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Notes

46 C.F.R. §§ 143.555–143.575

5 sections in range

§143.555. Electrical power sources, generators, and motors.

46 C.F.R. § 143.555

(a)
General requirements.
(1)
There must be a source of electrical power sufficient for:
(i)
All essential systems as defined by § 136.110 of this subchapter;
(ii)
Minimum conditions of habitability; and
(iii)
Other installed or portable systems and equipment.
(2)
Generators and motors must be suitably rated for the environment where they operate, marked with their respective ratings, and suitably protected against overcurrent.
(3)
A towing vessel, other than an excepted vessel, must have a backup or a second power source that has adequate capacity to supply power to essential alarms, lighting, radios, navigation equipment, and any other essential system identified by the cognizant OCMI or a TPO.
(b)
Specific requirements.
(1)
The owner or managing operator must complete a load analysis that shows that the electrical power source is sufficient to power the sum of connected loads described in paragraph (a)(1) of this section utilizing an appropriate load factor for each load. A record of the analysis must be retained by the owner or managing operator.
(2)
Installed generators and motors must have a data plate listing rated kilowatts and power factor (or current), voltage, and rated ambient temperature.
(3)
Generators must be provided with overcurrent protection no greater than 115 percent of their rated current and utilize a switchboard or distribution panel.
(4)
Motors must be provided with overcurrent protection that meets Parts I through VII, Article 430 of NFPA's National Electrical Code (NEC) (incorporated by reference, see § 136.112 of this subchapter). Steering motor circuits must be protected as per Part 4 Chapter 6 Section 2, Regulation 11 (except 11.7) ofABS Rules for Building and Classing Steel Vessels Under 90 Meters (295 feet) in Length (incorporated by reference, see § 136.112 of this subchapter).
(5)
Generators and motors installed in machinery spaces must be certified to operate in an ambient temperature of 50 °C or be derated, or it can be shown that 40 °C ambient temperature will not be exceeded in these spaces.
(6)
Each generator and motor, except a submersible-pump motor, must be in an accessible space which is adequately ventilated and as dry as practicable, and must be mounted above the bilges.
(7)
A generator driven by a main propulsion unit (such as a shaft generator) may be considered one of the power sources required by paragraph (a) of this section.
(8)
Other than excepted vessels, each towing vessel must be arranged so that the following essential loads can be energized from two independent sources of electricity:
(i)
High bilge level alarm required by § 143.230;
(ii)
Emergency egress lighting, unless the requirements of § 143.410(b)(1) or (2) are met;
(iii)
Navigation lights;
(iv)
Pilothouse lighting;
(v)
Engine room lighting;
(vi)
Any installed radios and navigation equipment as required by §§ 140.715 and 140.725;
(vii)
All distress alerting communications equipment listed in §§ 140.715 and 140.725;
(viii)
Any installed fire detection system; and
(ix)
Any essential system identified by the cognizant OCMI or TPO, if applicable.
(9)
If a battery is used as the second source of electricity required by paragraph (b)(8) of this section, it must be capable of supplying the loads for at least three hours. There must be a means to monitor the condition of the battery backup power source.
Notes, amendments, and revision history

Authority

Authority: 46 U.S.C. 3103, 3301, 3306, 3308, 3316, 8104, 8904; 33 CFR 1.05; DHS Delegation No. 0170.1.

Source

Source: USCG-2006-24412, 81 FR 40101, June 20, 2016, unless otherwise noted.

§143.560. Electrical distribution panels and switchboards.

46 C.F.R. § 143.560

(a)
Each distribution panel or switchboard on a towing vessel must be:
(1)
In a location that is accessible, as dry as practicable, adequately ventilated, and protected from falling debris and dripping or splashing water; and
(2)
Totally enclosed and of the dead-front type.
(b)
Each switchboard accessible from the rear must be constructed to prevent a person's accidental contact with energized parts.
(c)
Nonconductive mats or grating must be provided on the deck in front of each switchboard and, if it is accessible from the rear, on the deck behind the switchboard.
(d)
Each un-insulated current-carrying part must be mounted on noncombustible, nonabsorbent, and high-dielectric insulating material.
(e)
Equipment mounted on a door of an enclosure must be constructed or shielded so that a person will not come into accidental contact with energized parts.
Notes, amendments, and revision history

Authority

Authority: 46 U.S.C. 3103, 3301, 3306, 3308, 3316, 8104, 8904; 33 CFR 1.05; DHS Delegation No. 0170.1.

Source

Source: USCG-2006-24412, 81 FR 40101, June 20, 2016, unless otherwise noted.

§143.565. Electrical overcurrent protection other than generators and motors.

46 C.F.R. § 143.565

(a)
General requirement. Power and lighting circuits on towing vessels must be protected by suitable overcurrent protection.
(b)
Specific requirements.
(1)
Cable and wiring used in power and lighting circuits must have overcurrent protection that opens the circuit at the standard setting closest to 80 percent of the manufacturer's listed ampacity. Overcurrent protection setting exceptions allowed by NFPA's National Electrical Code (NEC), Article 240 (incorporated by reference, see § 136.112 of this subchapter) may be employed.
(2)
If the manufacturer's listed ampacity is not known, tables referenced in Article 310.15(B) of the NEC (incorporated by reference, see § 136.112 of this subchapter) must be used, assuming a temperature rating of 75 °C and an assumed temperature of 50 °C for machinery spaces and 40 °C for other spaces.
(3)
Overcurrent protection devices must be installed in a manner that will not open the path to ground in a circuit; only ungrounded conductors must be protected. Overcurrent protection must be coordinated such that an overcurrent situation is cleared by the circuit breaker or fuse nearest to the fault.
(4)
Each transformer must have protection against overcurrent that meets Article 450 of the NEC (incorporated by reference, see § 136.112 of this subchapter).
(5)
On a towing vessel, other than an excepted vessel as defined in § 136.110 of this subchapter, essential systems and non-essential systems must not be on the same circuit or share the same overcurrent protective device.
Notes, amendments, and revision history

Authority

Authority: 46 U.S.C. 3103, 3301, 3306, 3308, 3316, 8104, 8904; 33 CFR 1.05; DHS Delegation No. 0170.1.

Source

Source: USCG-2006-24412, 81 FR 40101, June 20, 2016, unless otherwise noted.

§143.570. Electrical grounding and ground detection.

46 C.F.R. § 143.570

(a)
An ungrounded distribution system must be provided with a ground detection system located at the main switchboard or distribution panel that provides continuous indication of circuit status to ground, with a provision to temporarily remove the indicating device from the reference ground.
(b)
A dual voltage or grounded electrical distribution system must have the neutral suitably grounded. There must be only one connection to ground, regardless of the number of power sources. This connection must be at the main switchboard or distribution panel.
(c)
On a metallic towing vessel, a grounded distribution system must be grounded to the hull. This grounded system must be connected to a common, non-aluminum ground plate. The ground plate must have only one connection to the main switchboard or distribution panel, and the connection must be readily accessible for examination.
(d)
On a nonmetallic towing vessel, all electrical equipment must be grounded to a common ground. Multiple ground plates bonded together are acceptable.
(e)
Each grounding conductor of a cable must be identified by one of the following means:
(1)
Green braid or green insulation; or
(2)
Stripping the insulation from the entire exposed length of the grounding conductor.
(f)
A towing vessel's hull may not carry current as a conductor, except for an impressed-current cathodic-protection system or a battery system used to start an engine.
(g)
Cable armor may not be used to ground electrical equipment or systems.
(h)
Each receptacle outlet and attachment plug for a portable lamp, tool, or similar apparatus operating at 100 or more volts must have a grounding pole and a grounding conductor in the portable cord.
(i)
In a grounded distribution system, only grounded, three-prong appliances may be used. This does not apply to double-insulated appliances or tools and appliances of 50 volts or less.
Notes, amendments, and revision history

Authority

Authority: 46 U.S.C. 3103, 3301, 3306, 3308, 3316, 8104, 8904; 33 CFR 1.05; DHS Delegation No. 0170.1.

Source

Source: USCG-2006-24412, 81 FR 40101, June 20, 2016, unless otherwise noted.

§143.575. Electrical conductors, connections, and equipment.

46 C.F.R. § 143.575

(a)
Each cable and wire on a towing vessel must be installed to meet the following requirements:
(1)
Each conductor must have sufficient current-carrying capacity for the circuit in which it is used.
(2)
Cable hangers for overhead and vertical cable runs must be installed with metal supports and retention devices at least every 48 inches.
(3)
Each wire and cable run must be installed in a manner to prevent contact with personnel, mechanical hazards, and leaking fluids. Wire and cable runs must not be installed in bilges, across a normal walking path, or less than 24 inches from the path of movable machinery (e.g., cranes, elevators, forktrucks, etc., where the machinery location can change) unless adequately protected.
(4)
Connections and terminations must be suitable for the installed conductors, and must retain the original electrical, mechanical, flame-retarding, and where necessary, fire-resisting properties of the conductor. If twist-on types of connectors are used, the connections must be made within an enclosure and the insulated cap of the connector must be secured to prevent loosening due to vibration. Twist-on type of connectors may not be used for making joints in cables, facilitating a conductor splice, or extending the length of a circuit.
(5)
Each cable and wire must be installed so as to avoid or reduce interference with radio reception and compass indication.
(6)
Each cable and wire must be protected from the weather.
(7)
Each cable and wire must be supported in order to avoid chafing or other damage.
(8)
Each cable and wire must be protected by metal coverings or other suitable means, if in areas subject to mechanical abuse.
(9)
Each cable and wire must be suitable for low temperature and high humidity, if installed in refrigerated compartments.
(10)
Each cable and wire must be located outside a tank, unless it supplies power to equipment in the tank.
(11)
If wire is installed in a tank, it must have sheathing or wire insulation compatible with the fluid in a tank.
(b)
Extension cords must not be used as a permanent connection to a source of electrical power.
(c)
Multi-outlet adapters (power strips) may not be connected to other adapters (“daisy-chained”), or otherwise used in a manner that could overload the capacity of a receptacle.
Notes, amendments, and revision history

Authority

Authority: 46 U.S.C. 3103, 3301, 3306, 3308, 3316, 8104, 8904; 33 CFR 1.05; DHS Delegation No. 0170.1.

Source

Source: USCG-2006-24412, 81 FR 40101, June 20, 2016, unless otherwise noted.