The previous 2001 version of the security company specification UL60950-1 for power provides expires in December 2010. Often revision modifications are minor for industrial power provides, however one key part is affected this time. The 2005 version stipulates that any surge suppressor on the primary facet shall be a VDR (Voltage Dependant Resistor) which have to be adjust to Annex Q and be accepted to IEC 61051-2.
To conform, power supply producers should modify their designs and retest to display compliance to the immunity specification EN61000-4. That is going to be pricey in both Engineering labor prices (alternative value) or external take a look at home charges.
Producers could now determine to out of date gradual shifting merchandise earlier than December 2010 and proceed investing in new merchandise.