UL Approval

[CW]

I used to make adapters and mounting cabinets for high voltage breakers, in addition to modification to the breaker themselves. They were always sent, assembled with breaker, to be UL tested. They only required one to be sent. They do not destroy them. The only reason they would be destroyed during testing is if it would not do what it was meant to do. UL rating only certifies that the device will perform as the manufacturer says it will. It is only a certification that you are not making a false claim, not that it will be safe. I have no idea how much it costs though. I just made them.

[CW]

We did all the time. Yes, it was a large organization. There were three of us.

[Chipper Wood]

One might find more information here :

Seems at a quick glance that unless there is a new process or material involved, their testing is to compare a manufactured item to standards already established for similar items along with the materials and other listed manufactured items used in its construction. Researching it for safe combinations and stability for its intended use. A rejection would mean choosing other material/s or modified design or a simple warning label and resubmitting. Also they reserve the right to do periodic paid for visits to the manufacture to insure consistency to the original item listed. I feel that this is more for items that require complicated production control like special tolerances, x-rays etc. or special bonding procedures and the like. Your item might only require an occasional sample of current production. Perhaps the cost might not be as prohibitive as expressed here. You can phone, write or email inquiries to them. At least that part seems to be free.

The originator of this product is looking to reduce his liability insurance premiums. Have you noticed the cost of ladders. Additionally the warning and approval labels on them ? D--n Lawyers !

I would be interested as to what you find and decide.

[Steve Dunbar]

Try asking in sci.engr.electrical.compliance.

[Kevin Daly]

First, UL doesn't approve anything. An item can be either UL recognized or UL listed. Typically, UL listings are for complete assemblies (a lamp for example) while UL recognitions are for components that go into a listed item (the wires in the lamp). I never needed any special records for our UL Listed inverter systems, the UL safety auditor would once in a while come in and check to see that we had everything in the cabinet that we said we did. Depending on the product and its application, the costs vary widely from a few hundred dollars to thousands. If you use only UL recognized components in your assembly, the listing process is much less expensive. If you're custom building the item without UL recognized components, the process is much more expensive and involved as every component will require safety testing at UL's labs. I suggest you contact UL directly and talk to them first. (I've only dealt with UL for the past 15 years or so). E-mail me offline and I can give you some phone numbers and names to contact.

Kevin Daly Mattatuck Astronomical Society

[Robin Lee]

Tom -

Contact your local Hydro authority - they may have the ability to inspect (and approve) small run custom devices. They then put an approval sticker on whatever it is... cost could be $5-10 per sticker...

Sort of like having the electrical inspector approve your home wiring...

Cheers -

Rob

[Edwin Pawlowski]

Correct. Depends on the standard. Just so happens everything I ever sent to them had to comply with a flame spread standard and the only way to test them was to burn them. Once that test was done, to maintain compliance you had to certify that you used the appropriate material and be able to trace back from finished product to the lot number of the material from our supplier. This may or may not apply on the cases in question. Inspection was every quarter. It could take five minutes, could take five hours. Ed

[Lazarus Long]

I speak from my perspective. I don't work for UL.

UL listing essentially means that the item listed is safe for it's intended use. UL, as others have noted, doesn't approve anything. In my employers case, all the stuff we have is put on our listing. It's UL listed. I must further note that the amount of testing our products endure is considerably less that starting from scratch since most of the componentry is UL recognized. Switches, wires, the plastics inside, transformers and so on. The manufacturer of each item has already done their part of the UL testing process. I shudder to think of the rigorous testing one my designs would endure were I to need to test each and every component exhaustively. The listing process is made considerably easier by the plastic having a yellow card. By the switch itself being recognized. And so on.

What my design has to do is be safe (won't cause harm) to the user. UL is not concerned if my device actually does the function I intend it to do. Just be safe. That's it.

Again, I urge the OP to contact UL directly to determine what would actually have to happen if he really want's to get his project listed. IMHO it may not be worth the effort for a few hundred units. But what do I know? I'm not in the OPs business.

[Lazarus Long]

I say recognized in the sense of average Joe looking at the label.

[Lazarus Long]

I don't think I'd want to defend myself in court if I'd used such a deception if a product failed resulting in personal injury or property damage.

[Dave W]

Buy a power cord with a UL sticker on it, connect to unit.....job done and customer happy. DAVe