IEC 60079-7:2015/ISH1:2016

Intrepretation sheet 1 - Explosive atmospheres - Part 7: Equipment protection by increased safety "e"

Feuille d'intreprétation 1 - Atmosphères explosives - Partie 7: Protection du matériel par sécurité augmentée "e"

General Information

• Status: Published
• Publication Date: 14-Sep-2016
• ICS: 29.260.20 - Electrical apparatus for explosive atmospheres
• Technical Committee: TC 31 - Equipment for explosive atmospheres
• Current Stage: PPUB - Publication issued
• Start Date: 30-Sep-2016
• Completion Date: 15-Sep-2016

Relations

• Revises: IEC 60079-7:2015 - Explosive atmospheres - Part 7: Equipment protection by increased safety "e"
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL ELECTROTECHNICAL COMMISSION
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IEC 60079-7
Edition 5.0  2015-06
EXPLOSIVE ATMOSPHERES –
Part 7: Equipment protection by increased safety 'e'

INTERPRETATION SHEET 1
This interpretation sheet has been prepared by IEC technical committee 31: Equipment for
explosive atmospheres.
The text of this interpretation sheet is based on the following documents:
ISH Report on voting
31/1258/ISH 31/1272/RVD
Full information on the voting for the approval of this interpretation sheet can be found in the
report on voting indicated in the above table.
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IEC 60079-7:2015 Edition 5.0, Explosive atmospheres – Part 7: Equipment protection by
increased safety “e”
Question:
Do the requirements given in 5.2.3 prohibit the use of a terminal box opened to the interior of
a motor rated 1 kV or greater, provided the interior of the machine has an ingress protection
of IP54 or greater?
IEC 60079-7:2015 Edition 5.0
5.2.3 Degrees of protection provided by electrical machines, Level of Protection “ec”
The requirements of 4.10 apply, except that terminal boxes attached to electrical machines
operating at voltages up to 1 kV, may be opened to the interior of the machine, only when the
degree of protection of the electrical machine is at least IP44. Covers and entries of the
terminal box shall provide at least degree of protection IP54.
ICS 29.260.20
IEC 60079-7:2015-06/ISH1:2016-09(en-fr)

– 2 – IEC 60079-7:2015/ISH1:2016  IEC 2016
Answer:
No. As long as the interior of the machine has an ingress protection of IP54 or greater,
determined in accordance with IEC 60079-0, there is no limitation to less than 1 kV. If the
interior of the machine has an ingress rating of IP44 or lower, the use of a terminal box open
to the interior of a motor rated 1 kV or greater is not permitted.
NOTE Many manufacturers opt to declare IP44 for the machine for certification purposes, whilst claiming a rating
of IP54 or higher, by assessment, for contractual purposes in order to avoid the difficult testing required for
certification of the IP of larger machines. As such, this additional IP rating need only comply with IEC 60529 or
IEC 60034-5 as applicable, and not with any of the testing detailed in IEC 60079-0.

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
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IEC 60
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