The basic transducer may be selected with either of four mounting configurations and with or without provisions for water cooling of the transducer body.  The listed radiometers are provided with gas purging to keep the radiation-transmitting window clean. When the purge provision is included, the window is installed internally and is not an accessory. Basic transducers can be converted to unpurged radiometers by addition of a window attachment, but the standard purged radiometers cannot be converted to basic transducers.  

Standard Mounting Configurations Illustrated Below.  There is the smooth body with flange, the threaded body with flange, the smooth body without flange, and the threaded body without flange.  All mounting flanges are 1.73″ dia. with 0.150″ dia. mounting holes equally spaced on a 1.375″ dia. bolt circle.  Water-cooling tubes (when specified) and gas purge tubes are 1/8″ dia.  SST. All tubes are 4″ long.  (Other tube diameters, lengths, and fittings are available.)  All threaded bodies have 1-12UNF-2A threads. 

• Standard Ranges Available: Full scale design heat flux level: 4000, 3000, 2500, 2000, 1500, 1000, 500, 250, 200, 100, 50, 30, 25, 20, 15, 10, 5, 2, 1, 0.5, 0.2 Btu/(ft²⋅s).  (Custom ranges available.) 

• Output Signal: linear output, 10 millivolts nominal at full range. 

• Maximum Allowable Operating Body Temperature:  400 °F. 

• Overrange Capability: to 150% range for 2-1000 Btu/(ft²⋅s) ranges. 

• Maximum Non-Linearity: ±2% of full range. 

• Repeatability: ±1/2% 

• Calibration Expanded Uncertainty: ±3% for ranges to 250 Btu/(ft²⋅s), coverage factor k=2, for approximate 95% confidence level. 

• Sensor Absorptance (Hemispherical): Gardon gages, .92, nominal, from 0.6 to 15.0 µm.  Thermopiles, .95, nominal, from 0.6 to 15.0 µm. 

• Spectrum Transmitted By Sapphire Window (When used): 85%nominal from 0.15 to 5.0 µm.  Other window materials are optional. 

• Lead Wire:  24 AWG stranded copper twisted pair, Teflon insulation over each, braided copper shield, Teflon jacket overall, 36″ standard length with stripped ends. (The optional body thermocouple wire is 24 AWG Teflon/Teflon insulated duplex solid conductor.) 

• Time Constant: (63.2% response to a step radiant heat Input)

  • 250 to 4000 Btu/(ft²⋅s): less than 50 ms

  • 50 to 200 Btu/(ft²⋅s): less than 100 ms

  • 2 to 30 Btu/(ft²⋅s): less than 250 ms 

• Sensor Type: (Standard, options available)

  • 5 to 4000 Btu/(ft²⋅s): Gardon Gage (Except S-B for 64P-5 models)

  • 0.2 to 4 Btu/(ft²⋅s): Schmidt-Boelter (Schmidt-Boelter sensors are also available as an option from 5 to 100 Btu/(ft²⋅s) ranges. 

• Nominal Impedance: (with standard leadwire)

  • Less than 10 ohms on Gardon Gages

  • Less than 250 ohms on Schmidt-Boelter Gages. 

• Heat Capacity of Uncooled Units: Energy that can be absorbed by transducer in an adiabatic installation (defined as all surfaces perfectly thermally insulated except for 1-inch diameter sensor face) before exceeding the 400 °F maximum body temperature limitation: Model without water cooling provisions:  6.2 Btu, Models with water cooling provisions but without water: 4.2 Btu 

• Maximum Purge Gas Pressure: 150 psi over ambient