// CODE SNIPPET
(2) Ungrounded AC Systems
Related Code Sections
(2) Equipment for General Use, Ungrounded AC Systems
A switchboard, switchgear, or panelboard containing an ungrounded ac electrical system as permitted in 250.21 shall be legibly and permanently field ...
National Electrical Code 2020 of Minnesota > 4 Equipment for General Use > 408 Switchboards, Switchgear, and Panelboards > 408.3 Support and Arrangement of Busbars and Conductors > (F) Switchboard, Switchgear, or Panelboard Identification > (2) Ungrounded AC Systems
(B) Wiring and Protection, Ground Detectors
Ground detectors shall be installed in accordance with 250.21(B)(1) and (B)(2). Ungrounded ac systems as permitted in 250.21(A)(1) through (A)(4 ...
National Electrical Code 2020 of Minnesota > 2 Wiring and Protection > 250 Grounding and Bonding > 250.21 Alternating-Current Systems of 50 Volts to 1000 Volts Not Required to Be Grounded > (B) Ground Detectors
240.15 Wiring and Protection, Ungrounded Conductors
single-pole circuit breakers rated 120/240 volts ac, with identified handle ties, shall be permitted as the protection for each ungrounded conductor ...
National Electrical Code 2020 of Minnesota > 2 Wiring and Protection > 240 Overcurrent Protection > 240.15 Ungrounded Conductors
(D) Special Occupancies, Reverse Polarity Device
in accordance with the installation instructions and shall respond to the reversal of the ungrounded and the grounded conductors in the 120-volt ac system ...
National Electrical Code 2020 of Minnesota > 5 Special Occupancies > 551 Recreational Vehicles and Recreational Vehicle Parks > 551.40 120-Volt or 120/240-Volt, Nominal, Systems > (D) Reverse Polarity Device
(3) Wiring and Protection, 3-Phase and 2-Phase Systems
For line-to-line loads in 4-wire, 3-phase systems or 5-wire, 2-phase systems, individual single-pole circuit breakers rated 120/240 volts ac ...
National Electrical Code 2020 of Minnesota > 2 Wiring and Protection > 240 Overcurrent Protection > 240.15 Ungrounded Conductors > (B) Circuit Breaker as Overcurrent Device > (3) 3-Phase and 2-Phase Systems