As with any industry, experience working with clients reveals commonalities. At High Tech Design Safety, CEO and founder Steve Barcik Amstel has worked with hundreds of clients on a diverse spectrum of products and industries and still there are things that apply to many and common things that get overlooked with some of the complex products being brought to market. In today’s blog, he lists some of the top misses that he sees when helping companies get their product UL, S2 and CE certified. You can utilize this information to design in your product now.
- Not designed to standards, including at least one electrical standard.
- Lack of correct over current protection for system /subassemblies, breakers and
fuses. - Use of sub assemblies with no conformity information.
Incorrect wire types. - Grounding missing from parts of system, or not specified on drawings as to wire size and type
- All metal parts of the system which can by single fault become energized must be grounded and show less than .1 ohms resistance to ground
- Main ground should be the same size as power conductors
- Lack of guarding
- Lack of required Documentation in Manuals
- Seismic restraints needed
- Safety devices not rated for use in a safety circuit
- Ergonomics, controls or display too high or too low
- Lack of correct over current protection for system and subassemblies.
- Industrial Systems must have 10K AIC minimum interrupting capacity at main breaker
- Must use a main branch protective breaker of type UL 489 for system, UL 489 breakers used for all branch circuits.
- Would be best if breakers also have CE marking
- Use of subassemblies with no conformity information
- Subassemblies must be listed or rated (UL and CE Marked), so that suitability can be determined.
- The details of power and current requirements and withstand are required to design circuit.
- Incorrect wire types.
- Use THHN, TWN, or other wire type.
- Use listed wire that is UL marked
- Use power cable that is UL marked for the use
- Use of AWM wire type should be limited to systems that will be UL listed.
- EMO/Interlock Function is inoperable, incorrect, or missing
- EMOs, interlocks, and safety relay systems must use safety rated parts, Must be UL listed and CE marked
- Must operate fail safe and switch the circuit off to drop power
- Lack of Safety warning Labels, or incorrect formats, IEC or ANSI or SEMI S1
- The labels have three panels and contain the Signal Word, Pictogram, and Message
- The message identifies the hazard, how to avoid the hazard and advises of the potential consequence of not avoiding the hazard.
- Lack of guarding. Hazards must be guarded using appropriate barriers and if required interlocks. Interlocks must stop the hazard. Barriers must be permanent, fixed, and sturdy
- Lack of required Documentation in Manuals – Must provide full details about the system; Intended use, Power and other facilities, Spares, Hazards, and warnings, Details upon details
It is a great idea, even if you think your team is on the right track, to double check and give consideration to each of the applicable common misses listed above. It can save you time and money expediting your path to certification. For a proven and tested path to conformance contact us at High Tech Design Safety, LLC
