The old 2001 version of the safety agency specification UL60950-1 for power supplies expires in December 2010. Usually revision changes are minor for industrial power supplies, but one key component is affected this time. The 2005 version stipulates that any surge suppressor on the primary side shall be a VDR (Voltage Dependant Resistor) which must be comply with Annex Q and be approved to IEC 61051-2.
To comply, power supply manufacturers will have to modify their designs and retest to demonstrate compliance to the immunity specification EN61000-4. This is going to be costly in either Engineering labor costs (opportunity cost) or external test house fees.
Manufacturers may now decide to obsolete slow moving products before December 2010 and continue investing in new products.
Friday, October 9, 2009
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