warning sign shall be provided on or adjacent to each disconnecting means.
Exception No. 1: Where a motor receives electric energy from more than one source, the disconnecting means for the main power supply to the motor shall not be required to be immediately adjacent to the motor, provided the controller disconnecting means is capable of being locked in the open position.
Exception No. 2: A separate disconnecting means shall not be required for a Class 2 remote-control circuit conforming with Article 725, rated not more than 30
volts, and isolated and ungrounded.
X. Adjustable-Speed Drive Systems
430.120 General. The installation provisions of Part I through Part IX are applicable unless modified or supplemented by Part X.
FPN: Electrical resonance can result from the interaction of the nonsinusoidal currents from this type of load with power factor correction capacitors.
430.122 Conductors — Minimum Size and Ampacity. (A) Branch/Feeder Circuit Conductors. Circuit conduc-
tors supplying power conversion equipment included as
part of an adjustable-speed drive system shall have an
ampacity not less than 125 percent of the rated input
to the power conversion equipment.
(B) Bypass Device. For an adjustable speed drive system that utilizes a bypass device, the conductor ampacity shall not be less than required by 430.6. The ampacity of circuit conductors supplying power conversion equipment included as part of an adjustable-speed drive system that utilizes a bypass device shall be the larger of either of the following:
(1) 125 percent of the rated input to the power conversion equipment
(2) 125 percent of the motor full-load current rating as determined by 430.6
430.124 Overload Protection. Overload protection of the motor shall be provided.
(A) Included in Power Conversion Equipment Where the power conversion equipment is marked to indicate that motor overload protection is included, additional overload protection shall not be required.
(B) Bypass Circuits. For adjustable speed drive systems that utilize a bypass device to allow motor operation at rated full-load speed, motor overload protection as de- scribed in Article 430, Part III, shall be provided in the bypass circuit.
(C) Multiple Motor Applications. For multiple motor application, individual motor overload protection shall be provided in accordance with Article 430, Part III.
430.126 Motor Overtemperature Protection.
(A) General. Adjustable speed drive systems shall protect against motor overtemperature conditions where the motor is not rated to operate at the nameplate rated current over the speed range required by the application. This protection shall be provided in addition to the conductor protection required in
430.32. Protection shall be provided by one of the following means.
(1) Motor thermal protector in accordance with 430.32
(2) Adjustable speed drive system with load and speed- sensitive overload protection and thermal memory retention upon shutdown or power loss
Exception to (2): Thermal memory retention upon shutdown or power loss is not required for continuous duty loads.
(3) Overtemperature protection relay utilizing thermal sensors embedded in the motor and meeting the requirements of 430.32(A)(2) or (B)(2)
Thermal sensor embedded in the motor whose communications are received and acted upon by an adjustable speed drive system FPN: The