Issue:
Product Design Features
Product Line:
General Duty Safety Switches
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):
*Endurance test performed at switch rated load current
**Horsepower test - make/break motor inrush/locked rotor current at rated HP
Product Design Features
Product Line:
General Duty Safety Switches
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):
| Endurance Test Number of Operations | HP Test Number of Operations | |||
| Test Standard | At 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 |
**Horsepower test - make/break motor inrush/locked rotor current at rated HP
Released for:Schneider Electric USA
