When is UL listing required?

Electronics
#21

There are several EMI Test Laboratories in the North Texas area.
1). The DMS Electronics Lab does NOT have this type of equipment. EMI Test facilities cost about $2M, just beyond their budget a bit.
2). Northwest EMC in Plano (just renamed Element Dallas-Plano), is located on Plano Parkway about 2 miles east of Fry’s Electronics. I have never used them.
3). Veritas National Lab in Lewisville, located just north of the old downtown area. I used them many, many years ago when they were under a different name.
4). Environmental Test Labs (ETL) in Dallas used to test EMI about 20 years ago, not anymore.
5). Professional Testing (PTI) is located in Round Rock, TX. I’ve used their facilities as well but quite a drive to get there. But they may be cheaper.
6). National Technical Service (NTS) is located on Plano Parkway about 1/4 mile east of Fry’s Electronics. They are a one stop shop for this type of testing. Your sales contact at NTS is Scott Oates. I would prefer you try this place first, besides… Scott Oates knows me as a regular customer. In fact, I’ll be doing some EMI testing of huge power supplies there maybe next week. scott dot oates at nts dot com

Save your $$$ for this type of testing as it is not cheap. After all, they have to pay for a mega Million dollar facility.

1 Like
#22

I read the thread and this is for a reading who’s interested. I figure you already did the work.

You need a UL FM or CSAus if you’re reselling it. If you’re building for your own use, you need a professional engineer in your organization to sign off on the drawings.

You mentioned that you are involved with hazardous materials. If there’s an electrical circuit going from your control to the hazardous area (refueling area are designated as such) than you definitely need to limit the energy of that circuit. An arc resulting from an electrical fault could blow up the place if the temperature of the arc is greater than the flashpoint of that hazardous material. There are ways and commercial barriers to limit that energy. Again, you’ll need an engineer to sign off on the drawings.

In the old days, people used explosion proof enclosures. That is cost restrictive today. Also positive air pressure in the enclosure to hazardous materials that are not expected to be present but might is another way.

The standards in your area may require you to use CSA/FM/UL approved equipment in the non hazardous area, to work with Class 1/2 Div 1/2 equipment. Regions can apply extra requirements over and above the NEC standards. That’s why a professional engineer is required.

Since you’re asking these questions, you’re not the man to sign off on the drawings. Get a hold of an engineer.

The engineer with have professional insurance. If it blows up and they find it was related to improper design, then the engineer who signed it will be liable. His insurance will protect him. His professional status allows him to purchase insurance.

#23

We are trying to make a device that will be available on US market. It is powered by 2 rechargeable LIR2450 batteries (max voltage: 4.2 Volts) and we are using ESP32 WI-FI module. I am not sure that if our device needs UL or not. We already got FCC certification.

I would be very happy if anyone can help me.
Thank you!

#24

I do not believe that your low-power devices need UL certification but there are some voluntary standards regarding rechargeable batteries that you may or may not care about.

#25

Is UL Certification Required for Your Hardware Product?

Is UL approval required on all items sold in the USA

This is a good summary as it also covers FCC (WI-FI) and UL (Underwriters Laboratories) UL certification is necessary in the United States and Canada if the product plugs directly into an AC outlet. Primarily the UL is concerned with the electrical safety of your product. Also talks about Blu Booth Licensing,

If you buy already certified chargers you may be OK. Oh minimum of $8 license fee for Blue Tooth if you use that term.