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USB的端子,安规异常测试要求

摘要:  想了解一下ICE62368标准,电视机做认证时,有USB的端子的话,安规异常测试的要求: 1、异常状态(过压),输出电压不能超过7V? 2、输出电流不能超过2A? 3、输出短路功率要求小于多少? 就是针对USB输出端子的异常 ...

想了解一下ICE62368标准,电视机做认证时,有USB的端子的话,安规异常测试的要求:
1、异常状态(过压),输出电压不能超过7V?
2、输出电流不能超过2A?
3、输出短路功率要求小于多少?

就是针对USB输出端子的异常测试


5.3 Electrical-caused fire, power sources and safeguards
5.3.1 DC power transfer interconnection to building wiring
To protect the communication cables, including building wiring, and other devices including the PD, the PSE shall implement power limiting control to reduce the likelihood of ignition and shall limit the output current to a value that does not cause damage to the wiring system.

To reduce the likelihood of ignition, the PSE circuit that provides power shall comply with the requirements for a limited power source (LPS) of Clause Q.1 of IEC 62368 1:2014.

NOTE 1 This means that a fire enclosure is not normally required in the power feeding load circuits of the PD.

For interconnection of PSE circuits to other devices for DC power transfer via building wiring, where it is unknown whether remotely attached devices comply with this document, the PSE shall limit the output current to a value that does not cause damage to the wiring system due to overheating, under any conditions of external load up to and including short circuits. The maximum continuous current from the equipment shall not exceed a current limit that is
suitable for the minimum wire gauge specified in the equipment installation instructions.

For a PD that receives multiple power input circuits from one or more PSE, the PD also shall implement power limiting in accordance with PS2 or Annex Q of IEC 62368-1:2014 to control additive power from returning to another PSE under normal operating conditions, abnormal operating conditions and single fault conditions.

NOTE 2 The requirement for single fault condition does not apply to an IC current limiter in compliance with Clause G.9 of IEC 62368-1:2014.

EXAMPLES of such PD equipment are: an analogue telephone, a security camera, a network switch or hub, or devices outside the scope of IEC 62368-1 such as lighting or novelty items.
PSE circuits connected to external paired conductor cable, such as those described in ID numbers 1 and 2 of Table 14 of IEC 62368-1:2014 having a minimum wire diameter of 0,4 mm, shall have the current limited to not more than 1,3 A.

Compliance is checked with 6.2 or Clause Q.1 of IEC 62368-1:2014.

NOTE 3 These safeguards typically apply to equipment that are not located in close proximity to each other, such as those associated with power over Ethernet and similar communication cables.

5.3.2 DC power transfer interconnection to other equipment
For interconnection of DC power transfer PSE circuits to other equipment, via either direct plug-in connectors or via fly leads, where it is unknown that the attached devices are likely to comply with IEC 62368-1, the delivered power shall comply with either PS2 or Clause Q.1 of IEC 62368-1:2014.

EXAMPLES for such equipment are a scanner, mouse, keyboard, DVD drive, CD-ROM drive, camera, network switch or hub, or devices outside the scope of IEC 62368-1, such as lighting or novelty items.

Compliance is checked in accordance with 6.2 or Clause Q.1 of IEC 62368-1:2014.

For PSE circuits under abnormal operating conditions and single fault conditions in the PSE, the available output power shall not exceed the specified fault current rating in the power delivery specification. Where there is no prescribed maximum fault current specified for the standardized interface, the available current shall not exceed the rated maximum output current of the power delivery specification by more than:
– 50 % for circuits equal to or less than 2 A for more than 5 s; and
– 30 % for circuits greater than 2 A for more than 5 s; and
– shall not exceed 8,0 A under any circumstances.

For example, for USB PSE circuits under abnormal operating conditions and single fault conditions in the PSE, a rated current of 3 A is specified in the USB power delivery specification for USB Micro-A, Micro-AB and Micro-B connectors and a rated current of 1,8 A in the USB 2.0 and USB 3.0 specification.

NOTE 1 Other USB specifications use higher values, such as 5 A or 6 A.

Compliance is checked by inspection and test.
NOTE 2 These safeguards typically apply to equipment and accessories located in close proximity to each other, such as those associated with USB and similar communication cables.

5.4 Safeguards to protect against a single fault condition in the PSE
NOTE See Annex B for the rationale for 5.4.1 and 5.4.2.

5.4.1 Requirement for the PSE
Under single fault conditions in the PSE with a single output, the output voltage of the PSE shall not exceed 130 % of the nominal rated output voltage and shall not exceed ES2 limits at the relevant DC power transfer port of the PSE.
For PSEs that can deliver a range of different nominal output voltages via negotiation with the PD (for example USB power delivery), if it is not always known what type of PD will be attached, the voltage from the PSE under single fault conditions shall be limited to
– 130 % for circuits greater than 5 V (with a minimum of 7,5 V), and
– 150 % for circuits equal to or less than 5 V of the nominal output voltage that was negotiated.
5 V/9 V (> 15 W and up to 27 W rating), 5 V/9 V/15 V (> 27 W and up to 45 W rating) and 5 V/9 V/15 V/20 V (> 45 W and up to 100 W rating), with current not to exceed 3 A (up to 60 W rating) or 5 A (> 60 W at 20 V). Other
voltages are allowed in the specification provided that the required voltages and currents are supported for the PSE rating. These rules supersede the previous "Profiles", and are normative (the previous profiles were optional
normative).

5.4.2 Requirement for the PD
The PD shall not create any hazard when supplied with
– 130 % of the nominal rated input voltage of the PD at the relevant DC power transfer port for circuits greater than 5 V (with a minimum of 7,5 V); and
– 150 % of the nominal rated input voltage of the PD at the relevant DC power transfer port for circuits equal to or less than 5 V.

Any consequential failure of components in the PD shall not create a hazard.

标准下载 IEC 62368-3_2017 Ed.1.0
IEC 62368-3_2017 Ed.1.0.pdf

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评论(1)

  1. 所以说,电流没有超过2A的说法,标准不限定你多少电流与电压,但是需要有协议,通信协议保证安全,好像现在有几百瓦的PD快充都出来了。肯定大于7V、2A的电流了。

    想了解一下ICE62368标准,电视机做认证时,有USB的端子的话,安规异常测试的要求:
    1、异常状态(过压),输出电压不能超过7V?
    2、输出电流不能超过2A?
    3、输出短路功率要求小于多少?

    就是针对USB输出端子的异常测试