Manual Transfer Switch UL Specifications

A manual transfer switch must be listed under the UL 1008 standard. Under this specification, a contractor must furnish, deliver, install, and test a manual transfer switch. Specific to transfer switches, UL 1008 is designed to provide rigorous requirements for testing the functionality of your manual transfer switch.

Keep reading to learn more about the UL specifications for manual transfer switches.

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Manual Transfer Switch UL 1008 Specifications

The UL 1008 specification is mandatory for all manual transfer switches operating above 750V AC (alternating current). Under UL 1008, an electrical manufacturer must:

  • Provide a complete factory assembled, wired, and tested manual transfer switch.
  • Hi-pot test the manual transfer switch for a period of at least 60 seconds.
  • Meet all NEC regulations when installing a manual transfer switch.
  • Install the manual transfer switch as shown on the drawings and in accordance with the manufacturer’s written instructions.

Additionally, under UL 1008 for manual transfer switches, manual transfer switches:

  • Should consist of two mechanically-interlocked molded case circuit breakers, cam-style male connectors, power distribution block, and grounding terminals hosted within a padlockable enclosure.
  • Should have a main access through an interlocked, hinged door extending the full height of the enclosure.
  • Should have a hinged flap door to cover all cable openings when cables are not connected.
  • Should have a hinged flap door allowing cable entry only after the main access door is open.
  • Should have male cam-lok that are color coded and UL listed single-pole separable types, rated 400 amps at 600V AC.
  • Should have male cam-lok connectors only accessible if both molded case circuit breakers are off and the main access door is open.
  • Should have a power distribution block for load-side field wiring that is factory wired to the molded case circuit breakers.
  • Should have two circuit breakers—one wired from the utility power and the other from the portable generator.

A manual transfer switch under UL 1008 specification can transfer power at least 3,000 times with at least 1,000 changes under at least 100 percent of the rated load, while UL 1008 manual transfer switches rated at lower amperes must be able to complete at least 6,000 transfers under 100 percent load or greater.

UL 1008 Listed Manual Transfer Switches from PSI Control Solutions

If you’re ready to purchase a manual transfer switch for your property, contact PSI Solutions to speak with one of our engineers. We’ll custom-build a UL 1008 listed manual transfer switch that meets your application needs.

contact PSI today!

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