Collapse to view only § 111.70-3 - Motor controllers and motor-control centers.
- § 111.70-1 - General.
- § 111.70-3 - Motor controllers and motor-control centers.
- § 111.70-5 - Heater circuits.
- § 111.70-7 - Remote control, interlock, and indicator circuits.
§ 111.70-1 - General.
(a) Each motor circuit, controller, and protection must meet the requirements of sections 4-8-2/9.17, 4-8-4/9.5 and 4-8-3/5 of ABS Marine Vessel Rules; sections 6-1-7/9.9 and 6-1-7/9.15 of the ABS MOU Rules; or IEC 60092-301:1980 (all three standards incorporated by reference; see 46 CFR 110.10-1), as appropriate, except for the following circuits:
(1) Each steering gear motor circuit and protection must meet part 58, subpart 58.25, of this chapter.
(2) Each propulsion motor circuit and protection must meet subpart 111.35 of this part.
(b) In ungrounded three-phase alternating current systems, only two motor-running protective devices (overload coil or heater type relay within the motor and controller) need be used in any two ungrounded conductors, except when a wye-delta or a delta-wye transformer is used.
(c) The motor disconnecting means must be an externally operable switch or circuit breaker.
§ 111.70-3 - Motor controllers and motor-control centers.
(a) General. The enclosure for each motor controller or motor-control center must meet either NEMA ICS 2 and NEMA ICS 2.3, or Table 1 of IEC 60092-201:2019 (all incorporated by reference; see § 110.10-1 of this subchapter), as appropriate, for the location where it is installed. In addition, each such enclosure in a hazardous location must meet the requirements of subpart 111.105 of this part. NEMA ICS 2.4 (incorporated by reference; see § 110.10-1 of this subchapter) provides guidance on the differences between devices meeting NEMA and those meeting IEC for motor service.
(b) Low-voltage release. Each motor controller for a fire pump, elevator, steering gear, or auxiliary that is vital to the vessel's propulsion system, except a motor controller for a vital propulsion auxiliary which can be restarted from a central control station, must have low-voltage release if automatic restart after a voltage failure or its resumption to operation is not hazardous. If automatic restart is hazardous, the motor controller must have low-voltage protection. Motor controllers for other motors must not have low-voltage release unless the starting current and the short-time sustained current of the additional low-voltage release load is within the capacity of one ship's service generator. Automatic sequential starting of low-voltage release controllers is acceptable to meet this paragraph.
(c) Low-voltage protection. Each motor controller must have low-voltage protection, except for the following motor controllers:
(1) A motor controller that has low-voltage release under paragraph (b) of this section.
(2) A motor controller for a motor of less than 2 horsepower (1.5 kW).
(d) Identification of controllers. (1) Each motor controller and motor control center must be marked externally with the following information:
(i) Manufacturer's name or identification.
(ii) Voltage.
(iii) Number of phases.
(iv) Current.
(v) kW (Horsepower).
(vi) Identification of motor being controlled.
(vii) Current rating of trip setting.
(2) Each controller must be provided with heat durable and permanent elementary wiring/schematic diagrams of the controller located on the door interior.
§ 111.70-5 - Heater circuits.
(a) If an enclosure for a motor, master switch, or other equipment has an electric heater inside the enclosure that is energized from a separate circuit, the heater circuit must be disconnected from its source of potential by a disconnect device independent of the enclosure containing the heater. The heater disconnecting device must be adjacent to the equipment disconnecting device. A fixed sign, warning the operator to open both devices, must be on the enclosure of the equipment disconnect device, except as in paragraph (b) of this section.
(b) If the location of the enclosure for a motor, master switch, or other equipment for deck machinery is remote from the motor and controller disconnect device, a sign must be fixed to the enclosure if the disconnect arrangement required by paragraph (a) of this section is not used. The sign must warn the operator of the presence of two sources of potential within the enclosure and show the location of the heater circuit disconnect device.
(c) Electric heaters installed within motor controllers and energized from a separate circuit must be disconnected in the same manner as required by paragraph (a) of this section or by § 111.70-7(d).
§ 111.70-7 - Remote control, interlock, and indicator circuits.
(a) Overcurrent protection. A conductor of a control, interlock, or indicator circuit of a motor controller must be protected against overcurrent unless:
(1) The conductor is wholly within the controller enclosure;
(2) The rating or setting of the branch circuit overcurrent device is not more than 300 percent of the current-carrying capacity of the control, interlock, or indicator circuit conductor;
(3) There is an overcurrent device in each side of the line that has a rating or setting of not more than 300 percent of the current-carrying capacity of the control, electrical interlock, or indicator circuit conductor, except if under operating conditions there is no appreciable difference in potential between the external conductors, overcurrent protection need only be at the supply of that side of the line; or
(4) The opening of the control, interlock, or indicator circuit creates a hazard.
Note:For overcurrent protection of steering gear control and indicator circuits, see Subpart 111.93 of this chapter.
(b) Accidental ground. The controller must be designed to prevent an accidental ground in a remote control circuit from causing the stop switches to fail to operate or causing the motor to start.
(c) Source of potential. The potential for a control, interlock, or indicator circuit must be derived from the load side of the motor and controller disconnect device, except if the control functions require circuits that must be common to two or more controllers, the switching arrangement in paragraph (d) of this section must be met.
(d) Switching. In the design of a control, interlock, or indicator circuit, all practicable steps must be taken to eliminate all but one source of power in an enclosure. If the control functions make it impracticable to energize a control interlock or indicator circuit from the load side of a motor and controller disconnect device and the voltage of the control, interlock, or indicator circuit is more than 24 volts, there must be one of the following alternative methods of switching:
(1) Each conductor of a control, interlock, or indicator circuit must be disconnected from all sources of potential by a disconnect device independent of the motor and controller disconnect device. The two independent devices must be adjacent to each other, and a fixed sign, warning the operator to open both devices to disconnect completely the motor and controller, must be on the exterior of the door of the main disconnect device.
(2) Each conductor of a control, interlock, or indicator circuit must be disconnected from all sources of power by a disconnect device actuated by the opening of the controller door, or the power must first be disconnected to allow opening of the door. The disconnect device and its connections, including each terminal block for terminating the vessel's wiring, must have no electrically uninsulated or unshielded surface. When this type of disconnect device is used for vital auxiliary circuits, a nameplate must be affixed to the vital auxiliary motor controller door that warns that opening the door will trip a vital auxiliary off-line.