Machine Tool Wire Ampacity

Mtw stands for machine tool wire and as the name implies its primary uses are related to the wiring of machine tools appliances and control cabinets.

Machine tool wire ampacity.

2 sizes 18 awg 16 awg. 10 12 and 14awg are 19 strands all others are highly flexible stranding constructions. Machine tool wire mtw consists of stranded soft annealed copper conductors insulated with polyvinylchloride pvc. Our selection of mtw bare copper and tew tinned copper presents the best wire options for every function.

Certain sizes and colors are also available in 2500 foot reels. Mtw is ul rated for 600 volts. Voltage rating for all applications is 600 volts. Encore wire corporation size awg type mtw 600 volts gr i vw 1 ul or awm or c ul type tew ft1 listed.

Mtw is a machine tool wire with a bare copper conductor and pvc insulation that is available in a variety of colors for identification purposes. Ampacities are based on table 310 15 b 16 of the nec 2014 edition. Allowable ampacities of insulated conductors rated up to and including 2000 volts 60 c through 90 c 140 f through 194 f not more than three current carrying conductors in raceway cable or earth directly buried based on ambient temperature of 30 c 86 f. Wdt id gauge construction temp volt flame rating tinned copper stranding nom.

Mtw wire is sold in 500 foot spools. Is the higher ampacity determined by the physical characteristics or because the wiring is mostly run inside of control enclosures. Control cabinets in machine tool applica tions and in appliance wiring applications. Applications for machine tool wire include use with switchboards appliances electronic circuits and control cabinets and of course the wiring of machine tools.

Mtw wire tew wire pass the vw 1 flame test and are also moisture resistant. For use in accordance with the national jacket electrical code nec and nfpa standard 79. Where would i find ampacity tables for machine tool wire mtw other than in nfpa 79 1997. Weighing approximately 951 lbs mft these wires are rated for up to 600 volts and have different maximum temperature ratings.

Of strands insulation thickness overall diameter net weight awg kcm inches mm lbs kft 18strmtw 18 16 0 030 0 76 0 113 2 87 11 16strmtw 16 26 0 030 0 76 0 125 3 18 14 14strmtw 14 41 0 030 0 76 0 139 3 53 20. Why does mtw wire have a higher ampacity rating than standard stranded wire. It is a pvc hookup wire and although machine tool wire is qualified for many wiring applications it is a simply constructed wire that is made up of a highly stranded bare copper conductor. The above data is approximate and subject to normal manufacturing tolerances.

Conductor sizes 18 awg through 2 awg.