2023年IEC 60079-11 Edition7.0：Explosive atmospheres-Part 11: Equipment protection by intrinsic safety “i”发布，关于信号隔离器部分，澄清了IEC 60079-28：Explosive atmospheres-Part 28: Protection of equipment and transmission systems using opticalradiation不适用于独立式光隔离器，增加非光学信号隔离器选项。 以下内容为IEC 60079-11 Edition 7.0标准。
7.10.1 Overview
The requirements of 7.10 apply to signal isolators other than transformers (see 7.8), relays (see 7.9) or individual capacitors (see 7.5) that use optical, magnetic, capacitively coupled and galvanically isolated components.
For "IA" and "IB" level protection, if 7.10.2 and 7.10.3 or 7.10.4 are not complied with, the signal isolator's short-circuit fault on galvanic isolation and any resistance value shall be considered a non-counting fault;
For "IC" level protection, signal isolators that do not comply with 7.10.2 and 7.10.3 or 7.10.4 shall be considered failures as specified in 7.2, including faults in jumper electrical isolation;
The requirements of IEC 60079-28 do not need to be applied to stand-alone opto-isolators that comply with this document.
7.10.2 Signal isolators on which intrinsic safety depends
Signal isolators that have been assessed in accordance with the requirements of 7.1 and meet the following conditions shall be deemed to be likely to fail in accordance with Table 18.
In cases where an external protection element is required to meet the signal isolator rating, the count fault should not be applied to the protection element, which should have a rated safety factor of 1.0. For example, a parallel Zener diode is protected by a fuse of an appropriate rating in accordance with 7.11 with a safety factor of 1.0 to be considered adequately protected, and such components should be isolated in accordance with general industry standards (see Figure 3).
The external connection of the isolated portion of a jumper signal isolator shall comply with the provisions of 6.5.1, but the isolation requirements shall not apply to the interior of a packaged or sealed signal isolator unless required in 7.10.3.
The galvanic isolation of the signal isolator must meet the dielectric strength requirements specified in 6.9. The manufacturer's insulation voltage rating for trouble-free isolated components shall not be lower than the test voltage required by 6.9;
Non-optical signal isolators and optical isolators intended for power transmission should comply with the differential leakage current transmission limit of 50 μA measured at 9.9 or obtained from the signal isolator manufacturer under the most demanding data rate conditions for the application under consideration. The current transmission of the signal isolator is not necessary to consider when evaluating the device;
Note: Optical signal isolators are excluded from the transmission current evaluation on the assumption that the optical transmission energy of a known structure does not violate the current transmission limit.
如果信号隔离器符合7.10.2的要求，对于"ia"和"ib"等级，跨接电隔离的短路仍需要考虑计数故障。 但符合7.10.3或7.10.4的信号隔离器不应视为隔离器短路故障。 以下内容为IEC 60079-11 Edition 7.0（Explosive atmospheres-Part 11: Equipment protection by intrinsic safety “i”）标准。
7.10.3 Signal isolators between intrinsically safe and non-intrinsically safe circuits
A signal isolator that meets one or more of the following requirements may be considered to provide reliable isolation between intrinsically safe and non-intrinsically safe circuits:
a) Optical signal isolators that meet the requirements of IEC 60747-5-5 (International Safety Standard for Optocouplers) reinforced insulation structure, materials and tests, with an insulation rating of at least 6.5.5 for the required voltage. Signal isolators should also comply with the provisions of 7.10.2.
b) Non-optical signal isolators that meet the construction, material and test requirements of the DIN VDE V 0884-11 or IEC 60747-17 (Semiconductor devices – Part 17: Magnetic and capacitive couplers for basic and reinforced insulation) standards, with an insulation class of at least the voltages required in 6.5.5 of this document. Signal isolators should also comply with the provisions of 7.10.2.
c) The signal isolator shall comply with 7.10.2 and comply with the isolation requirements in 6.5.4.2 applicable to the inside of the equipment, but inside the sealed equipment, columns 5, 6 and 7 of Table 7, or columns 3 and 4 of Table 8 and Table 9 shall not apply.
d) The optical signal isolator meets the requirements of 6.9 in terms of galvanic isolation and 9.10 in terms of protection classes "IA" and "IB". The rating of an optical signal isolator does not have to conform to 7.1 or 7.10.2, but the isolation requirements of 6.5.4.2 must apply to both the external connection across isolation and the internal of the optical signal isolator. Inside the sealing equipment, columns 5, 6 and 7 of Table 7, or columns 3, 4 and 5 of Table 8, and columns 3 and 4 of Table 9 shall not apply.
Note: This document does not require verification of the specifications of the signal isolator manufacturer according to IEC 60747-5-5, DIN VDE V 0884-11 or IEC 60747-17.
7.10.4 Signal isolators between independent intrinsically safe circuits
If 7.10.2 or 7.10.3d) is complied with, the signal isolator shall be considered to reliably isolate the independent intrinsically safe circuit. To avoid exceeding the rating of the isolated part, protection techniques (as described in 7.10.2) may be required.