RTDs. Offered by. Phone: (203) Fax: (203) Specialists in Valves, Controls, Pneumatics, Fluid Measurement

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1 RTDs Offered by Phone: (203) Fax: (203) Specialists in Valves, Controls, Pneumatics, Fluid Measurement

2 NS RTD s I- Theory of Operation n RTD s basis of operation lies in a common property of any metal, the relationship between its temperature and the resistance to the flow of electrical currents through it. Once the characteristics of this relationship were established, a few metals found their way into common use in RTD s. These are mainly, platinum, nickel and copper. Platinum s resistance changes relative to temperature, reflected in an RTD s TCR (temperature coefficient of resistance), is about Ω/Ω/ C sufficient for high sensitivity to temperature at the usual 100Ω nominal resistance. Linearity of the resistance/ temperature relationship is also quite good and well defined. nd finally, accuracy is excellent due to platinum s stability and resistance to contamination, which also results in a wide recommended operating temperature range of -200 to 550 C. The most common RTD, a platinum RTD as described above but modified for industrial applications, has a platinum alloy element (usually platinum - 5% rhodium) with a TCR of Ω/Ω/ C and shares most of the characteristics of the platinum RTD with added durability and a recommended temperature range extended to 650 C. Nickel and copper are also occasionally used as resistive elements in RTD applications. Nickel has the largest TCR at Ω/Ω/ C for very high sensitivity but its linearity is very poor. Copper is the most linear, but has a limited temperature range. II RTD Element Parameters n RTD s sensing element has several parameters from which to select depending on the application: Material (specification) Platinum (IEC-751) Platinum (JIS C ) Copper Nickel TCR Ω/Ω/ C Ω/Ω/ C Ω/Ω/ C Ω/Ω/ C Nominal Resistance 100, 500, or 0 C 100, 500, or 0 C C C ccuracy To To ±( T ) C ±( T ) C n/a n/a Temp to 850 C -250 to 650 C -90 to 250 C -90 to 300 C These are the most common values, additional TCR s, nominal resistances, and accuracy s are widely available III- RTD Lead Configuration n additional consideration in the designation of RTD parameters is the lead configuration. Four possibilities exist: In the two-wire configuration, lead wire resistance can t be accounted for. This design is employed when accuracy is of less importance than other mechanical and/or electrical design parameters. Note, using an element with a high nominal resistance can minimize accuracy problems. pproximate error induced by lead wire at room temperature for platinum RTD s Lead length (24 WG) Ω nominal 0 C 0.13 C 0.27 C 0.53 C 1.33 C 500Ω nominal 0 C 0.03 C 0.05 C 0.11 C 0.27 C 1000Ω nominal 0 C 0.01 C 0.03 C 0.05 C 0.13 C The most common configuration for industrial RTD s is the three-wire. Lead wire resistance is compensated for by the addition of a third leg. ccuracy is dependent on the matched resistances of the lead wires, errors induced by this configuration normally amount to less than 0.05 C In the four-wire configuration, lead wire resistance is compensated for by the addition of third and fourth legs. ccuracy is no longer dependent on the matched resistances of the lead wires. This configuration also has better immunity to noise, thermoelectric effects, and contact resistance problems. n uncommon variation of the three-wire configuration, with similar performance, except uses a separate circuit for the compensating loop

3 National asic Sensor IV- RTD Permissible Deviation Tolerance classifications and data for RTD elements are available for platinum RTD s only. The two most frequently specified classes defined by the industry standard IEC-751 (for platinum RTD s with a temperature coefficient of resistance of Ω/Ω/ C) are Class and Class. The tolerances in C are calculated as follows: Class : ±( T ) C Class : ±( T ) C V- Industry Standards for RTD s Several industry standards for platinum RTD s exist today, the most commonly encountered are: For platinum RTD s with a temperature coefficient of resistance of Ω/Ω/ C: European and International IEC-751 S EN DIN EN merican STM-1137 Japanese JIS C Commonly encountered obsolete standards for this TCR are DIN43760 and S1904 For platinum RTD s with a temperature coefficient of resistance of Ω/Ω/ C: Old Japanese standard JIS C Same tolerance classifications as IEC-751 The above Resistance Tolerances (in Ohms) are for RTD s with a nominal resistance of 0 C, for 500Ω and 1000Ω RTD s multiply the resistance tolerance by 5 or 10 times, respectively. nationalbasicsensor.com 59

4 NS RTD s RTD with SS & Leadwires 2 1 2" C 10E Designates RTD with SS and Leadwires Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /8 (.125) 3/16 (.188) 1/4 (.250) 3/8 (.375) Step 8 - Leads Step 9 - in Inches Step 10 - Leadwires TT Teflon TO Teflon with SS overbraid TG Fiberglass Step 11 - Leadwire C in Inches Step 12 - P Pigtails PL Pigtails with spade lugs PLX Pigtails with spade lugs & x connector M Standard plug F Standard jack SPC Standard plug with mating connector MM Miniature plug FM Miniature jack MPC Miniature plug with mating connector *4 wire available with pigtails only Step 13 - Mounting Z No mounting fitting Compression Fitting rass Compression Stainless Compression Stainless Readjustable Mounting Size NPT C13 SC13 RC13 1/8 C17 SC17 RC17 1/4 C27 SC27 RC27 1/2 Step 14 - Step Code Style Series Resistance ccuracy Temperature Transition Leads C Mounting Fitting Example 10E S T TT P - Z - Z

5 National asic Sensor RTD with SS & Transition Leadwires 2 1 2" C 10L Designates RTD with SS and Transition Leadwires Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /8 (.125) 3/16 (.188) 1/4 (.250) 3/8 (.375) Step 8 - Leads Step 9 - in Inches Step Code Style Series Resistance ccuracy Temperature Step 10 - Leadwires TT Teflon TO Teflon with SS overbraid T Teflon with flex armor TG Fiberglass G Fiberglass with flex armor Step 11 - Leadwire C in Inches Step 12 - P Pigtails PL Pigtails with spade lugs PLX Pigtails with spade lugs & x connector M Standard plug F Standard jack SPC Standard plug with mating connector MM Miniature plug FM Miniature jack MPC Miniature plug with mating connector *4 wire available with pigtails only Step 13 - Mounting Z No mounting fitting Compression Fitting rass Compression Stainless Compression Transition Leads Stainless Readjustable C Mounting Size Mounting Fitting Example 10L S T T P - Z - NST NPT C13 SC13 RC13 1/8 C17 SC17 RC17 1/4 C27 SC27 RC27 1/2 Step 14 - nationalbasicsensor.com 61

6 NS RTD s RTD with SS, Leadwires & Welded Hex Fitting 2 1 2" C Weld 10F Designates RTD with SS, Leadwires and Welded Hex Fitting Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /8 (.125) 3/16 (.188) 1/4 (.250) 3/8 (.375) Step 9 - in Inches Step 10 - Leadwires TT Teflon TG Fiberglass Step 11 - Leadwire C in Inches Step 12 - P Pigtails PL Pigtails with spade lugs PLX Pigtails with spade lugs & x connector M Standard plug F Standard jack SPC Standard plug with mating connector MM Miniature plug FM Miniature jack MPC Miniature plug with mating connector *4 wire available with pigtails only Step 13 - Mounting SD27 1/2 NPT x 1/2 NPT SS hex fitting SD34 1/2 NPT x 3/4 NPT process SS hex fitting *Silver braze for 1/8 OD Step 14 - Step 8 - Leads 62 Step Code Style Series Resistance ccuracy Temperature Transition Leads C Mounting Fitting Example 10F S T TT P - SD27 - SST

7 National asic Sensor RTD with SS, Leadwires & Spring-loaded Hex Fitting 2 1 2" C (relaxed insertion depth) 10G Designates RTD with SS, Leadwires and Spring-loaded Hex Fitting Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /8 (.125) 3/16 (.188) 1/4 (.250) Step 9 - in Inches Step 10 - Leadwires TT Teflon TG Fiberglass Step 11 - Leadwire C in Inches Step 12 - P Pigtails PL Pigtails with spade lugs PLX Pigtails with spade lugs & x connector M Standard plug F Standard jack SPC Standard plug with mating connector MM Miniature plug FM Miniature jack MPC Miniature plug with mating connector *4 wire available with pigtails only Step 13 - Mounting SL27 1/2 NPT x 1/2 NPT SS hex fitting - spring loaded Step 14 - Step 8 - Leads Step Code Style Series Resistance ccuracy Temperature Transition Leads C Mounting Fitting Example 10G S T TT P - SL27 - Z nationalbasicsensor.com 63

8 NS RTD s RTD with SS & Connection Head 10C Designates RTD with SS and Connection Head Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /8 (.125) 3/16 (.188) 1/4 (.250) 3/8 (.375) Step 8 - Leads Step 9 - in Inches Step 10 - W luminum screw cover head Cast iron screw cover head N Nylon screw cover head PS White polypropylene screw cover head SS Stainless steel screw cover head F luminum flip top head X Explosion proof head D Delrin screw cover head Miniature closed head Step 11 - Mounting Z No mounting fitting Compression Fitting rass Compression Stainless Compression Stainless Readjustable Mounting Size NPT C13 SC13 RC13 1/8 C17 SC17 RC17 1/4 C27 SC27 RC27 1/2 Step 12 - TM 4-20 m head mounted transmitter *Certain connection heads not available with transmitter 64 Step Code Style Series Resistance ccuracy Temperature Mounting Fitting Example 10C S T F - Z - Z

9 National asic Sensor RTD with SS, Connection Head & Welded Hex Fitting Weld 10W Designates RTD with SS, Connection Head and Welded Hex Fitting Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step 6 - Step 8 - Leads Step 9 - in Inches Step 10 - W luminum screw cover head Cast iron screw cover head N Nylon screw cover head PS White polypropylene screw cover head SS Stainless steel screw cover head F luminum flip top head X Explosion proof head Step 11 - Mounting SD27 1/2 NPT x 1/2 NPT SS hex fitting SD34 1/2 NPT x 3/4 NPT process SS hex fitting *Silver braze for 1/8 OD Step 12 - TM 4-20 m head mounted transmitter /8 (.125) 3/16 (.188) 1/4 (.250) 3/8 (.375) Step Code Style Series Resistance ccuracy Temperature Mounting Fitting Example 10W S T SS - SD27 - Z nationalbasicsensor.com 65

10 NS RTD s RTD with SS, Connection Head & Spring-Loaded Hex Fitting (relaxed insertion depth) 10S Designates RTD with SS, Connection Head and Spring-Loaded Hex Fitting Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step 6 - Step 8 - Leads Step 9 - in Inches Step 10 - W luminum screw cover head Cast iron screw cover head N Nylon screw cover head PS White polypropylene screw cover head SS Stainless steel screw cover head F luminum flip top head X Explosion proof head Step 11 - Mounting SL27 1/2 NPT x 1/2 NPT SS hex fitting - spring loaded Step 12 - TM 4-20 m head mounted transmitter /8 (.125) 3/16 (.188) 1/4 (.250) 66 Step Code Style Series Resistance ccuracy Temperature Mounting Fitting Example 10S P T F - SL27 - Z

11 National asic Sensor RTD with SS, Connection Head & Spring-Loaded 1/2 NPT Nipple (relaxed insertion depth) 10N Designates RTD with SS, Connection Head and Spring-Loaded 1/2 NPT Nipple Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /4 (.250) 3/8 (.375) Step 8 - Leads Step 9 - in Inches Step 10 - W luminum screw cover head Cast iron screw cover head N Nylon screw cover head PS White polypropylene screw cover head SS Stainless steel screw cover head F luminum flip top head X Explosion proof head Step 11 - Nipple 3 3 length 4 4 length 6 6 length Step 12 - Nipple Material SS Stainless steel I lack iron Step 13 - TM 4-20 m head mounted transmitter Step Code Style Series Resistance ccuracy Temperature Nipple Material Example 10N P T SS - TM nationalbasicsensor.com 67

12 NS RTD s RTD with SS, Connection Head & Spring-Loaded 1/2 NPT Nipple-Union Nipple (relaxed insertion depth) 10U Designates RTD with SS, Connection Head and Spring-Loaded 1/2 NPT Nipple - Union - Nipple Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /4 (.250) 3/8 (.375) Step 8 - Leads Step 9 - in Inches Step 10 - W luminum screw cover head Cast iron screw cover head N Nylon screw cover head PS White polypropylene screw cover head SS Stainless steel screw cover head F luminum flip top head X Explosion proof head Step 11 - Nipple-Union-Nipple 3 3 length 4 4 length 6 6 length Step 12 - Nipple-Union-Nipple Material SS Stainless steel I lack iron Step 13 - TM 4-20 m head mounted transmitter 68 Step Code Style Series Resistance ccuracy Temperature Nipple Material Example 10U P T SS - TM

13 RTD with SS, Spring & 6 Pigtails National asic Sensor 6 " 10V Designates RTD with SS, Spring and 6 Pigtails Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation /4 (.250) 3/8 (.375) Step 8 - Leads Step 9 - in Inches Step 10 - Pigtails P 6 pigtails *other lengths available Step 11 - Step 6 - Step Code Style Series Resistance ccuracy Temperature Example 10V P T P - Z Pigtails nationalbasicsensor.com 69

14 NS RTD s RTD with SS & Connector U U G 10Q Designates RTD with SS and Connector Platinum sensor lpha coefficient of Platinum sensor lpha of Copper sensor lpha of Nickel sensor lpha of Step 4 - ccuracy S Standard Class P Premium Class Step 5 - Temperature Code Temperature Insulation Step /8 (.125) 3/16 (.188) 1/4 (.250) 3/8 (.375) * element not available in 1/8 OD Step 8 - Leads D T 2 wire 3 wire Step 9 - in Inches Step 10 - M Standard plug F Standard jack SPC Standard plug with mating connector MM Miniature plug FM Miniature jack MPC Miniature plug with mating connector Step 11 - Mounting Z No mounting fitting Compression Fitting rass Compression Stainless Compression Stainless Readjustable Mounting Size NPT C13 SC13 RC13 1/8 C17 SC17 RC17 1/4 C27 SC27 RC27 1/2 Step 12 - Step Code Style Series Resistance ccuracy Temperature Mounting Fitting Example 10Q S T M - Z - SST

15 Cuttable RTD National asic Sensor The Series 10T Cuttable RTD is a 1/4 OD Stainless Steel Tube. This RTD can be cut onsite to your desired length by use of a tube cutter. 6" Class ccuracy Max Temperature = 400 F Teflon Leadwire Max Temperature = 1000 F Fiberglass Leadwire Other Configurations vailable - Consult Factory 10T Designates Cuttable RTD Platinum sensor lpha of Platinum sensor lpha of Step 6 - in Inches Step Code Style Series Resistance Cuttable Probes Can e Shortened to 3 Minimum Using a Tube Cutter Internally Sealed to Prevent Moisture Penetration Step 4 - Leads Step 7 - Leadwires TT Teflon TG Fiberglass Leadwires Example 10T T TT Spring Loaded Nipple For 1/4 OD Cuttable Thermocouple 1/2 x 1/2 NPT 316 Stainless Steel vailable with Viton O Ring 3" Step 5 - Leads Tube Cutter The Model is specifically designed for cuttable RTD s. Easily Cuts 1/8 5/8 Tubing Descriptions Catalog Price Standard Fitting 5SL27-8 $25.00 With Viton O Ring 5SL27-80R $30.00 Catalog Price $24.00 nationalbasicsensor.com 71

16 NS RTD s PIE 311 RTD Calibrator Source and Read Multiple RTD Curves plus Ohms Platinum 100 W: a=1.3850, , ; Platinum 1000 W: a=1.3850, Copper 10 & 50 W; Nickel 110 & 120 W; 0.00 to W Resolution to 0.1 deg. F & C; ccurate to 0.2 deg. utomatically Detect 2,3 & 4 Wire Connections Verify RTD Temperature & output Includes: Rubber boot (4) lkaline batteries Certification of Calibration Carrying case Catalog Price 311 $1, Pc. RTD Wire Install Tool Kit w/case 1 Long nose mini pliers 1 Diagonal cutting pliers 3 Mini Slotted screwdrivers 3 Mini Phillips screwdrivers 1 Carrying case Catalog Price 80058SK $

17 Offered by Phone: (203) Fax: (203) Specialists in Valves, Controls, Pneumatics, Fluid Measurement