Chassis Specifications; RoHS
Restriction of Hazardous Substances
The RoHS standard limits the amount of certain elements used in the manufacture of electronic components. There are six chemicals that are controlled under the standard. These metals include: lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls and polybrominated diphenyl ethers.
The materials are not banned, but limited in concentration. A maximum concentration value of less than 0.1 percent by weight in homogenous materials of lead, mercury, hexavalent chromium, polybrominated biphenyls or polybrominated diphenyl ethers. And a maximum concentration value of less than 0.01 percent by weight in homogenous materials of cadmium.
Lead (Pb); used in Lead Terminal Finishes, Solder. May be replaced by Tin.
Mercury (Hg); is not normally used.
Cadmium (Cd); used in Terminal Finishes. May be replaced by Tin Hexavalent.
Hexavalent chromium (Cr VI); used as a Protective Coatings. May be replaced Trivalent Chromium
Polybrominated biphenyls (PBB); used as a Flame Retardant in plastics.
Polybrominated diphenyl ethers (PBDE); used as a Flame Retardant in plastics
Exemptions to RoHS
Items outside the scope of the RoHS Directive include:
Specialized military systems
Avionics systems
Equipment for national security
Equipment built for own use (hobbyist)
Spares for products placed onto the market before July 1st, 2006
Equipment for capacity expansion or upgrades on product placed onto the market before July 1st, 2006
Keep in mind that parts may be available now but unless spares are procured parts may not be available when needed years later. If you need and purchase a non RoHS part be sure to make a Life Time purchase to insure that parts will be available when needed.
RoHS devices are clearly defined within the data sheet. In many cases common components are receiving new part numbers to designate RoHS compliance. For example a standard part purchased for years may no longer be available after being replaced by its RoHS counter-part. Many components that contained lead [for example] are now obsolete in favor of the physically identical part that does not use lead [Pb]. However the new Lead-free part has a new part number.
Chassis Thermal Design; Next topic in designing a chassis
ELV Compliant
End of Life Vehicles (ELV) Directive 2000/53/EC requires that certain automotive products be free (except for trace impurities) of mercury, cadmium and lead as of 2003-7-1. Lead can still be used as an alloying additive in copper, steel and aluminum and in solderable applications. These products comply with the ELV directive. [Similar to the RoHS requirement, which might be found on some data sheets. Also see below]
EU RoHS/Not ELV Compliant
These products comply with the Restrictions on Certain Hazardous Substances (EU RoHS) Directive 2002/95/EC but NOT the End of Life Vehicles (ELV) Directive 2000/53/EC. These products utilize exemptions in the EU RoHS Directive that are not allowed in the ELV Directive. Typical examples are lead in compliant pin connector systems (pressfit connectors) and cadmium in electrical contacts.
How To Specify a Equipment Chassis; Index page
