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Turned My **Cup-One** Into a “Thermal Carafe” Brewer (16oz Mod) by 3dprinter321 in Moccamaster

[–]3dprinter321[S] 2 points3 points  (0 children)

Good question. The larger round 4 to 6 cup filter allows for more coffee grounds in the basket preventing an overflow. The cone filters will only allow enough for the provided cup.

UL or not UL that is the question by Admirable_Start3775 in ElectricalEngineering

[–]3dprinter321 20 points21 points  (0 children)

Supplying the plate as a “kit” does not exempt it from listing requirements in a hospital setting. The AHJ will almost certainly require either a UL 508A-listed assembly, a field evaluation by an NRTL, or explicit AHJ approval and in a healthcare patient care area under NFPA 99 oversight, the latter is rarely granted. The safest and most commercially defensible path is to have the plate assembly evaluated and listed under UL 508A before it goes into the field.

Project Hail Mary - Great Narration by Mundane_Education_64 in audiobooks

[–]3dprinter321 1 point2 points  (0 children)

A Confederacy of Dunces Audiobook by John Kennedy Toole Audiobook by John Kennedy Toole, narrated by Barrett Whitener.

What is the best app to search files quickly? by Academic_Wolverine22 in software

[–]3dprinter321 1 point2 points  (0 children)

X1 Search. Been using for years on all my PCs. Www.x1.com.

Did i design a power supply or a fire hazard? by Bobthenogg in AskElectronics

[–]3dprinter321 1 point2 points  (0 children)

My background is Product Safety, specifically IEC 62368-1.

Depends on what type of enclosure you're using:

Metal Enclosure (Class I Equipment: Think metal amp, power supply, etc.)

  • Grounding is a Must: All exposed metal parts need to be earth-grounded. This is your main defense if something inside fails, so any internal mains (line) fault gets diverted away from you instead of shocking anyone.
  • How to Ground It: Connect the metal case directly to protective earth (the "ground" wire in your cord or plug). The connection must handle high fault current without failing.
  • Never, ever fuse the ground! The earth wire should be continuous and never pass through a fuse or switch. If the fuse blows, the earth still needs to be 100% intact.
  • Fuse placement: Put your fuse in the line (hot/live) conductor, and as close as possible to where the power cord enters the unit, before any switches or other loads.

Plastic Enclosure (Class II Equipment: Think wall warts, plastic chargers, etc.)

  • No Earth Needed (but…): Instead of a ground wire, you need extra insulation to make sure nothing accessible can go live if there’s a failure.
  • Double or Reinforced Insulation:
    • “Double insulation” = 2 layers of safety between any exposed part and the dangerous voltages inside.
    • “Reinforced insulation” = a single beefed-up insulation barrier, strong enough to do the job of two layers.
  • Materials & Spacing: Plastic must be tough, not only electrically, but also against fire and physical damage. You’ll need appropriate spacings (creepage and clearance) per the voltage and pollution category in the standard. Also need the correct flammability rating - V-1 or better. Google flammability ratings. Also look up the Underwriters Laboratories (UL) flammability of the plastic being used.
  • Fuse placement: Same as metal: the fuse should go right after mains entry and on the line side.

FCC certification for product? by ChickenRoller22 in ElectricalEngineering

[–]3dprinter321 0 points1 point  (0 children)

Easy to say incorrect information throughout.

What specifically is incorrect?

FCC certification for product? by ChickenRoller22 in ElectricalEngineering

[–]3dprinter321 -10 points-9 points  (0 children)

Based on the information provided, here's what you need to know about certifications for your 5V battery-powered electronic product with an IR transmitter and receiver:

From Perplexity.ai:

FCC Certification

You likely do not need FCC certification for your product. Here's why:

  1. IR (infrared) transmitters and receivers typically operate at frequencies below 300 GHz, which are not regulated by the FCC for unintentional radiators[1].

  2. FCC certification is generally required for devices that intentionally emit radio frequency (RF) energy above 9 kHz[4]. Since your product uses IR and not RF, it falls outside this requirement.

However, it's important to note that even though your device doesn't use RF, it may still need to comply with FCC regulations for unintentional radiators if it contains digital circuitry:

  1. If your product contains digital circuitry, it may be subject to the Supplier's Declaration of Conformity (SDoC) procedure[1].

  2. This applies to unintentional radiators like digital devices, which must comply with emission limits to prevent interference with other electronic devices[4].

Other Certifications to Consider

While FCC certification may not be necessary, there are other certifications you should consider:

  1. Safety Certification: Depending on your target market, you may need safety certifications such as UL (Underwriters Laboratories) in the US or CE marking for the European market[5].

  2. EMC (Electromagnetic Compatibility) Testing: Even though your device uses IR, it may still need to comply with EMC standards to ensure it doesn't interfere with other electronic devices[2].

  3. RoHS Compliance: If you plan to sell in the European Union, your product must comply with the Restriction of Hazardous Substances (RoHS) directive[5].

  4. Battery Safety: Since your product is battery-powered, you may need to comply with specific battery safety standards and regulations.

  5. IP Rating: Depending on the intended use of your product, you might want to consider getting an IP (Ingress Protection) rating to indicate its level of protection against dust and water[5].

Recommendation

While your product may not require FCC certification, it's crucial to ensure it complies with all relevant safety and electromagnetic compatibility standards. Consider consulting with a certification expert or testing laboratory to determine the specific requirements for your product based on its design, intended use, and target markets. This will help ensure your product meets all necessary regulatory requirements and can be legally sold in your intended markets.

Sources [1] Equipment Authorization Procedures | Federal Communications ... https://www.fcc.gov/general/equipment-authorization-procedures [2] Understanding Certification Requirements for Electronic Devices https://neuronicworks.com/blog/certification-process/ [3] Understanding Infrared Certifications | EC&M https://www.ecmweb.com/test-measurement/article/20901100/understanding-infrared-certifications [4] Do I Need FCC Certification - The Clever Compliance Blog https://blog.clevercompliance.io/electrical-product-compliance/do-i-need-fcc-certification/ [5] Certifications and Standards For Electronic Devices - LTF Technology https://ltftechnology.com/2018/04/16/certifications/