Edwards APG200-XM Active Pirani Vacuum Gauge, No set Point, NW16, KF16 Flange, Atmosphere Down to 3.75x10-4 Torr, Analog output 0-10V. Edwards Part Number D1G1011100, (Replaces APG100-XM Part Number: D02601000). The Edwards APG200-XM Active Linear Pirani Vacuum Gauge contains a NW16, KF16 vacuum flange, is compact for easy installation, has a linear output, and a user replaceable tube sensor. The new Edwards gauges are compatible with all Edwards TIC, ADC, TAG instrument controllers and other active gauge controllers and displays. They are also CSA, C/US approved as well as fully RoHS compliant due to their lead-free construction. They measure pressure from atmosphere down to 3.75x10-4 Torr. The signal cables and TIC vacuum gauge controllers are sold separately. These Edwards APG200-XM Active Pirani vacuum gauges with standard Tungsten/Rhenium filaments and NW16 vacuum flange with Edwards part number D1G1011100. The APG200 is available in three versions: M, LC, and MP series. The M series contains standard Tungsten/Rhenium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The LC version contains corrosive resistance Platinum/Iridium filaments, it can measure pressure from atmosphere down to 7.5x10-5 Torr, and is also suitable for use in corrosive applications. The MP series contains Platinum/Rhodium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The instruction manual for these Edwards APG200 series gauges is available in PDF format below. The APG200 can be mounted in any orientation however the gauge tubes are individually factory calibrated in nitrogen while vertical. For correct pressure indication in your chosen gauge orientation, the gauge should be recalibrated at atmospheric pressure. Edwards recommends mounting the gauge tube vertical in order to minimize the build up of process particulates and condensable vapors within the gauge. The APG200 is calibrated for use in nitrogen, and will read correctly with dry air, oxygen and carbon monoxide. For any other gas type a conversion is required in order to obtain the correct pressure reading, common gases: nitrogen, argon, carbon dioxide, helium, krypton and neon. Features Include: Easy Access to signal cable with compact enclosure Sensor bakeable to 150°C (300°F) and sensor is user replaceable Adjustable set point for simple process control and interlocking Remote calibration possible Pressure range 10-4 Torr Background On Pirani and Convection Enhanced Pirani GaugesPirani vacuum gauges can be classified as a thermal conductivity gauge being very similar to the thermocouple gauge where the resistance of the heated wire is measured to determine vacuum pressure. A Pirani gauge is designed to measure the resistance imbalance where the heated filament forms one of the arms of a Wheatstone bridge circuit. As the vacuum pressure increases, gas molecules transport heat away from the filament, and the resistance of the pressure sensor will move to a lower value which unbalances the circuit. The vacuum pressure is therefore calculated from the pressure induced imbalance in the Wheatstone bridge circuit. Just as with the thermocouple gauges, thermal conductivity by molecular collisions increases linearly with pressure over the 0.001 to 1 Torr pressure range. However, the heat removal becomes non-linear as the pressure is further increased into the viscous flow regime, where gas-gas collision can reorient molecules back towards the heated wire. Molecules have to collide many times before they reach the outer body of the sensor (the thermal sink). The convection-enhanced Pirani gauges take advantage of the convention current inside the sensor to extend its pressure measurement range all the way to atmospheric pressure. The Pirani gauge is an indirect pressure measurement sensors where measured readings are gas-type dependent. Some caution should be advised from the facts that heavier gases have poor heat transfer rates and that the standard convention-enhanced Pirani gauges are calibrated for N2 (basically the same calibration as Air). This could lead to dangerous overpressure conditions when back filling a vacuum systems with a heavier gas like argon. The danger arises if the vacuum system operator does not correct the gauge display reading for the correct gas-type, for example, a standard gauge calibrated for N2, displays 24 Torr when the chamber is at 760 Torr of argon. The operator would be fooled into thinking that the chamber was still under vacuum and continue to increase the system to a critical over-pressured state. Another source of error can be produced if the convection-enhanced Pirani gauge is not mounted correctly, most commercial sensors require that they are mounted parallel to the ground. This keeps the convention current inside the sensor flowing in the designed direction (errors of 20% or more can easily be introduced if the convention-enhanced Pirani sensor is not mount horizontally). Rapid evacuation of these convection-enhanced Pirani sensors will produce significant measurement error for a short period of several seconds. As the rapidly pumped gases expand, the removal of heat from the pressure sensor filament is not a normal convection current but is instead driven by forced convection. While the vacuum pressure is dropping rapidly the gases expand and cool, this provides a secondary pathway for removing heat from the hot sensor wire. The convection-enhanced Pirani gauge can falsely display high pressures up to 1000 Torr during system evacuation. Once the flow of gases is stopped the pressure reading will again stabilize to a realistic measured value. For these reasons, convection-enhanced Pirani gauges are not well suited for measuring pressure changes under dynamic pumping conditions. Overall, the convection-enhanced Pirani is a popular cost effective rough vacuum pressure gauge which can measures from Atmosphere to 1x10-4 Torr with those measurements below 1 Torr being most accurate.

Edwards APG200-XM Active Pirani Vacuum Gauge NW25, KF25 Flange. 10-3 Torr. Edwards Part Number D1G1021100. (APG200-XM PN: D1G1021100 Replaces APG100-XM PN: D02602000). The Edwards APG200-XM Active Pirani Vacuum Gauge contains a NW25, KF25 vacuum flange, is compact for easy installation, has a linear output, and a user replaceable tube sensor. The new Edwards gauges are compatible with all Edwards TIC, ADC, TAG instrument controllers and other active gauge controllers and displays. They are also CSA, C/US approved as well as fully RoHS compliant due to their lead-free construction. They measure pressure from 1000 down to 10-3 Torr. The signal cables and TIC vacuum gauge controllers are sold separately. The instruction manual for these Edwards APG200 series gauges is available in PDF format below. The APG200 is available in two versions: the ’M’ version (contains standard Tungsten/Rhenium filaments) can measure pressure down to 10-3 Tor and is suitable for general applications; the ’LC’ version (contains corrosive resistance Platinum/Iridium filaments) can measure pressure down to 10-4 Torr and is also suitable for use in corrosive applications. These Edwards APG200-XM Active Pirani vacuum gauges with standard Tungsten/Rhenium filaments and NW16 vacuum flange. The APG200 can be mounted in any orientation however the gauge tubes are individually factory calibrated in nitrogen whilst vertical. For correct pressure indication in your chosen gauge orientation, the gauge should be recalibrated at atmospheric pressure. Edwards recommends mounting the gauge tube vertical in order to minimize the build up of process particulates and condensable vapors within the gauge. he APG200 is calibrated for use in nitrogen, and will read correctly with dry air, oxygen and carbon monoxide. For any other gas type a conversion is required in order to obtain the correct pressure reading, common gases: nitrogen, argon, carbon dioxide, helium, krypton and neon. Features Include: Easy Access to signal cable with compact enclosure Sensor bakable to 150°C (300°F) and sensor is user replaceable Adjustable set point for simple process control and interlocking Remote calibration possible Pressure range 10-3 TorrBackground On Pirani and Convection Enhanced Pirani GaugesPirani vacuum gauges can be classified as a thermal conductivity gauge being very similar to the thermocouple gauge where the resistance of the heated wire is measured to determine vacuum pressure. A Pirani gauge is designed to measure the resistance imbalance where the heated filament forms one of the arms of a Wheatstone bridge circuit. As the vacuum pressure increases, gas molecules transport heat away from the filament, and the resistance of the pressure sensor will move to a lower value which unbalances the circuit. The vacuum pressure is therefore calculated from the pressure induced imbalance in the Wheatstone bridge circuit. Just as with the thermocouple gauges, thermal conductivity by molecular collisions increases linearly with pressure over the 0.001 to 1 Torr pressure range. However, the heat removal becomes non-linear as the pressure is further increased into the viscous flow regime, where gas-gas collision can reorient molecules back towards the heated wire. Molecules have to collide many times before they reach the outer body of the sensor (the thermal sink). The convection-enhanced Pirani gauges take advantage of the convention current inside the sensor to extend its pressure measurement range all the way to atmospheric pressure. The Pirani gauge is an indirect pressure measurement sensors where measured readings are gas-type dependent. Some caution should be advised from the facts that heavier gases have poor heat transfer rates and that the standard convention-enhanced Pirani gauges are calibrated for N2 (basically the same calibration as Air). This could lead to dangerous overpressure conditions when back filling a vacuum systems with a heavier gas like argon. The danger arises if the vacuum system operator does not correct the gauge display reading for the correct gas-type, for example, a standard gauge calibrated for N2, displays 24 Torr when the chamber is at 760 Torr of argon. The operator would be fooled into thinking that the chamber was still under vacuum and continue to increase the system to a critical over-pressured state. Another source of error can be produced if the convection-enhanced Pirani gauge is not mounted correctly, most commercial sensors require that they are mounted parallel to the ground. This keeps the convention current inside the sensor flowing in the designed direction (errors of 20% or more can easily be introduced if the convention-enhanced Pirani sensor is not mount horizontally). Rapid evacuation of these convection-enhanced Pirani sensors will produce significant measurement error for a short period of several seconds. As the rapidly pumped gases expand, the removal of heat from the pressure sensor filament is not a normal convection current but is instead driven by forced convection. While the vacuum pressure is dropping rapidly the gases expand and cool, this provides a secondary pathway for removing heat from the hot sensor wire. The convection-enhanced Pirani gauge can falsely display high pressures up to 1000 Torr during system evacuation. Once the flow of gases is stopped the pressure reading will again stabilize to a realistic measured value. For these reasons, convection-enhanced Pirani gauges are not well suited for measuring pressure changes under dynamic pumping conditions. Overall, the convection-enhanced Pirani is a popular cost effective rough vacuum pressure gauge which can measures from Atmosphere to 1x10-4 Torr with those measurements below 1 Torr being most accurate.

Edwards APG200-MP Active Pirani Vacuum Gauge, Corrosion Resistant, No set Point, NW16, KF16, RJ45, Atmosphere down to 3.75x10-4 Torr, Analog output 0-10V. Edwards Part Number: D1G3011150 (Replaces APG-MP, PN: D02185000). Edwards APG200-MP Active Pirani Vacuum Gauge with a NW16, KF16 vacuum flange, is compact for easy installation, has a linear output. The new Edwards gauges are compatible with all Edwards TIC, ADC, TAG instrument controllers and other active gauge controllers and displays. They are also CSA, C/US approved as well as fully RoHS compliant due to their lead-free construction. They measure pressure from atmosphere down to 3.75x10-4 Torr. The signal cables and TIC vacuum gauge controllers are sold separately. The instruction manual for these Edwards APG200-MP series gauges is available in PDF format below. These gauges contain a Platinum / Rhodium (90/10) filament, stainless steel 316L and 304L, glass, Ni and NiFe. These Edwards APG200-MP Active Pirani vacuum gauges have a KF16, NW16 vacuum flange are new with Edwards part number D1G3011150. The APG200 is available in three versions: M, LC, and MP series. The M series contains standard Tungsten/Rhenium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The LC version contains corrosive resistance Platinum/Iridium filaments, it can measure pressure from atmosphere down to 7.5x10-5 Torr, and is also suitable for use in corrosive applications. The MP series contains Platinum/Rhodium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The instruction manual for these Edwards APG200 series gauges is available in PDF format below. The APG200 can be mounted in any orientation however the gauge tubes are individually factory calibrated in nitrogen while vertical. For correct pressure indication in your chosen gauge orientation, the gauge should be recalibrated at atmospheric pressure. Edwards recommends mounting the gauge tube vertical in order to minimize the build up of process particulates and condensable vapors within the gauge. The APG200 is calibrated for use in nitrogen, and will read correctly with dry air, oxygen and carbon monoxide. For any other gas type a conversion is required in order to obtain the correct pressure reading, common gases: nitrogen, argon, carbon dioxide, helium, krypton and neon. Features Include: Easy Access to signal cable with compact enclosure Adjustable set point for simple process control and interlocking Set Points Remote calibration possible Pressure range 10-4 Torr Background On Pirani and Convection Enhanced Pirani GaugesPirani vacuum gauges can be classified as a thermal conductivity gauge being very similar to the thermocouple gauge where the resistance of the heated wire is measured to determine vacuum pressure. A Pirani gauge is designed to measure the resistance imbalance where the heated filament forms one of the arms of a Wheatstone bridge circuit. As the vacuum pressure increases, gas molecules transport heat away from the filament, and the resistance of the pressure sensor will move to a lower value which unbalances the circuit. The vacuum pressure is therefore calculated from the pressure induced imbalance in the Wheatstone bridge circuit. Just as with the thermocouple gauges, thermal conductivity by molecular collisions increases linearly with pressure over the 0.001 to 1 Torr pressure range. However, the heat removal becomes non-linear as the pressure is further increased into the viscous flow regime, where gas-gas collision can reorient molecules back towards the heated wire. Molecules have to collide many times before they reach the outer body of the sensor (the thermal sink). The convection-enhanced Pirani gauges take advantage of the convention current inside the sensor to extend its pressure measurement range all the way to atmospheric pressure. The Pirani gauge is an indirect pressure measurement sensors where measured readings are gas-type dependent. Some caution should be advised from the facts that heavier gases have poor heat transfer rates and that the standard convention-enhanced Pirani gauges are calibrated for N2 (basically the same calibration as Air). This could lead to dangerous overpressure conditions when back filling a vacuum systems with a heavier gas like argon. The danger arises if the vacuum system operator does not correct the gauge display reading for the correct gas-type, for example, a standard gauge calibrated for N2, displays 24 Torr when the chamber is at 760 Torr of argon. The operator would be fooled into thinking that the chamber was still under vacuum and continue to increase the system to a critical over-pressured state. Another source of error can be produced if the convection-enhanced Pirani gauge is not mounted correctly, most commercial sensors require that they are mounted parallel to the ground. This keeps the convention current inside the sensor flowing in the designed direction (errors of 20% or more can easily be introduced if the convention-enhanced Pirani sensor is not mount horizontally). Rapid evacuation of these convection-enhanced Pirani sensors will produce significant measurement error for a short period of several seconds. As the rapidly pumped gases expand, the removal of heat from the pressure sensor filament is not a normal convection current but is instead driven by forced convection. While the vacuum pressure is dropping rapidly the gases expand and cool, this provides a secondary pathway for removing heat from the hot sensor wire. The convection-enhanced Pirani gauge can falsely display high pressures up to 1000 Torr during system evacuation. Once the flow of gases is stopped the pressure reading will again stabilize to a realistic measured value. For these reasons, convection-enhanced Pirani gauges are not well suited for measuring pressure changes under dynamic pumping conditions. Overall, the convection-enhanced Pirani is a popular cost effective rough vacuum pressure gauge which can measures from Atmosphere to 1x10-4 Torr with those measurements below 1 Torr being most accurate.

Edwards Active Pirani Vacuum Gauge APG200-MP-NW25 Stainless Steel, KF25, Flange. 10-3 Torr. Edwards APG200-MP Part Number D1G3021150, (Replaces APG100-MP Part Number D02182000). Edwards Active Pirani Vacuum Gauge APG-MP Active Pirani Vacuum Gauge contains a NW25, KF25 vacuum flange, is compact for easy installation, has a linear output. The new Edwards gauges are compatible with all Edwards TIC, ADC, TAG instrument controllers and other active gauge controllers and displays. They are also CSA, C/US approved as well as fully RoHS compliant due to their lead-free construction. They measure pressure from 1000 down to 10-3 Torr. The signal cables and TIC vacuum gauge controllers are sold separately. The instruction manual for these Edwards APG200-MP series gauges is available in PDF format below. This gague contains a Platinum / rhodium (90/10) filament and can measure pressure down to 10-3 Torr and is stainless steel. These Edwards APG200-MP Active Pirani vacuum gauges has a KF25 NW25 vacuum flange are new with Edwards part number D1G3021150. If you connected the APG to a Edwards AGC controller or AGD display, use the set-point adjustment procedure detailed in the instruction manual supplied with the unit. If you connected the APG to your own control equipment, use the procedure on page 22 of the manual.pdf below. The APG200-MP can be mounted in any orientation however the gauge tubes are individually factory calibrated in nitrogen whilst vertical. For correct pressure indication in your chosen gauge orientation, the gauge should be recalibrated at atmospheric pressure. Edwards recommends mounting the gauge tube vertical in order to minimize the build up of process particulates and condensable vapors within the gauge. The APG200 MP is calibrated for use in nitrogen, and will read correctly with dry air, oxygen and carbon monoxide. For any other gas type a conversion is required in order to obtain the correct pressure reading, common gases: nitrogen, argon, carbon dioxide, helium, krypton and neon. Features Include: Easy Access to signal cable with compact enclosure Adjustable set point for simple process control and interlocking Set Points Remote calibration possible Pressure range 10-3 Torr Background On Pirani and Convection Enhanced Pirani GaugesPirani vacuum gauges can be classified as a thermal conductivity gauge being very similar to the thermocouple gauge where the resistance of the heated wire is measured to determine vacuum pressure. A Pirani gauge is designed to measure the resistance imbalance where the heated filament forms one of the arms of a Wheatstone bridge circuit. As the vacuum pressure increases, gas molecules transport heat away from the filament, and the resistance of the pressure sensor will move to a lower value which unbalances the circuit. The vacuum pressure is therefore calculated from the pressure induced imbalance in the Wheatstone bridge circuit. Just as with the thermocouple gauges, thermal conductivity by molecular collisions increases linearly with pressure over the 0.001 to 1 Torr pressure range. However, the heat removal becomes non-linear as the pressure is further increased into the viscous flow regime, where gas-gas collision can reorient molecules back towards the heated wire. Molecules have to collide many times before they reach the outer body of the sensor (the thermal sink). The convection-enhanced Pirani gauges take advantage of the convention current inside the sensor to extend its pressure measurement range all the way to atmospheric pressure. The Pirani gauge is an indirect pressure measurement sensors where measured readings are gas-type dependent. Some caution should be advised from the facts that heavier gases have poor heat transfer rates and that the standard convention-enhanced Pirani gauges are calibrated for N2 (basically the same calibration as Air). This could lead to dangerous overpressure conditions when back filling a vacuum systems with a heavier gas like argon. The danger arises if the vacuum system operator does not correct the gauge display reading for the correct gas-type, for example, a standard gauge calibrated for N2, displays 24 Torr when the chamber is at 760 Torr of argon. The operator would be fooled into thinking that the chamber was still under vacuum and continue to increase the system to a critical over-pressured state. Another source of error can be produced if the convection-enhanced Pirani gauge is not mounted correctly, most commercial sensors require that they are mounted parallel to the ground. This keeps the convention current inside the sensor flowing in the designed direction (errors of 20% or more can easily be introduced if the convention-enhanced Pirani sensor is not mount horizontally). Rapid evacuation of these convection-enhanced Pirani sensors will produce significant measurement error for a short period of several seconds. As the rapidly pumped gases expand, the removal of heat from the pressure sensor filament is not a normal convection current but is instead driven by forced convection. While the vacuum pressure is dropping rapidly the gases expand and cool, this provides a secondary pathway for removing heat from the hot sensor wire. The convection-enhanced Pirani gauge can falsely display high pressures up to 1000 Torr during system evacuation. Once the flow of gases is stopped the pressure reading will again stabilize to a realistic measured value. For these reasons, convection-enhanced Pirani gauges are not well suited for measuring pressure changes under dynamic pumping conditions. Overall, the convection-enhanced Pirani is a popular cost effective rough vacuum pressure gauge which can measures from Atmosphere to 1x10-4 Torr with those measurements below 1 Torr being most accurate.

Edwards APG200-XLC Active Pirani Vacuum Gauge, Corrosion Resistant, No set Point, NW16, KF16 Flange, Atmosphere Down to 7.5x10-5 Torr, Analog output 0-10V. Edwards Part Number D1G2011100, (Replaces APG100-XLC D02603000). The Edwards APG200-XLC Active Pirani Vacuum Gauge (Corrosion Resistant Platinum/Iridium Filament) contains a NW16, KF16 flange, is compact for easy installation, has a linear output, and a user replaceable sensor tube. The new Edwards gauges are compatible with all Edwards TIC, ADC, TAG instrument controllers and other active gauge controllers and displays. They are also CSA, C/US approved as well as fully RoHS compliant due to their lead-free construction. They measure pressure from atmosphere down to 7.5x10-5 Torr. Signal cable and controller not supplied. The signal cable and vacuum gauge controller are sold separately. These Edwards APG200-XLC Active Pirani vacuum gauges with corrosive resistance Platinum/Iridium filament and NW16 vacuum flange are new with Edwards part number D1G2011100. The APG200 is available in three versions: M, LC, and MP series. The M series contains standard Tungsten/Rhenium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The LC version contains corrosive resistance Platinum/Iridium filaments, it can measure pressure from atmosphere down to 7.5x10-5 Torr, and is also suitable for use in corrosive applications. The MP series contains Platinum/Rhodium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The instruction manual for these Edwards APG200 series gauges is available in PDF format below. The APG200 can be mounted in any orientation however the gauge tubes are individually factory calibrated in nitrogen while vertical. For correct pressure indication in your chosen gauge orientation, the gauge should be recalibrated at atmospheric pressure. Edwards recommends mounting the gauge tube vertical in order to minimize the build up of process particulates and condensable vapors within the gauge. The APG200 is calibrated for use in nitrogen, and will read correctly with dry air, oxygen and carbon monoxide. For any other gas type a conversion is required in order to obtain the correct pressure reading, common gases: nitrogen, argon, carbon dioxide, helium, krypton and neon. Features Include: Easy Access to signal cable with compact enclosure Sensor bakable to 150°C (300°F) and sensor is user replaceable Adjustable set point for simple process control and interlocking Remote calibration possible Corrosion Resistant Pressure range 10-5 TorrBackground On Pirani and Convection Enhanced Pirani GaugesPirani vacuum gauges can be classified as a thermal conductivity gauge being very similar to the thermocouple gauge where the resistance of the heated wire is measured to determine vacuum pressure. A Pirani gauge is designed to measure the resistance imbalance where the heated filament forms one of the arms of a Wheatstone bridge circuit. As the vacuum pressure increases, gas molecules transport heat away from the filament, and the resistance of the pressure sensor will move to a lower value which unbalances the circuit. The vacuum pressure is therefore calculated from the pressure induced imbalance in the Wheatstone bridge circuit. Just as with the thermocouple gauges, thermal conductivity by molecular collisions increases linearly with pressure over the 0.001 to 1 Torr pressure range. However, the heat removal becomes non-linear as the pressure is further increased into the viscous flow regime, where gas-gas collision can reorient molecules back towards the heated wire. Molecules have to collide many times before they reach the outer body of the sensor (the thermal sink). The convection-enhanced Pirani gauges take advantage of the convention current inside the sensor to extend its pressure measurement range all the way to atmospheric pressure. The Pirani gauge is an indirect pressure measurement sensors where measured readings are gas-type dependent. Some caution should be advised from the facts that heavier gases have poor heat transfer rates and that the standard convention-enhanced Pirani gauges are calibrated for N2 (basically the same calibration as Air). This could lead to dangerous overpressure conditions when back filling a vacuum systems with a heavier gas like argon. The danger arises if the vacuum system operator does not correct the gauge display reading for the correct gas-type, for example, a standard gauge calibrated for N2, displays 24 Torr when the chamber is at 760 Torr of argon. The operator would be fooled into thinking that the chamber was still under vacuum and continue to increase the system to a critical over-pressured state. Another source of error can be produced if the convection-enhanced Pirani gauge is not mounted correctly, most commercial sensors require that they are mounted parallel to the ground. This keeps the convention current inside the sensor flowing in the designed direction (errors of 20% or more can easily be introduced if the convention-enhanced Pirani sensor is not mount horizontally). Rapid evacuation of these convection-enhanced Pirani sensors will produce significant measurement error for a short period of several seconds. As the rapidly pumped gases expand, the removal of heat from the pressure sensor filament is not a normal convection current but is instead driven by forced convection. While the vacuum pressure is dropping rapidly the gases expand and cool, this provides a secondary pathway for removing heat from the hot sensor wire. The convection-enhanced Pirani gauge can falsely display high pressures up to 1000 Torr during system evacuation. Once the flow of gases is stopped the pressure reading will again stabilize to a realistic measured value. For these reasons, convection-enhanced Pirani gauges are not well suited for measuring pressure changes under dynamic pumping conditions. Overall, the convection-enhanced Pirani is a popular cost effective rough vacuum pressure gauge which can measures from Atmosphere to 1x10-4 Torr with those measurements below 1 Torr being most accurate.

Edwards APG 200-XLC Active Pirani Vacuum Gauge NW25, KF25 Flange, No Setpoint, Corrosion Resistant, Atmosphere Down to 7.5x10-5 Torr, Analog output 0-10V. Edwards Part Number D1G2021100, (Replaces APG100-XLC Part Number D02604000). The Edwards APG 200-XLC Active Pirani Vacuum Gauge(Corrosion Resistant Platinum/Iridium Filament) contains a NW25, KF25 vacuum flange, is compact for easy installation, has a linear output, and a user replaceable tube sensor. The Edwards gauges are compatible with all Edwards TIC, ADC, TAG instrument controllers and other active gauge controllers and displays. They are also CSA, C/US approved as well as fully RoHS compliant due to their lead-free construction. They measure from atmosphere down to 7.5x10-5. The signal cables and TIC vacuum gauge controllers are sold separately. These Edwards APG200-XLC Active Pirani vacuum gauges with corrosive resistance Platinum/Iridium filament and NW25 vacuum flange are new with Edwards part number D1G2021100. The APG200 is available in three versions: M, LC, and MP series. The M series contains standard Tungsten/Rhenium filaments, it can measure pressure from atmosphere down to 7.5x10-5 Torr, and is suitable for general applications. The LC version contains corrosive resistance Platinum/Iridium filaments, it can measure pressure from atmosphere down to 7.5x10-5 Torr, and is also suitable for use in corrosive applications. The MP series contains Platinum/Rhodium filaments, it can measure pressure from atmosphere down to 7.5x10-5 Torr, and is suitable for general applications. The instruction manual for these Edwards APG200 series gauges is available in PDF format below. The APG200 can be mounted in any orientation however the gauge tubes are individually factory calibrated in nitrogen while vertical. For correct pressure indication in your chosen gauge orientation, the gauge should be recalibrated at atmospheric pressure. Edwards recommends mounting the gauge tube vertical in order to minimize the build up of process particulates and condensable vapors within the gauge. The APG200 is calibrated for use in nitrogen, and will read correctly with dry air, oxygen and carbon monoxide. For any other gas type a conversion is required in order to obtain the correct pressure reading, common gases: nitrogen, argon, carbon dioxide, helium, krypton and neon. Features Include: Easy Access to signal cable with compact enclosure Sensor bakable to 150°C (300°F) and sensor is user replaceable Adjustable set point for simple process control and interlocking Remote calibration possible Corrosion Resistant Pressure range 10-5 Torr Background On Pirani and Convection Enhanced Pirani GaugesPirani vacuum gauges can be classified as a thermal conductivity gauge being very similar to the thermocouple gauge where the resistance of the heated wire is measured to determine vacuum pressure. A Pirani gauge is designed to measure the resistance imbalance where the heated filament forms one of the arms of a Wheatstone bridge circuit. As the vacuum pressure increases, gas molecules transport heat away from the filament, and the resistance of the pressure sensor will move to a lower value which unbalances the circuit. The vacuum pressure is therefore calculated from the pressure induced imbalance in the Wheatstone bridge circuit. Just as with the thermocouple gauges, thermal conductivity by molecular collisions increases linearly with pressure over the 0.001 to 1 Torr pressure range. However, the heat removal becomes non-linear as the pressure is further increased into the viscous flow regime, where gas-gas collision can reorient molecules back towards the heated wire. Molecules have to collide many times before they reach the outer body of the sensor (the thermal sink). The convection-enhanced Pirani gauges take advantage of the convention current inside the sensor to extend its pressure measurement range all the way to atmospheric pressure. The Pirani gauge is an indirect pressure measurement sensors where measured readings are gas-type dependent. Some caution should be advised from the facts that heavier gases have poor heat transfer rates and that the standard convention-enhanced Pirani gauges are calibrated for N2 (basically the same calibration as Air). This could lead to dangerous overpressure conditions when back filling a vacuum systems with a heavier gas like argon. The danger arises if the vacuum system operator does not correct the gauge display reading for the correct gas-type, for example, a standard gauge calibrated for N2, displays 24 Torr when the chamber is at 760 Torr of argon. The operator would be fooled into thinking that the chamber was still under vacuum and continue to increase the system to a critical over-pressured state. Another source of error can be produced if the convection-enhanced Pirani gauge is not mounted correctly, most commercial sensors require that they are mounted parallel to the ground. This keeps the convention current inside the sensor flowing in the designed direction (errors of 20% or more can easily be introduced if the convention-enhanced Pirani sensor is not mount horizontally). Rapid evacuation of these convection-enhanced Pirani sensors will produce significant measurement error for a short period of several seconds. As the rapidly pumped gases expand, the removal of heat from the pressure sensor filament is not a normal convection current but is instead driven by forced convection. While the vacuum pressure is dropping rapidly the gases expand and cool, this provides a secondary pathway for removing heat from the hot sensor wire. The convection-enhanced Pirani gauge can falsely display high pressures up to 1000 Torr during system evacuation. Once the flow of gases is stopped the pressure reading will again stabilize to a realistic measured value. For these reasons, convection-enhanced Pirani gauges are not well suited for measuring pressure changes under dynamic pumping conditions. Overall, the convection-enhanced Pirani is a popular cost effective rough vacuum pressure gauge which can measures from Atmosphere to 1x10-4 Torr with those measurements below 1 Torr being most accurate.

Edwards APG200-M Active Pirani Vacuum Gauge NW25, KF25, S Matched, Non-Linear Output, Atmosphere Down to 3.75x10-4. Edwards Part Number D1G1021150, (Replaces APG100-M PN: D02606000). The Edwards APG200-M Active Pirani Vacuum Gauge contains a NW25, KF25 vacuum flange, is compact for easy installation, has a NON-LINEAR OUTPUT, and a user replaceable tube sensor. The new Edwards gauges are compatible with all Edwards TIC, ADC, TAG instrument controllers and other active gauge controllers and displays. They are also CSA, C/US approved as well as fully RoHS compliant due to their lead-free construction. They measure pressure from atmosphere down to 3.75x10-4. The signal cables and TIC vacuum gauge controllers are sold separately. These Edwards APG200-M Active Pirani vacuum gauges with standard Tungsten/Rhenium filaments and NW25 vacuum flange with Edwards Part Number D1G1021150. The APG200 is available in three versions: M, LC, and MP series. The M series contains standard Tungsten/Rhenium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The LC version contains corrosive resistance Platinum/Iridium filaments, it can measure pressure from atmosphere down to 7.5x10-5 Torr, and is also suitable for use in corrosive applications. The MP series contains Platinum/Rhodium filaments, it can measure pressure from atmosphere down to 3.75x10-4 Torr, and is suitable for general applications. The instruction manual for these Edwards APG200 series gauges is available in PDF format below. The APG200 can be mounted in any orientation however the gauge tubes are individually factory calibrated in nitrogen while vertical. For correct pressure indication in your chosen gauge orientation, the gauge should be recalibrated at atmospheric pressure. Edwards recommends mounting the gauge tube vertical in order to minimize the build up of process particulates and condensable vapors within the gauge. The APG200 is calibrated for use in nitrogen, and will read correctly with dry air, oxygen and carbon monoxide. For any other gas type a conversion is required in order to obtain the correct pressure reading, common gases: nitrogen, argon, carbon dioxide, helium, krypton and neon. Features Include: Easy Access to signal cable with compact enclosure Sensor bakable to 150°C (300°F) and sensor is user replaceable Adjustable set point for simple process control and interlocking Remote calibration possible Pressure range 10-4 TorrBackground On Pirani and Convection Enhanced Pirani GaugesPirani vacuum gauges can be classified as a thermal conductivity gauge being very similar to the thermocouple gauge where the resistance of the heated wire is measured to determine vacuum pressure. A Pirani gauge is designed to measure the resistance imbalance where the heated filament forms one of the arms of a Wheatstone bridge circuit. As the vacuum pressure increases, gas molecules transport heat away from the filament, and the resistance of the pressure sensor will move to a lower value which unbalances the circuit. The vacuum pressure is therefore calculated from the pressure induced imbalance in the Wheatstone bridge circuit. Just as with the thermocouple gauges, thermal conductivity by molecular collisions increases linearly with pressure over the 0.001 to 1 Torr pressure range. However, the heat removal becomes non-linear as the pressure is further increased into the viscous flow regime, where gas-gas collision can reorient molecules back towards the heated wire. Molecules have to collide many times before they reach the outer body of the sensor (the thermal sink). The convection-enhanced Pirani gauges take advantage of the convention current inside the sensor to extend its pressure measurement range all the way to atmospheric pressure. The Pirani gauge is an indirect pressure measurement sensors where measured readings are gas-type dependent. Some caution should be advised from the facts that heavier gases have poor heat transfer rates and that the standard convention-enhanced Pirani gauges are calibrated for N2 (basically the same calibration as Air). This could lead to dangerous overpressure conditions when back filling a vacuum systems with a heavier gas like argon. The danger arises if the vacuum system operator does not correct the gauge display reading for the correct gas-type, for example, a standard gauge calibrated for N2, displays 24 Torr when the chamber is at 760 Torr of argon. The operator would be fooled into thinking that the chamber was still under vacuum and continue to increase the system to a critical over-pressured state. Another source of error can be produced if the convection-enhanced Pirani gauge is not mounted correctly, most commercial sensors require that they are mounted parallel to the ground. This keeps the convention current inside the sensor flowing in the designed direction (errors of 20% or more can easily be introduced if the convention-enhanced Pirani sensor is not mount horizontally). Rapid evacuation of these convection-enhanced Pirani sensors will produce significant measurement error for a short period of several seconds. As the rapidly pumped gases expand, the removal of heat from the pressure sensor filament is not a normal convection current but is instead driven by forced convection. While the vacuum pressure is dropping rapidly the gases expand and cool, this provides a secondary pathway for removing heat from the hot sensor wire. The convection-enhanced Pirani gauge can falsely display high pressures up to 1000 Torr during system evacuation. Once the flow of gases is stopped the pressure reading will again stabilize to a realistic measured value. For these reasons, convection-enhanced Pirani gauges are not well suited for measuring pressure changes under dynamic pumping conditions. Overall, the convection-enhanced Pirani is a popular cost effective rough vacuum pressure gauge which can measures from Atmosphere to 1x10-4 Torr with those measurements below 1 Torr being most accurate.