Current Industrial Reports United States Department of Commerce Economic and Statistics Administration Bureau of the Census SWITCHGEAR, SWITCHBOARD APPARATUS, RELAYS, AND INDUSTRIAL CONTROLS - 1996 MA36A(96)-1 Issued September 23, 1997 Information on the scope of the survey, survey methodology, and historical facts can be found in the 1995 Manufacturing Profiles issued June 1997. These data are also available through the U.S. Department of Commerce and STAT-USA Electronic Bulletin Board by Subscription. To access, dial 202-482-3870 and follow the prompts to register; or call 202-482-1986, for further information. Inquiries: Address inquiries concerning these data to U.S. Department of Commerce, Bureau of the Census, Manufacturing and Construction Division, Washington,D.C. 20233, or call Wanda L.W. Sledd, (301) 457-4790. SUMMARY OF FINDINGS During 1996, the total value of shipments of switchgear and switchboard apparatus was $6.4 billion, up 5 percent from the 1995 value of $6.1 billion. The 1996 shipments include power circuit breakers valued at $420.7 million, a decrease of 5 percent from 1995; low voltage panelboards, valued at $2.1 billion, an increase of 6 percent from 1995; fuses and fuse equipment, valued at $522.2 million, an increase of 4 percent from 1995; molded case circuit breakers, valued at $1.2 billion, an increase of 4 percent from 1995; duct, valued at $254.5 million, an increase of 6 percent from 1995; and switchgear valued at $1.9 billion, an increase of 6 percent from 1995. During 1996, the total value of shipments of relays and industrial controls was $9.2 billion, up 4 percent from the 1995 value of $8.8 billion. The 1996 shipments include general-purpose relays valued at $806.7 million, a decrease of 0.2 percent from 1995; specific-purpose industrial controls, valued at $3.5 billion, an increase of 4 percent from 1995; general-purpose industrial controls, valued at $4.4 billion, an increase of 5 percent from 1995; and motor controller accessories valued at $497.2 million, a decrease of 1 percent from 1995. Table 1. Value of Shipments of Switchgear, Switchboard Apparatus, Relays, and Industrial Controls: 1991 to 1996 [Millions of unadjusted dollars] Product code Product description 1996 1995 1994 1993 1992 1991 36132 Power circuit breakers.......... 420.7 442.9 550.9 520.8 480.8 368.5 36133 Low-voltage panelboards....... 2,152.8 2,025.4 1,750.8 1,687.1 1531.1 1,642.6 36134 Fuses and fuse equipment......... 522.2 r/500.1 382.1 319.9 412.8 409.4 36135 Molded case circuit breakers.. 1,218.3 1,173.4 1,132.9 1,009.8 954.7 916.6 36136 Duct, 1,000 volts and under......... 254.5 238.5 227.9 200.1 189.1 184.2 36139 Switchgear (except ducts)............ 1,864.0 1,758.3 1,663.7 1581.3 1615 1,398.1 36251 Relays, general purpose........... 806.7 r/808.1 804.0 750.6 781.5 772.0 36252 Specific purpose industrial controls.......... 3,467.1 3,312.4 2,747.9 2321.6 1915.7 1,992.7 36253 General purpose industrial controls.......... 4,426.9 4,189.2 3,840.3 3326.3 2778.2 2,878.6 36254 Motor controller accessories and parts for industrial controls.......... 497.2 503.3 511.6 476.4 447.9 434.1 r/ Revised by 5 percent or more from previously published data. Table 2. Shipments of Switchgear, Switchboard Apparatus, Relays, and Industrial Controls: 1996 and 1995 [Quantity in number of units. Value in thousands of dollars] Number of 1996 1995 Product Product description com- code panies Quantity Value Quantity Value 3613 -- Switchgear and switchboard apparatus....................(NA) (X) 6,432,344 (X) 6,138,496 36132 - Power circuit breakers, all voltages..................... 34 (X) 420,680 (X) 442,889 36132 16 Power circuit breakers, sold seperately for use in metal-clad switchgear, oil and oiless, over 1,000 volts (number of breakers)................. 11 3,304 42,908 r/3,762 39,120 36132 17 Parts for power circuit breakers for use in metal clad switchgear 1/........ 6 (X) (D) (X) (D) 36132 21 Power circuit breakers, free standing, oil and oiless, from 15.5 kV through 800 kV and above, (number of breakers)...... 8 3,238 147,652 3,459 166,373 36132 22 Parts for power circuit breakers, free standing, oil and oilless, from 15.5 kV through 800 kV and above 1/.............. 3 (X) 12,602 (X) 12,320 36132 26 Power circuit breakers, sold seperately in individual enclosures and/or for use in low- voltage switchgear, 1,000 volts and below, excluding molded case circuit breakers (number of breakers) 2/.............. 9 (D) (D) (D) (D) 36132 27 Parts for power circuit breakers in individual enclosures and/or for use in low-voltage switchgear, 1,000 volts and below, excluding molded case circuit breakers.......... 6 (X) 1,290 (X) 2,023 36132 31 All other power circuit breakers, sold separately oil and oilless, network protectors and automatic circuit reclosers 2/...... 8 1,806,112 174,534 1,813,739 174,914 36132 32 Parts for all other power circuit breakers, oil and oiless, network protectors and automatic circuit reclosers......... 14 (X) 41,694 (X) r/48,139 36133 - Low voltage panelboards, distribution boards, and other switching and interupting devices, 1,000 volts and below.............. 134 (X) 2,152,758 (X) 2,025,387 Panelboards, including enclosing cabinets: 36133 11 Fusible, including combination switch fuse.... 47 1,702,163 170,257 1,674,342 141,082 36133 12 Circuit breaker............. 54 1,066,908 483,370 r/ 879,034 406,501 Distribution switchboards: 36133 15 Fusible..................... 31 33,193 106,284 r/ 29,837 101,391 36133 17 Circuit breaker............. 45 82,878 321,007 r/ 80,156 r/ 293,838 36133 19 Other, including theater switchboards............... 9 21,934 11,770 24,054 10,671 Switches (except switches commonly known as snap, toggle, and rotary switches and switch devices intended primarily to be used with electric motor controls): Knife switches, enclosed 36133 21 Heavy duty................ 11 1,794,738 170,864 1,742,520 172,755 36133 22 General duty.............. 8 1,567,989 71,328 1,514,487 66,155 36133 24 Enclosed fusible, service entrance and branch circuit cutouts.......... 9 930,081 25,038 841,799 19,815 36133 26 Circuit breaker type....... 18 9,184,735 275,810 9,179,504 294,481 Load centers: 36133 32 Grouped metering panels (combinations of two or more meters and related switching units with overcurrent protection associated with each meter, including accessory components, excluding single socket load combinations)....... 16 582,000 39,878 487,060 34,805 36133 33 Other switches, excluding snap, bolted, toggle, push, etc., including open knife switches, motor contact, motor disconnect, meter service equipment other than metermounting, and test devices.................. 24 (X) 203,740 (X) r/192,933 36133 98 Other low voltage switch- gear apparatus.............. 36 (X) 273,412 (X) r/290,960 36134 - Fuses and fuse equipment, under 2,300 volts (except power distribution cutouts).. 24 (X) 522,201 (X) r/500,110 36134 31 Nonrenewable plug fuses 3/. 2 (X) (D) (X) 4,240 36134 51 Nonrenewable cartridge fuses...................... 10 (X) 254,408 (X) r/234,791 36134 71 Renewable plug and cartridg fueses including renewable links 3/........ 3 (X) (D) (X) (D) 36134 93 Other fuses and open fuse material, including cutouts, clips, bases, etc. 3/.................... 22 (X) 267,793 (X) r/261,079 36135 - Molded case circuit breakers, 1,000 volts and under........ 36 149,875,013 1,218,269 r/152,547,052 1,173,358 Industrial type, assembled as complete units in supporting and enclosing housing of insulated materials, with or without accessories or attachments: 36135 14 With ground fault detection capability 4/.. 13 (D) (D) (S) 23,577 36135 16 Without ground fault detection capability 4/.. 18 27,879,463 632,215 29,277,392 574,271 Residential or light duty type-(primarily) for load center application - assembled as complete units in supporting and enclosing housing of insulating materials: 36135 18 With ground fault detection capability 5/.. 7 (D) (D) 985,705 29,184 36135 19 Without ground fault detection capability 5/.. 7 51,980,001 288,322 58,228,182 287,717 36135 31 Individually enclosed industrial type, excluding panelboards and busway plugs...................... 15 9,185,662 15,747 8,155,130 17,143 Other molded case circuit breakers: 36135 91 Marine and Navy type 6/... 4 (D) (D) (D) (D) 36135 92 Aircraft and aerospace 6/. 6 1,293,889 119,165 1,067,767 114,567 36135 93 Automotive 7/............. 2 (D) (D) (D) (D) 36135 94 Electronic 7/............. 5 53,719,792 138,104 r/47,579,273 103,971 36135 95 All other types........... 12 (S) 24,716 (S) 22,928 36136 - Duct, including plug-in units and accessories, 1,000 volts and under, consisting of enclosed sectionalized prefabricated bus bars rated 20 amperes or more and associated structures and fittings................. 23 1,454,970 254,460 2,293,932 238,479 36136 11 Busways 8/................... 21 (D) (D) 1,641,519 233,855 36136 31 Trolly-type and lighting distribution duct 8/........ 3 1,454,970 254,460 652,413 4,624 36139 - Switchgear (except ducts).....129 (X) 1,863,976 (X) 1,758,273 36139 07 Automatic and manual control panels (Generators, transformers, feed-controls, etc........................ 69 (X) 301,866 (X) 308,989 36139 09 Metal-clad switchgear (using power circuit breakers, oil and oiless, all voltages above 1,000 volts, up to and including 38 kV, excluding load interrupter switchgear.42 (X) 378,542 (X) 303,126 36139 10 Metal-enclosed load interrupter switchgear assemblies, all voltages, including parts........... 37 (X) 138,807 (X) 129,378 36139 13 Metal-enclosed low-voltage power circuit breaker switchgear assemblies 1,000 volts and below, including parts and excluding load interrupter switchgear..... 29 (X) 165,116 (X) 142,316 36139 17 Metal-enclosed bus bars when sold seperately, above 1,000 volts, including isolated, segregated, nonsegregated and cable bus bars....................... 17 (X) 24,681 (X) 32,368 Power switching equipment, 2,300 volts and over, including attachments, auxiliaries accessories, but excluding power fuses, sold separately. Also includes single phase circuit reclosers: 36139 41 Outdoor, excluding structures............... 28 (X) 336,424 (X) 312,324 36139 45 Indoor.................... 9 (X) 3,324 (X) 1,873 36139 51 Power fuses and fuse links for 2,300 volts and over, a.c. service, excluding distribution cutouts 9/.... 12 (X) (D) (X) (D) 36139 81 Power and ground connectors generally used in substation construction 9/. 6 (X) 143,344 (X) 135,268 36139 91 Overhead transmission and distibution connectors (clamps, taps, terminals, and splice.s).............. 6 (X) 41,729 (X) 41,141 36139 93 Transmission and distribution connectors, n.e.c., including underground deadends, hot line taps, stirrups, repair sleeves, etc. 10/.......... 6 (X) (D) (X) (D) 36139 83 Distribution cutouts........ 9 (X) 84,888 (X) 103,067 36139 98 Other switchgear devices including regulators and miscellaneous switchboard devices (for sale separately) 10/............ 25 (X) 245,255 (X) r/248,423 3625 -- Relays and industrial controls:....................(NA) (X) 9,197,782 (X) 8,813,083 36251 - General purpose and other relays.......................119 (X) 806,658 (X) r/808,121 36251 01 Industrial control relays (all voltages), n.e.c....... 44 82,281,972 261,953 r/88,669,458 r/260,544 General purpose electromechanical relays: Over 100 MW actuating power and sealed (Either hermetically or environmental): 36251 03 0 through 2.0 amps contact rating 11/............. 8 (D) (D) (D) (D) 36251 04 Over 2.0 through 10.0 amps contact rating 11/..... 17 888,551 27,806 r/1,971,832 r/24,045 36251 05 Over 10.0 amps contact rating................. 7 16,238,122 33,103 11,632,708 31,885 Over 100 MW actuating power and not sealed: 36251 02 0 through 10.0 amps contact rating.................. 13 1,339,791 13,750 2,801,349 r/15,703 36251 10 Over 10.0 amps contact rating 12/.............. 12 (D) (D) (D) (D) 36251 11 0 through 100 MW actuating power (Both sealed and not sealed) 12/.............. 2 1,250,927 10,082 1,488,628 9,744 Miniature printed circuit mounted electromechanical relays (Excluding reed relays) (Profile height 1/2" max.): Sealed (Either hermetically or environmentally): 36251 12 0 through 2.0 amps contact rating................. 5 (D) (D) 2,859,003 3,591 36251 15 Over 2.0 amps contact rating................. 4 (D) (D) (D) (D) 36251 20 Not sealed .............. 5 (D) (D) (D) (D) DIP or SIP footprint 36251 19 Sealed (Either hermetically or environmentally)..... 2 (D) (D) (D) (D) Telephone relays, all types: 36251 22 Sealed (either hermetically or environmentally)..... 4 (S) 976 648,744 1,038 36251 23 Not sealed............... 5 50,986 578 32,008 471 36251 30 General purpose solid-state relays, pure solid-state and hybrid solid-state (Excluding time delay).... 12 1,343,522 14,946 4,244,317 19,611 High performance military/ aerospace/aircraft relays and contactors (Generally pertaining to Mil-R5757, 6106, 19523, 25108, and 39016): 36251 31 Round and square can multipole airframe relays and contactors (both sealed and not sealed), all sizes................ 6 109,287 28,388 r/102,269 r/19,354 Crystal can types (sealed): 36251 32 Larger than full size... 5 344,030 21,539 291,541 19,900 36251 33 Full size............... 5 174,140 12,522 151,661 10,541 36251 37 Half size and smaller, including TO-5 package) 13/........... 4 (D) (D) (D) (D) 36251 52 RF, antenna and coaxial relays (Sealed and not sealed)(Excluding reed relays) 13/.............. 6 1,945,980 55,975 1,472,513 44,474 Reed relays: Dry reed: 36251 59 Miniature size (glass length less than .85 inches).. 10 17,744,582 34,585 22,809,642 37,132 36251 61 Standard size 14/....... 6 (D) (D) (D) (D) 36251 66 Mercury wetted reed 14/... 6 (D) (D) (D) (D) 36251 69 Stepping switches, stepping and impulse relays 14/..... 3 (D) (D) (D) (D) 36251 75 Switchgear and protective relays 14/................. 6 586,406 19,533 r/549,805 30,811 Timing relays (Timers): 36251 79 Solid-state/EMR combination.24 930,420 26,436 1,002,467 30,600 36251 81 Solid-state-pure........... 15 250,357 11,050 r/276,661 r/10,844 36251 82 All other timing relays (timers)including pneumatic, motor driven, electronic, etc....................... 14 421,461 18,096 951,363 25,026 36251 92 All other general purpose and special purpose relays, n.e.c....................... 25 (X) 163,485 (X) r/157,931 36251 96 Parts for general purpose and special purpose relays, sold separately)............ 11 (X) 28,308 (X) r/34,515 36252 - Specific purpose industrial controls.....................246 (X) 3,467,092 (X) 3,312,429 36252 45 U.S. Coast Guard, Navy, and Marine auxillary controls and accessories............ 22 75,612 130,539 78,965 124,897 36252 47 Metal mill controls and accessories (all voltages). 8 (D) (D) (D) (D) 36252 48 Crane and hoist controls, constant and adjustable voltage including operator's desks and stations................... 18 44,290 124,622 r/41,163 101,339 36252 49 Definite purpose contactors and starters (600 volts and less).................. 18 11,797,782 149,940 10,694,742 152,869 Machine tool applications (motion controllers): Stand-alone controls for numerically controlled machine tools: 36252 51 Computer numerical controls (CNC); positioning (point- to-point).............. 11 9,449 22,262 (S) 20,221 36252 55 Computer numerical controls (CNC); continuous path (contouring)........... 13 34,329 268,566 31,469 219,850 36252 57 Robotic controls........ 2 (D) (D) (D) (D) 36252 58 Other stand-alone motion controls............... 13 23,967 67,299 26,899 61,387 36252 60 Subordinate motion controls................. 11 88,772 14,190 84,237 14,841 36252 71 Programmable controllers, sold separately............ 62 4,816,048 1,234,345 4,445,039 1,201,058 36252 76 Other specific or special purpose a.c. and d.c. controllers, other definite purpose devices....................154 (X) 1,367,001 (X) r/1,338,102 36253 - General purpose industrial controls and power circuit devices......................268 (X) 4,426,872 (X) 4,189,187 General purpose controls: 36253 01 Ac full voltage non- combination magnetic starters (1,000 volts or less)...................... 23 1,153,398 154,851 1,312,410 169,382 Ac full voltage combination magnetic starters (1,000 volts or less): 36253 03 Combination starters, (less pumping panels)...... 21 176,347 75,526 216,181 85,785 36253 05 Pumping panels ............. 20 38,997 30,054 40,486 29,101 36253 06 Disconnect switches (600 volts or less)............. 18 2,022,225 58,429 2,030,558 56,241 Ac full voltage manual controllers, (1,000 volts or less): 36253 23 Designed and rated to U.S. National Standards (NEMA) 15/........................ 10 (D) (D) (D) (D) 36253 25 Designed and rated to International Standards (IEC) 15/................... 7 1,321,845 72,660 1,047,170 70,611 Ac contactors, 1,000 volts or less, excluding controls for packaged adjustable speed drives and synchronous motor control: 36253 27 Designed and rated to U.S. National Standards, (NEMA). 15 1,100,922 70,964 r/956,544 59,340 36253 29 Designed and rated to International Standards (IEC)...................... 13 1,918,596 60,104 1,993,071 r/56,960 36253 14 AC reduced voltage controls, 1,000 volts or less, excluding synchronous motor starters............. 22 80,167 59,024 r/84,968 r/62,104 36253 15 Synchronous motor starters 1,000 volts or less, including both full and reduced voltage............ 5 1,749 1,422 1,407 1,087 36253 16 Motor control centers, 1,000 volts or less.............. 33 (X) 423,258 (X) 418,930 36253 18 Starters and contactors for squirrel cage and wound rotor and synchronous and non-synchronous motors, over 1,000-7,200 volts, air break, vacuum, and oil immersed................... 11 69,764 85,605 65,585 80,661 36253 21 Brakes and clutches......... 19 1,138,134 66,827 872,058 61,480 36253 34 Digital readout systems, including dial or plugboard type....................... 22 7,868 10,590 10,026 10,446 Presence sensors and motion measurement devices: Limit switches (positioning sensors): 36253 32 Electromechanical positioning sensors........ 28 (X) 137,998 (X) 138,712 36253 33 Movement sensors............ 17 (X) 35,815 (X) 36,074 Solid-state positioning sensors: 36253 35 Non-optical proximity sensors.................... 16 (X) 82,667 (X) r/80,460 36253 36 Optical proximity senors.... 17 (X) 133,408 (X) 129,090 36253 37 All other pilot circuit devices, excluding relays and limit switches......... 12 (X) 26,619 (X) r/20,943 36253 38 DC power circuit devices (all voltages)............. 10 (X) 54,347 (X) 58,171 36253 39 Other control sensors (all voltages).................. 18 (X) 126,660 (X) 116,771 Pushbuttons and pushbutton stations but excluding operato,r's desks and stations: 36253 42 Pushbuttons, 18mm and smaller 16/................ 10 (X) 15,903 (X) (D) 36253 46 Pushbuttons, 19mm to 29mm 16/........................ 16 (X) 50,885 (X) 61,612 36253 48 Pushbuttons, 30mm and larger..................... 21 (X) 241,897 (X) 233,593 36253 81 Rheostats and resistors (except for electronic applications) sold separately, n.e.c.......... 13 (X) 22,001 (X) 34,826 Controls for adjustable speed drives, including electronic and nonelectric and operators's desks and stations: 36253 83 Controls for Ac packaged drives..................... 33 529,525 404,307 353,041 315,888 36253 84 Controls for Dc packaged drives..................... 26 246,144 155,241 r/261,503 r/134,821 36253 85 Ac drives systems........... 31 67,634 233,876 r/69,150 r/198,670 36253 86 Dc drives systems........... 26 376,533 162,079 753,129 171,285 36253 98 Solid-state motor controllers (all voltages). 51 3,586,173 277,016 r/3,957,211 r/264,771 36253 99 All other general industry devices and systems........101 (X) 1,096,839 (X) 1,031,372 36254 - Motor controller accessories and parts for industrial controls.................... 131 (X) 497,160 (X) 503,346 36254 91 Motor controller accessories, including those items which are sold separately, but become part of a motor controller. Includes overload relays, auxilliary contacts, heater elements, mechanical interlocks, control transformers, kits to add push buttons, selector switches, pilot lights, separate controller enclosure fittings, reset mechanisms, etc., excluding motor circuit switches sold separately................. 40 (X) 144,728 (X) 149,595 36254 97 Parts for industrial contro1s................... 13 (X) 352,432 (X) 353,751 - Represents zero. D Withheld to avoid disclosing data for individual companies. X Not applicable. NA Not available. N.e.c. Not elsewhere classified. r/ Revised by percent or more from previously published data. S Does not meet publication standards. 1/ Data for product code 36132 17 are included with product code 36132 22 to avoid disclosing data for individual companies. 2/ Data for product code 36132 26 are included with product code 36132 31 to avoid disclosing data for individual companies. 3/ Data for product codes 36134 31 and 36134 71 are included with product code 36134 93 to avoid disclosing data for individual companies. 4/ For 1996, data for product code 36135 14 are included with product code 36135 16 to avoid disclosing data for individual companies. 5/ For 1996, data for product code 36135 18 are included with product code 36135 19 to avoid disclosing data for individual companies. 6/ Data for product code 36135 91 are included with product code 36135 92 to avoid disclosing data for individual companies. 7/ Data for product code 36135 93 are included with product code 36135 94 to avoid disclosing data for individual companies. 8/ For 1996, data for product code 36136 11 are included with product code 36136 31 to avoid disclosing data for individual companies. 9/ Data for product code 36139 51 are included with product code 36139 81 to avoid disclosing data for individual companies. 10/ Data for product code 36139 93 are included with product code 36139 98 to avoid disclosing data for individual companies. 11/ Data for product code 36251 03 are included with product code 36251 04 to avoid disclosing data for individual companies. 12/ Data for product code 36251 10 are included with product code 36251 11 to avoid disclosing data for individual companies. 13/ Data for product code 36251 37 are included with product code 36251 52 to avoid disclosing data for individual companies. 14/ Data for product codes 36251 61, 36251 66, and 36251 69 are included with product code 36251 75 to avoid disclosing data for individual companies. 15/ Data for product code 36253 23 are included with product code 36253 25 to avoid disclosing data for individual companies. 16/ For 1995, data for product code 36253 42 are included with product code 36253 46 to avoid disclosing data for individual companies. Table 3. Shipments, Exports, Imports, and Apparent Consumption of Switchgear, Switchboard Apparatus, Relays, and Industrial Controls: 1996 and 1995 [Value in thousands of dollars] Exports of Manufacturers domestic Imports Product description shipments merchandise for Product (value f.o.b. (value at consump- code plant) port) 1/ tion 2/ 1996 36132 16, 21, Power circuit breakers............ 365,094 125,667 2,550,101 26, 31 36132 17, 22, Parts for power circuit breakers.. 55,586 160,877 1,707,053 27, 32 36133 11, 12, Low voltage panelboards and 15, 17, 19 distribution boards.............. 1,092,688 126,683 4,426,096 36133 21, 22 Knife switches.................... 242,192 2,793 99,658 36134 00 Fuses and fuse equipment, under 2,300 volts...................... 522,201 131,419 1,922,842 36135 00 Molded case circuit breakers, 1,000 volts and under............ 1,218,269 92,281 2,922,672 36136 00 Duct, including plug-in units and accessories...................... 254,460 39,007 292,056 36139 07, 09, Switchgear and switchgear 10, 13, 17, assemblies 3/.................... (D) (D) (D) 41, 45, 83, 98 36139 51 Power fuses and fuse links, 2,300 volts and over................... (D) (D) (D) 36139 81, 91, Power and ground connectors; and 93 transmission and distribution connectors 3/.................... 1,863,976 270,272 4,408,984 36251 01, 03, Relays............................ 750,360 460,285 20,929,854 04, 05, 02, 10, 11, 12, 15, 20, 30, 31, 32, 33, 37, 52, 59, 61, 66, 69, 75, 81, 82, 92 36252 51, 55, Controls for numerically controlled machine tools..................... 290,828 25,112 2,573,519 36252 71 Programmable controllers........... 1,234,345 116,090 8,832,260 36253 01, 03, Motor starters..................... 261,853 37,851 1,196,796 05, 15 36253 16 Motor control centers, 1,000 volts or less........................... 423,258 53,197 838,268 36253 21 Brakes and clutches................ 66,827 22,503 1,708,468 36253 32, 33, Limit switches..................... 173,813 9,351 642,502 36253 81 Rheostats and resistors............ 22,001 4,649 688,744 1995 36132 16, 21, Power circuit breakers............ 380,407 117,773 2,779,947 26, 31 36132 17, 22, Parts for power circuit breakers.. r/62,482 (NA) 2,008,304 27, 32 36133 11, 12, Low voltage panelboards and 15, 17, 19 distribution boards.............. 953,483 (NA) 4,183,587 36133 21, 22 Knife switches.................... 238,910 (NA) 66,139 36134 00 Fuses and fuse equipment, under 2,300 volts...................... r/500,110 110,343 2,183,991 36135 00 Molded case circuit breakers, 1,000 volts and under............ 1,173,358 98,674 3,149,743 36136 00 Duct, including plug-in units and accessories...................... 238,479 31,117 159,232 36139 07, 09, Switchgear and switchgear 10, 13, 17, assemblies 3/.................... (D) (D) (D) 41, 45, 83, 98 36139 51 Power fuses and fuse links, 2,300 volts and over 3/................ (D) (D) (D) 36139 81, 91, Power and ground connectors; and 93 transmission and distribution connectors 3/.................... 1,758,273 32,918 4,830,795 36251 01, 03, Relays............................ r/741,497 502,849 23,938,819 04, 05, 02, 10, 11, 12, 15, 20, 30, 31, 32, 33, 37, 52, 59, 61, 66, 69, 75, 81, 82, 92 36252 51, 55, Controls for numerically controlled machine tools......... 240,071 (NA) 3,240,446 36252 71 Programmable controllers.......... 1,201,058 (NA) 9,715,424 36253 01, 03, Motor starters.................... 285,355 (NA) 1,300,244 05, 15 36253 16 Motor control centers, 1,000 volts or less.......................... 418,930 (NA) 901,530 36253 21 Brakes and clutches............... 61,480 19,751 1,792,337 36253 32, 33 Limit switches.................... 174,786 (NA) (NA) 36253 81 Rheostats and resistors........... 34,826 2,053 28,080 D Withheld to avoid disclosing data for individual companies. NA Not available. r/ Reviised by 5 percent or more from previously published data. 1/ Source: U.S. Bureau of the Census report EM 545, U.S.Exports. 2/ Source: U.S. Bureau of the Census report IM 145, U.S.Imports for Consumption. 3/ Data for switchgear and switchgear assemblies; and power fuses and fuse links; combined with power and ground connectors; and transmission and distribution connectors to avoid disclosing data for individual companies. Table 4. Comparison of Standard Industrial Classification-Based Product Codes with Schedule B Export, Numbers, and HTSUSA Import Numbers: 1996 Product Product description Export Import code number 1/ number 2/ 36132 16, 21, Power circuit breakers 8535.21.0000 8535.21.0000 26, 31 8535.29.0020 8535.29.0020 8535.29.0040 8535.29.0040 8536.20.0040 8536.20.0040 36132 17, 22, Parts for power circuit breakers 8538.90.8020 8538.90.8020 27, 32 36133 11, 12, Low voltage panelboards and 8537.10.9050 8537.10.9050 15, 17 distribution boards 36133 21, 22 Knife switches 8536.50.8045 8536.50.8045 36133 32, 98 Grouped metering panels, including 8537.10.9020 8537.10.9020 accessory components and other low voltage switchgear apparatus 36134 00 Fuses and fuse equipment, under 8535.10.0040 8535.10.0040 2,300 volts 8536.10.0020 8536.10.0020 8536.10.0040 8536.10.0040 36135 00 Molded case circuit breakers, 1,000 8536.20.0020 8536.20.0020 volts and under 36136 00 Duct, including plug-in units and 8536.90.0010 8536.90.0010 accessories 36139 07, 09, Switchgear, including switchgear 8537.20.0020 8537.20.0020 10, 13, assemblies and power switching m5 41, 45, equipment, excluding power fuses 83 36139 51 Power fuses and fuse links, 2,300 8535.10.0020 8535.10.0020 volts and over 36139 81, 91, Power and ground connectors; and 8535.90.8040 8535.90.8040 93 transmission and distribution connectors, n.e.c. 36251 01, 03, Relays 8536.41.0005 8536.41.0005 04, 05, 8536.41.0020 8536.41.0020 02, 10, 8536.41.0030 8536.41.0030 11, 12, 8536.41.0045 8536.41.0045 15, 20, 8536.41.0050 8536.41.0050 30, 31, 8536.41.0060 8536.41.0060 32, 33, 8536.49.0050 8536.49.0050 37, 52, 8536.49.0055 8536.49.0055 59, 61, 8536.49.0065 8536.49.0065 66, 69, 8536.49.0075 8536.49.0075 75, 81, 8536.49.0080 8536.49.0080 82, 92 36252 51, 55 Controls for numerically controlled 8537.10.9030 8537.10.9030 machine tools 36252 71 Programmable controllers 8537.10.9060 8537.10.9060 36253 01, 03, Motor starters 8536.50.4000 8536.50.4000 05, 15 36253 16 Motor control centers, 1,000 volts 8537.10.6000 8537.10.6000 or less 36253 21 Brakes and clutches 8505.20.0000 8505.20.0000 36253 32, 33 Limit switches 8536.50.8055 8536.50.8055 36253 81 Rheostats and resistors 8533.40.0040 8533.40.8040 8533.40.8040 1/ Source: 1996 edition, "Harmonized System-Based Schedule B, Statistical Classification of Domestic and Foreign Commodities Exported from the United States." 2/ Source: "Harmonized Tariff Schedule of the United States, Annotated (1996)."  36253 16 Motor control centers, 1,000 volts or less.......................... 418,930