MANUFACTURING TECHNICAL INSTRUCTIONS SAFETY Subject: DESIGN, MAINTENANCE AND INSPECTION OF SECONDARY ELECTRICAL DISTRIBUTION SYSTEMS

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1 DAIMLERCHRYSLER MANUFACTURING TECHNICAL INSTRUCTIONS SAFETY Subject: DESIGN, MAINTENANCE AND INSPECTION OF SECONDARY ELECTRICAL DISTRIBUTION SYSTEMS ISSUE DATE: 5/1/90 EFFECTIVE DATE: 2/4/92 REVIEW DATE: 2/11/2003 SERIES & NO: SMI I. PURPOSE To establish a procedure for maintenance and inspection of secondary power systems. REFERENCE National Electric Code (Latest Edition) Manufacturer's Equipment Specifications Federal and State Occupational Safety & Health Acts M.T.I. SMI-107, "Procedure for Neutralizing and Locking Out Energy Sources for Machinery, Equipment and Facilities Services" II. III. FUNCTIONS AFFECTED Advance Manufacturing Engineering Plant Facilities Engineering Plant Maintenance Employee Safety OPERATIONS AFFECTED DaimlerChrysler Corporation IV. INFORMATION For the purpose of this instruction, secondary distribution electrical systems shall be defined as electrical equipment rated 600 volts or less, excluding switchgear. Secondary distribution equipment shall include busway, cable tray, conduit, disconnects, fuses, power and receptacle panels, wire and cable, boxes and fittings, wireways, three phase transformers rated 300 kva or less and single phase transformers rated 37 1/2 kva or less, grounds, and receptacles. V. INSTRUCTIONS Electrical distribution equipment shall require scheduled annual preventative maintenance. However, periodic maintenance shall be required to remove dirt, clean up possible leakage of fluids, tighten loose connections, replace worn or frayed cables, etc. Sufficient access and working space shall be provided and maintained about all electrical equipment to provide safe operation and ease of maintenance. Inspection requirements can be found in this instruction for a majority of the distribution equipment found SMI-126, Page 1 of 6

2 in Chrysler Corporation facilities. VI. APPLICATION Electrical equipment shall only be used when the manufacturer's name, trademark, or other means of identification are provided. Other markings such as voltage, current, wattage, etc. shall be provided as required. Electrical distribution equipment requiring inspection must be isolated from the main power source. The local disconnect switch shall be locked in the "off" or "open" position prior to performing a maintenance function. A. Busway 1. Busway shall be installed in the building truss area where it can be located away from moving objects. 2. Busway shall be thermographically inspected at least once a year, preferrably every 3 months. Busway found with hot spots shall be inspected for loose connections, loose joints and loading. Joints shall be tightened per manufacturer's specified torque limits at least every six months. 3. Bus duct shall be supported per the manufacture's specification, at intervals not exceeding ten feet (1O') and shall be provided with sway bracing every fifty feet (50'), install additional sway bracing as needed. 4. Busway shall be labeled every fifty feet (50') specifying the operating voltage and substation source. Such labeling shall be capable of being identified from the plant floor level which preferably should be performed at the time of busway installation or plant renovation. This requirement is not retroactive for existing installations when such action generally could not be considered economically feasible. 5. Busway plugs shall be mechanically interlocked with the busway housing to prevent their installation or removal while the switch is in the "on" position. 6. Busway plugs not in use shall be disconnected from the bus duct and stored in an electrical room. B. Cable Tray 1. Cable tray shall be installed in the building truss area where it can be located away from moving objects. Aluminum cable tray installed outdoors shall be insulated from steel supports to avoid deterioration. 2. Cable tray shall be supported at intervals not exceeding twelve feet (12') and provided with sway bracing as needed. 3. Cable tray shall be grounded at intervals not exceeding one hundred feet (100'). 4. Cable in tray shall be tied at intervals not exceeding twelve feet (12'). 5. The minimum radius of all bends and offsets shall not be less than ten times the cable diameter. SMI-126, Page 2 of 6

3 C. Conduit 1. Conduit shall be rigid heavy wall steel of the hot dip galvanized type with a metallic corrosion-resisting coating on the interior and exterior. Conduit containing wires with 600 volts or less and above 8 feet from finish floor shall be electrical metallic tubing zinc coated steel with compression type couplings and connectors. Conduit smaller than 1/2" shall not be used. 2. Conduit shall be run exposed and shall not be put in concrete slab except where required for pits. 3. Conduit shall be installed parallel with or at right angles to building structures. 4. Conduit shall be supported at intervals not exceeding ten feet (1O') and at both sides of each opening or outlet. 5. Flexible steel conduit shall only be used to facilitate ease of installation of devices, such as motors and transformers. Flexible conduit shall not exceed three feet (3') in length. D. Disconnects E. Fuses 1. Disconnect switches shall be fused and sized accordingly. 2. The disconnect switch shall be interlocked with the panel cover so that the power must be de-energized prior to opening the panel cover. 3. The disconnect switch shall be labeled as to affected equipment and shall indicate "on" and "off" positions. The disconnect handle shall be mounted only in a vertical position, with the "up" position being the "on" position. 4. Disconnect switches shall be located where personnel cannot accidentally contact a live or suddenly moving part. 1. Fuses shall be labeled as to voltage, amperage and maximum short circuit current as tested by the fuse manufacturer. 2. Fuses shall not expel gas, vapor, liquid, flame or other particles upon action. 3. Fuses rated for 600 volts shall not be used on circuits rated 240 volts or less, so as to provide proper circuit protection. F. Power and Receptacle Panels 1. Panels shall be provided with a main disconnect for isolation of power. 2. A sheet metal cover shall be provided over the breaker compartments with openings for the operating handles only. 3. Each panel shall have a circuit diagram attached to the panel door. The schematic SMI-126, Page 3 of 6

4 shall show all connected loads. A nameplate shall be provided on the panel cover showing the maximum rated voltage. 4. Panels shall be installed in easily accessible areas. Materials shall not be stored in front of or against panel enclosures. Panels to be mounted on columns shall be protected from rolling equipment. G. Wire and Cable 1. Phasing of 480 volt, 3 phase devices shall be the same throughout a facility for all switchgear, bus, motor control centers, panels, etc volt wiring shall be run in a separate conduit from the 48O volt wiring. 120 volt wiring may only be run in the same conduit with the 480 volt motor wires from the starter panel providing control is limited to that motor only. 3. Conductor shall be run from terminal to terminal without any splices, except at individual devices that have pigtail leads. 4. Five conductor cords shall only be used to connect 120 colt devices where adjustment of location is required for ease of replacement such as limit, floor, and speed switches. The maximum length of cord shall be seven feet (7'). 5. Conductors shall be color coded as follows: a. Neutral - White b. Power - Black c. Control - Red d. D.C - Voltage - Blue e. Control interlock from external source - Yellow f. Ground - Green 6. Plugs and connectors shall be constructed and installed to guard against contact with live parts. They shall be capable of interrupting their rated output without hazard to the operator, and shall not be capable of insertion into a receptacle of a lower rating. All plugs shall be provided with a ground prong. 7. Cable constructed of interlocked armor shall be installed in cable tray. Cable shall be tied to tray at intervals not exceeding twelve feet(12'). Cable shall be checked for damage to the jacket, cracks, and improper splices. H. Boxes and Fittings 1. Boxes and fittings shall be made of code gauge sheet metal and shall be corrosion resistant. 2. Conductors entering boxes and fittings shall be protected from abrasion. Where boxes are installed with open wiring, conductors shall enter through insulating bushings. 3. Boxes and fittings shall be installed where the wiring contained in them can be readily accessible without removing any part of the building or excavating the earth. Boxes shall be installed on centers not exceeding one hundred feet (100'). 4. The front edge of boxes and fittings installed in walls or ceilings made of wood or other SMI-126, Page 4 of 6

5 combustible material shall be mounted flush with the finished surface. 5. Unused openings in boxes shall be effectively closed. All boxes shall be provided with covers made of the same thickness and material as specified for the walls of the box. 6. Boxes shall be supported independently of conduit and shall be rigidly secured in place. 7. Boxes shall be rectangular or octagonal having a flat bearing surface at each knockout. Boxes shall be sized in accordance with table 370-6(a) of the National Electric Code. Boxes other than those found in table 370-6(a) shall be marked with the manufacturer's name or trademark, and cubic inch capacity. 8. Covers of boxes having holes through which flexible cord pendants pass shall have a smooth, well-rounded surface. I. Wireways 1. Wireways shall be supplied with hinged or removable covers. 2. Wireways shall be supported at intervals not exceeding five feet(5'). 3. Wireways shall be marked so that their manufacturer's name or trademark is visible. J. Transformers 1. Transformers rated 3OO kva and less shall be of the dry type. 2. Transformers located in a Division 2 Hazardous Area shall have windings and terminal connections enclosed in a tight metal housing. 3. Transformers shall not be installed in areas where dust from magnesium, aluminum or other volatile metals are present. 4. The maximum surface temperature for a transformer operating at its full rating shall not exceed 120 degrees C. 5. Transformers shall be provided with a noncombustible moisture-resistant enclosure that provides protection from accidental insertion of foreign objects. 6. Transformers shall not be located where possible exposure to physical damage may occur. 7. Transformers shall be provided with a nameplate stating: manufacturer's name; rated volt-amps; frequency; and primary and secondary voltages. 8. Lifting holes shall be provided on two sides of the transformers as an integral part of the core. K. Grounds 1. Exposed non-current carrying metal parts of fixed equipment liable to be energized shall be grounded. SMI-126, Page 5 of 6

6 2. Supports for switching equipment shall be grounded. 3. Exposed non-current carrying metal parts of cords and plug connected equipment liable to be energized shall be grounded. 4. All service conductor enclosures such as raceways, when made of metal, shall be grounded. L. Receptacles 1. Power receptacles shall be of the interlocked combination type with a fused disconnect switch. The receptacle shall be interlocked with the switch to prevent the insertion or removal of a plug when the switch is in the "on" position. 2. Receptacles shall be provided with a cover and shall not have any exposed wiring. 3. Receptacles shall be provided with a ground and shall only used for their rated voltage. 4. All 240 volt and 480 volt outlets shall be labeled with their respective voltage to avoid confusion with a standard 120 volt outlet. SMI-126, Page 6 of 6