Cold Weather Catalog - Chromalox Precision Heat and Control

Heating CableDLIntegrated TemperatureControls (cont’d.)RTAS & RTAS-EP Ambient SensingRTAS is an ambient-sensing thermostat whichis generally used for freeze protection in ordinary(non-hazardous) areas. The thermostat ismounted through the end of the oblique sidedenclosure lid. In fact, because there is so muchroom in this model, multiple heating cables canbe terminated. The stainless steel sheathed,inverted bellows probe provides good sensitivity,resulting in more accurate control.RTAS-EP is a modifi ed version of the RTASwhich utilizes a hermetically sealed switch.Since this switch has no arcing contacts, it canbe used in Division 2 Hazardous Areas.SpecificationsTemp. Setpoint Range — 0 to 225°F (-18 to107°C) for RTAS/RTAS-EPMicroswitch ® Rating — 22 Amps SPDT forRTAS; 11 Amps, RTAS-EPScale Division — 10°F (5.6°C)Max. Sensor Exposure Temp. — 250°F (121°C)Sensor Dimensions — 9/16" Dia. x 3" LongOperating Ambient Temp. Range — -40°F to160°F (-40 to 71°C)Factory Preset and Calibrated — 40°FHEG3"(7.6 cm)6.25"(15.9 cm)FA5.25"(13.3 cm)LBKCJ4.25"(10.8 cm)IDConstructionABCDEFGHIJKStrategically placed cable entries allowmaximum fl exibility for insulation(Heating cable cut away for clarity).Stainless steel tiedown support providespositive attachment to pipes. 1Heavy duty support legs give stable pipemounting and provide conduit clearancefor applications with up to three inchesof insulation.Opening for 3/4" (20 mm) conduit hub. 1Stainless steel sheath temperaturesensor.Cable grommets provide water-tight sealbetween base, box and cable. Use GRSRwith all self-regulating cables. Use GRCWwith constant wattage cables. One of eachgrommet included in kit. See table belowfor spare grommets.Three position terminal block for easywiring.Power wiring entry. Conduit hub notincluded.Gasket provides water-tight seal betweenbox and lid. It is affi xed to the lid andholds the mounting hardware duringassembly.Thermostat switch.Setpoint adjustment knob.LSetpoint indicator.Note 1 — Refer to DL & EL General ApplicationAccessories at the end of this section.Spare GrommetsPCNGRS RTD/Capillary type 385000GR0 Blank 385019GRSR Self-regulating cable type 389714GRCW Constant wattage cable type 389722Ordering InformationModelPCNSwitch Rating(Amps/Volts)Max. Continuous Exposure Temp. Max. Intermittent Exposure Temp. Wt.(Lbs.)°F °C °F °CRTAS 389589 22A @ 120 - 480 400 200 500 260 2RTAS-EP 389597 11A @ 120 - 250 400 200 500 260 2Stock Status: S = stock AS = assembly stock NS = non-stockTo Order—Specify model, PCN and quantity.144