the length of the sides
of the outer square shall not be less than 3mm.
I am unable to recall the originate of this requirement and suspect if it
comes from the safety standards. For the time being, I have just to refer to
the latest requirements in safety standards without above requirement.
Regards,
Scott
On 1/6/2017, 12:38 AM, "Peter Tarver" wrote:
Scott -
The CE mark size is mentioned in RED, but not the double insulation
symbol. The LVD implicitly defers to the CE Marking Directive for size.
IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to
refer to the standard used for the product bearing the Symbol 5172 for the
answer.
Peter Tarver
> -Original Message-
> From: Scott Xe
> Sent: Wednesday, May 31, 2017 08:55
>
> Is the minimum size of 5 mm relaxed to the legible reading
> in LVD and RED? Where and when does it introduce?
The information contained in this message may be privileged and
confidential. It is intended to be read only by the individual or entity to
whom it is addressed or by their designee. If the reader of this message is not
the intended recipient, you are on notice that any distribution of this
message, in any form, is strictly prohibited. If you have received this message
in error, please immediately notify the sender and delete or destroy any copy
of this message!
-
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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
All emc-pstc postings are archived and searchable on the web at:
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Attachments are not permitted but the IEEE PSES Online Communities site at
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formats), large files, etc.
Website
Re: [PSES] Min size of double insulation symbol relaxed
Hi John, No, I did not. As far as I remember, UL adopts/harmonises IEC standard in last 10-15 years. This requirement appears as early as 20 years ago. However, I just checked UL 60065 and 60950-1 without the requirement. Thanks and regards, Scott On 2/6/2017, 3:11 AM, "John Woodgate" wrote: Did you look at the UL versions of these standards as well as the IEC versions? With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England Sylvae in aeternum manent. -Original Message- From: Scott Xe [mailto:scott...@gmail.com] Sent: 01 June 2017 17:19 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Min size of double insulation symbol relaxed Hi Peter, Thanks for your advice! I read the previous 60056/60950-1/60335-1 standards back to 199x and still could not trace the following requirements. The dimensions of the symbol for Class II construction shall be such that the length of the sides of the outer square is about twice the length of the sides of the inner square. The length of the sides of the outer square shall not be less than 5mm, unless the largest dimension of the appliance does not exceed 15cm, in which case the dimensions of the symbol may be reduced, but the length of the sides of the outer square shall not be less than 3mm. I am unable to recall the originate of this requirement and suspect if it comes from the safety standards. For the time being, I have just to refer to the latest requirements in safety standards without above requirement. Regards, Scott On 1/6/2017, 12:38 AM, "Peter Tarver" wrote: Scott - The CE mark size is mentioned in RED, but not the double insulation symbol. The LVD implicitly defers to the CE Marking Directive for size. IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to refer to the standard used for the product bearing the Symbol 5172 for the answer. Peter Tarver > -Original Message- > From: Scott Xe > Sent: Wednesday, May 31, 2017 08:55 > > Is the minimum size of 5 mm relaxed to the legible reading > in LVD and RED? Where and when does it introduce? The information contained in this message may be privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete or destroy any copy of this 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To p
Re: [PSES] Min size of double insulation symbol relaxed
Hi Ted, Appreciate your useful info!! The standard does state the exact requirement. However, I believe it may not be come from this standard as the LED module was not yet commonly available. In addition, I do not understand how the requirement of a double insulation symbol is exclusive for LED module, not all other products meeting the requirement. Thanks and regards, Scott From: Ted Eckert Date: Friday, 2 June 2017 at 1:59 AM To: Scott Xe , "EMC-PSTC@LISTSERV.IEEE.ORG" Subject: RE: [PSES] Min size of double insulation symbol relaxed Hello Scott, I believe that there are some product specific standards with the dimensional requirement you mention. IEC 61347-2-13:2009 Annex I section I.4 includes the text you reference. However, this only applies to electronic controlgear for LED modules, not necessarily for other products. This is just the first example I found, and I only found it because a draft SASO adoption is available here and it was indexed by various Internet search engines (I’m not sure how IEC copyright licenses are handled in Saudi Arabia.) Ted Eckert Microsoft Corporation The opinions expressed are my own and do not necessarily reflect those of my employer. -Original Message- From: Scott Xe [mailto:scott...@gmail.com] Sent: Thursday, June 1, 2017 9:19 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Min size of double insulation symbol relaxed Hi Peter, Thanks for your advice! I read the previous 60056/60950-1/60335-1 standards back to 199x and still could not trace the following requirements. The dimensions of the symbol for Class II construction shall be such that the length of the sides of the outer square is about twice the length of the sides of the inner square. The length of the sides of the outer square shall not be less than 5mm, unless the largest dimension of the appliance does not exceed 15cm, in which case the dimensions of the symbol may be reduced, but the length of the sides of the outer square shall not be less than 3mm. I am unable to recall the originate of this requirement and suspect if it comes from the safety standards. For the time being, I have just to refer to the latest requirements in safety standards without above requirement. Regards, Scott On 1/6/2017, 12:38 AM, "Peter Tarver" wrote: Scott - The CE mark size is mentioned in RED, but not the double insulation symbol. The LVD implicitly defers to the CE Marking Directive for size. IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to refer to the standard used for the product bearing the Symbol 5172 for the answer. Peter Tarver > -Original Message- > From: Scott Xe > Sent: Wednesday, May 31, 2017 08:55 > > Is the minimum size of 5 mm relaxed to the legible reading > in LVD and RED? Where and when does it introduce? The information contained in this message may be privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete or destroy any copy of this 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 All emc-pstc postings are archived and searchable on the web at: https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2Femc-pstc.html&data=02%7C01%7Cted.eckert%40microsoft.com%7C128a6cf65f404a6b202008d4a90a008c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636319307807904541&sdata=heJOQDDEYexARH9hPpmAy9soihfiXtzFMkBwdW3zmxM%3D&reserved=0 Attachments are not permitted but the IEEE PSES Online Communities site at https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fproduct-compliance.oc.ieee.org%2F&data=02%7C01%7Cted.eckert%40microsoft.com%7C128a6cf65f404a6b202008d4a90a008c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636319307807914554&sdata=%2FFhm9xBDEDZoQ4BADuWbs%2FyATDcHIjcDwwTP4C3znLo%3D&reserved=0 can be used for graphics (in well-used formats), large files, etc. Website: https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2F&data=02%7C01%7Cted.eckert%40microsoft.com%7C128a6cf65f404a6b202008d4a90a008c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636319307807914554&sdata=w%2BFpIso4C46tDvJYq8r%2B1%2BPqZT6nlziMUNR3yBmiA5k%3D&reserved=0 Instructions: https://na01.safelinks.prot
Re: [PSES] Min size of double insulation symbol relaxed
Did you look at the UL versions of these standards as well as the IEC versions? With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England Sylvae in aeternum manent. -Original Message- From: Scott Xe [mailto:scott...@gmail.com] Sent: 01 June 2017 17:19 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Min size of double insulation symbol relaxed Hi Peter, Thanks for your advice! I read the previous 60056/60950-1/60335-1 standards back to 199x and still could not trace the following requirements. The dimensions of the symbol for Class II construction shall be such that the length of the sides of the outer square is about twice the length of the sides of the inner square. The length of the sides of the outer square shall not be less than 5mm, unless the largest dimension of the appliance does not exceed 15cm, in which case the dimensions of the symbol may be reduced, but the length of the sides of the outer square shall not be less than 3mm. I am unable to recall the originate of this requirement and suspect if it comes from the safety standards. For the time being, I have just to refer to the latest requirements in safety standards without above requirement. Regards, Scott On 1/6/2017, 12:38 AM, "Peter Tarver" wrote: Scott - The CE mark size is mentioned in RED, but not the double insulation symbol. The LVD implicitly defers to the CE Marking Directive for size. IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to refer to the standard used for the product bearing the Symbol 5172 for the answer. Peter Tarver > -Original Message- > From: Scott Xe > Sent: Wednesday, May 31, 2017 08:55 > > Is the minimum size of 5 mm relaxed to the legible reading > in LVD and RED? Where and when does it introduce? The information contained in this message may be privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete or destroy any copy of this 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] Min size of double insulation symbol relaxed
Hello Scott, I believe that there are some product specific standards with the dimensional requirement you mention. IEC 61347-2-13:2009 Annex I section I.4 includes the text you reference. However, this only applies to electronic controlgear for LED modules, not necessarily for other products. This is just the first example I found, and I only found it because a draft SASO adoption is available here<http://saso.gov.sa/ar/eservices/tbt/TBTNoteDoc/A-181.pdf> and it was indexed by various Internet search engines (I’m not sure how IEC copyright licenses are handled in Saudi Arabia.) Ted Eckert Microsoft Corporation The opinions expressed are my own and do not necessarily reflect those of my employer. -Original Message- From: Scott Xe [mailto:scott...@gmail.com] Sent: Thursday, June 1, 2017 9:19 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Min size of double insulation symbol relaxed Hi Peter, Thanks for your advice! I read the previous 60056/60950-1/60335-1 standards back to 199x and still could not trace the following requirements. The dimensions of the symbol for Class II construction shall be such that the length of the sides of the outer square is about twice the length of the sides of the inner square. The length of the sides of the outer square shall not be less than 5mm, unless the largest dimension of the appliance does not exceed 15cm, in which case the dimensions of the symbol may be reduced, but the length of the sides of the outer square shall not be less than 3mm. I am unable to recall the originate of this requirement and suspect if it comes from the safety standards. For the time being, I have just to refer to the latest requirements in safety standards without above requirement. Regards, Scott On 1/6/2017, 12:38 AM, "Peter Tarver" mailto:ptar...@enphaseenergy.com>> wrote: Scott - The CE mark size is mentioned in RED, but not the double insulation symbol. The LVD implicitly defers to the CE Marking Directive for size. IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to refer to the standard used for the product bearing the Symbol 5172 for the answer. Peter Tarver > -Original Message- > From: Scott Xe > Sent: Wednesday, May 31, 2017 08:55 > > Is the minimum size of 5 mm relaxed to the legible reading > in LVD and RED? Where and when does it introduce? The information contained in this message may be privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete or destroy any copy of this 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 mailto:emc-p...@ieee.org>> All emc-pstc postings are archived and searchable on the web at: https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2Femc-pstc.html&data=02%7C01%7Cted.eckert%40microsoft.com%7C128a6cf65f404a6b202008d4a90a008c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636319307807904541&sdata=heJOQDDEYexARH9hPpmAy9soihfiXtzFMkBwdW3zmxM%3D&reserved=0 Attachments are not permitted but the IEEE PSES Online Communities site at https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fproduct-compliance.oc.ieee.org%2F&data=02%7C01%7Cted.eckert%40microsoft.com%7C128a6cf65f404a6b202008d4a90a008c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636319307807914554&sdata=%2FFhm9xBDEDZoQ4BADuWbs%2FyATDcHIjcDwwTP4C3znLo%3D&reserved=0 can be used for graphics (in well-used formats), large files, etc. Website: https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2F&data=02%7C01%7Cted.eckert%40microsoft.com%7C128a6cf65f404a6b202008d4a90a008c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636319307807914554&sdata=w%2BFpIso4C46tDvJYq8r%2B1%2BPqZT6nlziMUNR3yBmiA5k%3D&reserved=0 Instructions: https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2Flist.html&data=02%7C01%7Cted.eckert%40microsoft.com%7C128a6cf65f404a6b202008d4a90a008c%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636319307807914554&sdata=QdZVKCMYL4dN0tQj%2BCQVzRU0AJ568IlSwtn8DB6NlBY%3D&reserved=0 (including how to unsubscribe) List rules: https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2Flistrules.html&data=02%7C01%7Cted.eckert%40microsoft.com%7
Re: [PSES] Min size of double insulation symbol relaxed
Hi Peter, Thanks for your advice! I read the previous 60056/60950-1/60335-1 standards back to 199x and still could not trace the following requirements. The dimensions of the symbol for Class II construction shall be such that the length of the sides of the outer square is about twice the length of the sides of the inner square. The length of the sides of the outer square shall not be less than 5mm, unless the largest dimension of the appliance does not exceed 15cm, in which case the dimensions of the symbol may be reduced, but the length of the sides of the outer square shall not be less than 3mm. I am unable to recall the originate of this requirement and suspect if it comes from the safety standards. For the time being, I have just to refer to the latest requirements in safety standards without above requirement. Regards, Scott On 1/6/2017, 12:38 AM, "Peter Tarver" wrote: Scott - The CE mark size is mentioned in RED, but not the double insulation symbol. The LVD implicitly defers to the CE Marking Directive for size. IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to refer to the standard used for the product bearing the Symbol 5172 for the answer. Peter Tarver > -Original Message- > From: Scott Xe > Sent: Wednesday, May 31, 2017 08:55 > > Is the minimum size of 5 mm relaxed to the legible reading > in LVD and RED? Where and when does it introduce? The information contained in this message may be privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete or destroy any copy of this 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
Re: [PSES] Min size of double insulation symbol relaxed
Scott - The CE mark size is mentioned in RED, but not the double insulation symbol. The LVD implicitly defers to the CE Marking Directive for size. IEC 60417 doesn't have a symbol size for Symbol 5172. You might need to refer to the standard used for the product bearing the Symbol 5172 for the answer. Peter Tarver > -Original Message- > From: Scott Xe > Sent: Wednesday, May 31, 2017 08:55 > > Is the minimum size of 5 mm relaxed to the legible reading > in LVD and RED? Where and when does it introduce? The information contained in this message may be privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete or destroy any copy of this 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
[PSES] Min size of double insulation symbol relaxed
Is the minimum size of 5 mm relaxed to the legible reading in LVD and RED? Where and when does it introduce? Thanks and regards, Scott - 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 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 Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald:
