ELECTRICAL CODE REQUIREMENTS II MAXIMUM NUMBER OF CONDUCTORS IN A BOX The table below, based on clause 12-3034 of the Canadian Electrical Code, lists the maximum NUMBER of conductors permitted in a box. It is assumed that the box contains no more than 1 wire connector, and no fixture studs, hickeys or flush devices. Capacity per gang in3 (cm³) 4.5 (74) 5 (82) 8 (131) 10 (163) 11.5 (188) 12 (197) 12.5 (204) 14 (229) 14.5 (238) 15 (245) 15.7 (257) 16 (262) 16.5 (270) 18 (294) 18.5 (303) 20.25 (331) 21 (334) 22.25 (344) 24 (393) 25 (410) 27 (442) 30 (491) 36 (589) 37.5 (614) 42 (688) 39.5 (647) 50 (819) 52 (853) Box series DS 56111, OBEX 1100 1102, 775, EZ101 2018 3102 1104, 2104, 4204 2020, MBS 1304, 2304 1004, 1504, 54151, 55151 1204 3104 1110, 1111 1804, 3004 1151 MBS-HV 52151, 53151, 54171, 55171, MBD MBD-HV 54531 2104 (2 Gangs) 2304 (2 Gangs) 52171, 53171, 54541, 72151, 73151 54551 54551 54561, 72171, 73171 2304 (3 Gangs) 2104 (4 Gangs) 2304 (4 Gangs), GSB (2 Gangs) 14 Maximum NUMBER of Conductors* 12 10 AWG 3 3 5 6 7 8 8 9 9 10 10 10 11 12 12 13 14 14 16 16 18 20 24 24 28 26 33 34 AWG 2 2 4 5 6 6 7 8 8 8 8 9 9 10 10 11 12 12 13 14 15 17 20 20 24 21 28 29 * The maximum NUMBER of conductors is reduced in each of the following cases: - One conductor if the box contains one or more fixture studs or hickeys. - One conductor for every pair of wire connectors (no deduction for one wire connector, deduct one connector for 2 or 3 wire connectors, two conductors for 4 or 5 wire connectors, etc.). - Two conductors if the box contains one or more flush devices mounted on a single strap. If a flush device is greater than 1" thick, reduce the box capacity by 5 cubic inches X the thickness of the device. The maximum NUMBER of conductors listed is per gang. Multiply the NUMBER listed by the NUMBER of gangs (where applicable) to obtain the maximum NUMBER of conductors in the box. Refer to the Canadian Electrical Code for complete information. 1 cu. in. = 16.4 milliliter = 16.4 cubic centimeter 1 cubic centimeter = 1 milliliter = 0.061 cu. in. AWG 2 2 3 4 5 5 5 6 6 6 6 7 7 8 8 9 9 9 10 11 12 13 16 16 18 17 22 23 8 AWG - 1 2 3 4 4 4 5 5 5 5 5 6 6 6 7 7 8 8 9 9 10 13 13 15 17 18 18
