TABLE 2-PORTABLE CORD AMPACITIES-600 VOLTS (AMPERES PER CONDUCTOR BASED ON 60 °C. COPPER TEMPERATURE-40 °C. AMBIENT) TABLE 3-PORTABLE POWER CABLE AMPACITIES 601 TO 5,000 VOLTS (AMPERES PER CONDUCTOR BASED ON 75 °C. COPPER TEMPERATURE-40 °C. AMBIENT) TABLE 4-NOMINAL DIAMETERS OF ROUND CABLES WITH TOLERANCES IN INCHES-600 VOLTS 85 65 85 100 115 130 145 170 195 220 245 275 305 TABLE 5-NOMINAL DIMENSIONS OF FLAT CABLES WITH TOLERANCES IN INCHES-600 VOLTS TABLE 5-NOMINAL DIMENSIONS OF FLAT CABLES WITH TOLERANCES IN INCHES-600 VOLTS— TABLE 6-NOMINAL DIAMETERS OF HEAVY JACKETED CORDS WITH TOLERANCES IN INCHES-600 Type G-GC (nonshielded) 2,000 volts Conductor size-AWG or MCM TABLE 7-NOMINAL DIAMETERS OF THREE-CONDUCTOR PORTABLE POWER CABLES WITH TABLE 8-FUSE RATINGS OR INSTANTANEOUS SETTING OF CIRCUIT BREAKERS FOR SHORT-CIRCUIT PROTECTION OF PORTABLE CABLES AND CORDS TABLE 8-FUSE RATINGS OR INSTANTANEOUS SETTING OF CIRCUIT BREAKERS FOR SHORT-CIRCUIT PROTECTION OF PORTABLE CABLES AND CORDS-Continued Higher circuit-breaker settings may be permitted for special applications when justified. TABLE 9-SPECIFICATIONS FOR PORTABLE CABLES LONGER THAN 500 FEET 1 'Fuses shall not be used for short-circuit protection of these cables. Circuit breakers shall be used with the instantaneous trip settings not to exceed the values given in Table 8. [33 FR 4660, Mar. 19, 1968; 33 FR 6345, Apr. 26, 1968, as amended at 42 FR 8373, Feb. 10, 1977] APPENDIX II TO SUBPART D OF PART 18 Figure 1 Typical layout drawing of a machine. 2 LIST OF FIGURES Title Sample bill of material (to accompany layout drawing shown on figure 1) 3 Material to be included with the operating instructions on or with the wiring diagram submitted to each customer. 4 Sample factory inspection form. 5 Typical plane joint. 6 Typical combination joint. 7 Typical threaded joint. 8 Typical threaded straight stuffing box and packing gland lead entrance with provision for hose conduit. 9 Typical slip-fit straight-type and angle-type stuffing box and packing gland lead entrance. 10 Typical slip-fit angle-type stuffing box and packing gland lead entrance and typical plug for spare lead entrance hole. To retain "permissibility" of this equipment the following conditions shall be satisfied: 1. General safety. Frequent inspection shall be made. All electrical parts, including the portable cable and wiring, shall be kept in a safe condition. There shall be no openings into the casings of the electrical parts. A permissible distribution box shall be used for connection to the power circuit unless connection is made in fresh intake air. To maintain the overload protection on direct-current machines, the ungrounded conductor of the portable cable shall be connected to the proper terminal. The machine frame shall be effectively grounded. The power wires shall not be used for grounding except in conjunction with diode(s) or equivalent. The operating voltage should match the voltage rating of the motor(s). enclosures 2. Servicing. Explosion-proof shall be restored to the state of original safety with respect to all flame arresting paths, lead entrances, etc., following disassembly for repair or rebuilding, whether by the owner or an independent shop. 3. Fastenings. All bolts, nuts, screws, and other means of fastening, and also threaded covers, shall be in place, properly tightened and secured. 4. Renewals and repairs. Inspections, repairs, or renewals of electrical parts shall not be made unless the portable cable is disconnected from the circuit furnishing power, and the cable shall not be connected again until all parts are properly reassembled. Special care shall be taken in making renewals or repairs. Leave no parts off. Use replacement parts exactly like those furnished by the manufacturer. When any lead entrance is disturbed, the original leads or exact duplicates thereof shall be used and stuffing boxes shall be repacked in the approved manner. 5. Cable requirements. A flame-resistant portable cable bearing a MSHA assigned identification number, adequately protected by an automatic circuit-interrupting device By removal of all sharp corners or edges? Is wiring separated from hydraulic components? Is an adequate insulated strain clamp provided for the portable cable? Are all packing glands properly packed so that %-inch clearance remains between packing nut and stuffing box? Are lockwashers (or equivalent) provided for all explosion-proof enclosure fastenings? Are all plane joints securely fastened so that an 0.005-inch feeler gage cannot be inserted? Are all threaded covers secured? Are all electrical connections secure and properly insulated where nec essary? NOTE: Add appropriate material for each explosion-proof enclosure when more than a motor and starter are on a machine. |