Cold Weather Catalog - Chromalox Precision Heat and Control

Heating CableSRM/ESelf-RegulatingMedium Temperature(cont’d.)Thermal Output Ratings on Insulated Metal Pipe 1242016SELF-REGULATINGHeat Output (W/Ft.)1284030 50 70 90 110 130 150 170 190 210 230 250 270 290 300(°F)Note 1 — Thermal output is determined per IEEE 515-2004 Standard for testing, designinstallation, and maintenance of electrical resistance heat tracing section 4.1.11Method C.Output Wattage at Alternate Voltages (W/Ft.)Model 208V% ChangeIn Output 220V% ChangeIn Output 277V% ChangeIn OutputSRM/E 3 2.31 -23 2.55 -15 3.90 +23SRM/E 5 3.85 -23 4.25 -15 6.45 +23SRM/E 8 6.4 -20 6.88 -14 10.24 +22SRM/E 10 8.3 -17 8.80 -12 12.50 +20SRM/E 15 12.75 -15 13.50 -10 18.45 +19SRM/E 20 17.6 -12 18.40 -8 24.40 +19Circuit Breaker Selection (Max. Circuit Lengths in Ft.)Cable50°F Start-Up (Ft.) 0°F Start-Up (Ft.) -20°F Start-Up (Ft.)Rating 15A 20A 30A 40A 50A 15A 20A 30A 40A 50A 15A 20A 30A 40A 50ASRM/E 3-1SRM/E 3-2285575385770NR780NRNRNRNR275540375750385780NRNRNRNR265525365740385780NRNRNRNRSRM/E 5-1SRM/E 5-2180360240480360720375750NRNR165325220430330645375750NRNR155310210415310620375750NRNRSRM/E 8-1SRM/E 8-2145285190380285575325650NRNR135255175345265520325650NRNR130245165335250490325650NRNRSRM/E 10-1SRM/E 10-295190125255190385250490NRNR90165110225175345250490NRNR85155100215170330245470250490SRM/E 15-1SRM/E 15-2701459519014529019038521042065120851751252701653602104206011580165120260150340210420SRM/E 20-1SRM/E 20-260115751551152301553051603505010065135105200140270160350459065130100195135255160335NR = Not Required. Maximum circuit length has been reached in a smaller breaker size.Note — Thermal magnetic circuit breakers are recommended since magnetic circuit breakers could "nuisance trip" at low temperature.89