IEC61000-3-3 requirement for the device designed for the US market - Page 1
Forum section: electronics / projects

author: semir-t
author_rank: Regular Contributor
timestamp: March 03, 2022, 09:12:14 am
content: Hello.I need help and I was hoping someone on this forum could help me out. We are designing device for the US market and we need to create the list of the required EMC standards that we need to comply with.The problem is that I can't find if we need to comply with the IEC61000-3-3 (Voltage flickering). It says in the standard, that only devices below 16A (we have 10A nominal value) and with supply voltage rated between 220V-250V should comply with this standard. But because our device should only be connected to the 110V power supply I am unsure if we need to list this standard.Hope someone will be able to help me. Thanks in advance.

author: jonpaul
author_rank: Super Contributor
timestamp: March 03, 2022, 09:20:55 am
content: The IEC flicker std applied to devices like heaters that have an ON/OFF control to achieve an average power but pulse the load. EG SCR/TRIAC or thermal relays on stoves, heaters, etc.Also very intermittent loads like copy machines. What is the device you're designing?In USA each utility customer is "connected to a 220..240V distribution system" via the utility transformer, which provides a 240 and 120 mains to the building.From the IEC IEC 61000-3-3, descr:IEC 61000-3-3 is the standard that deals with the limitation of voltage fluctuations and flicker impressed on the public low-voltage system. It specifies limits of voltage changes which may be produced by an equipment tested under specified conditions and gives guidance on methods of assessment.It is applicable to electrical and electronic equipment having an input current equal to or less than 16 A per phase, intended to be connected to public low-voltage distribution systems of between 220 V and 250 V line to neutral at 50 Hz, and not subject to conditional connection. IEC 61000-3-3 has the status of a product family standard within the IEC 61000 series, and is part of a regulatory compliance program needed to show compliance to the EU EMC Directive, 2014/30/EU.IEC 61000-3-3 identifies the applications of limits and specific test conditions for specific equipment types.General Equipment RequirementsHotplatesBaking OvensGrillsBaking Ovens/Grills Combination UnitsMicrowave OvensLighting and similar equipmentWashing MachinesTumbler DryersRefrigeratorsCopy Machines, Laser Printers, and similar DevicesVacuum cleanersFood MixersPortable ToolsHairdryersTelevision Sets, Audio Equipment, Computers, DVD Players, and Similar EquipmentDirect Water HeatersAudio Frequency AmplifiersAir Conditioners Dehumidifiers, Heat Pumps, and Commercial Refrigeration EquipmentArc Welding EquipmentBon chanceJon

author: semir-t
author_rank: Regular Contributor
timestamp: March 03, 2022, 09:22:14 am
content: This device has an heater element which will be used to heat the water. We will be using PID regulator to achieve desired temperature of the heating element.

author: jonpaul
author_rank: Super Contributor
timestamp: March 03, 2022, 09:41:10 am
content: Rebonjour, a PID contrôle does not specifically adresse the power control. It is any second,order control system.Is the methods of power modulation for instance with SCR, Triac, so mains fréquence phase control?Or aperiodic On off modulation like a primitive mechanical thermostat or soldering iron ?Jon

author: semir-t
author_rank: Regular Contributor
timestamp: March 03, 2022, 09:51:07 am
content: We have Triac on our design. We are using the Zero-Cross Triac driver (MOC3063) to control the triac, and our control is ON-OFF.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 03, 2022, 12:49:21 pm
content: Quote from: semir-t on March 03, 2022, 09:12:14 amThere's your answer - it's not applicable.

author: semir-t
author_rank: Regular Contributor
timestamp: March 03, 2022, 01:23:57 pm
content: Thanks. Yes that is what we thought but for some reason we weren't that sure and we needed the confirmation.We understand the reason behind this requirement in a term that our device shouldn't affect the power network voltage, and I saw some older device do just this where by turning them one light bulb would start to flicker. The confusion was related to the part that we assume that same thing would happen on the 110V power network so we weren't sure why this requirement wouldn't be applicable.But, nonetheless if it is not applicable its a good for us, less thing to worry about.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 03, 2022, 01:56:21 pm
content: Quote from: semir-t on March 03, 2022, 01:23:57 pmIt always will due to there being a nonzero source impedance, but at least in the US, electrical codes specify how much the voltage is allowed to drop at the rated current of the circuit. For particularly long runs, the wiring has to be upsized to meet that requirement. That applies at the outlet, so for a device that plugs into the outlet, you just have to make sure it does not pull more current than the rating of the outlet and that it will tolerate the maximum allowed voltage drop. You can test that very cheaply by adding extension cords to add series resistance.

author: jonpaul
author_rank: Super Contributor
timestamp: March 03, 2022, 02:14:06 pm
content: Hello again I believe that ,the IEC applies. I would not base a safety or regulatory decision on a,few,forum posts. Perhaps you haven't interpreted the 120/240 exact meaning of the standard.Strongly Suggest to contact approval labs in USA, with more precise products information,Underwriters Laboratoires UL, or Electric Testing Laboratoires ETL.Finally the Mike Holt forum has many professionals.Bon chanceJonJon

author: semir-t
author_rank: Regular Contributor
timestamp: March 03, 2022, 02:24:56 pm
content: Thank you for your answers. We will try to contact approval labs in the USA through our client. They might help us clear the confusion. We have one laboratory that we want to use for pre-compliance testing I assume they will be able to provide us this information.

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 03, 2022, 02:45:02 pm
content: As long as you don't try to pull more current than the circuit is rated for, a compliant circuit will never drop more voltage than what the standard allows.

author: tooki
author_rank: Super Contributor
timestamp: March 05, 2022, 01:53:49 pm
content: Quote from: semir-t on March 03, 2022, 09:12:14 amThen you should probably design to the correct voltage, which is 120V±5%, and has been since 1954.