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What is the rating of the number of switching operations of Square D, 30 - 60A, General Duty, F-Series Safety Switches? These ratings are also sometimes referred to as Endurance operations and Horsepower-overload operations.

Issue:
Product Design Features

Product Line:
General Duty Safety Switches

Environment: 
Mechanical Endurance

Cause:
Application

Resolution:
For Safety Switches, the standard for design and testing of the number of switching operations is governed by UL98 and NEMA KS-1.There are two separate tests: (1) Endurance Test, and (2) Horsepower-overload test. The below table shows the minimum number of operations required (OFF to ON to OFF) by UL and NEMA. For the endurance test, however, Square D F-Series Safety Switches exceed the UL and NEMA requirements by up to 3 times the total (see below table).

NUMBER OF OPERATIONS
Square D Safety Switches (F-series)
30 - 60A, General Duty
-------------------------Endurance test # of ops------------------. . . . . . . ----HP test # of ops
test stds.....rated Load*...... No-Load...... total (L + NL) . . . . . . . . . . . . . at rated HP**
UL...................6000..................4000.................10000 . . . . . . . . . . . . . . . . . . . . 50
NEMA............6000..................4000.................10000 . . . . . . . . . . . . . . . . . . . . 50
Square D.........6000................24000.................30000 . . . . . . . . . . . . . . . . . . . . 50
* endurance test done at switch rated Load current
** horsepower test - make/break motor inrush/locked rotor current at rated HP


Number of switching operations for other General Duty safety switches:
For 30-60A series E General Duty safety switches, see FA112144
For 100A series F General Duty safety switches, see FA99734
For 200A series F General Duty safety switches, see FA99735
For 400A series E General Duty safety switches, see FA99736
For 600A series E General Duty safety switches, see FA99737
For 800A series E General Duty safety switches, see FA99761

CTA-ID : 2003375
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