Pantograph switch is popular in Europe another IEC marketplaces but no much use in the USA. Careful analysis should is suggested prior to specifying a pantograph switch in the ANSI marketplace. Traditionally disconnect switches are governed by four key organizations—NEMA, ANSI, IEEE, and IEC. Today each governs some specific aspects of disconnect switch design.
QUOTE:
[li]NEMA rated disconnect switches are the most robustly designed but are pricey[/li]
[li]If the disconnect switch can meet the ANSI/IEEE requirements it can always meet the IEC requirements but cannot meet the NEMA requirements.[/li]
[li]Disconnect switches designed to IEC requirements are best suited to countries which have light load currents, which have small fault currents, and which do not wish to have or do not require the same margin of safety desired and required in the U.S. and Canadian electric power grids.[/li]
NOTE: NEMA standards allow only a 30 degrees C temperature rise; ANSI/IEEE standards allow a 53 degrees C temperature rise and IEC standards allow a 65 degrees C temperature rise. NEMA standards require a 4-second short circuit withstand; ANSI/IEEE standards require a 3-second short circuit withstands, and IEC standards require only a 1-second short circuit withstand.
