Historically the 2A thermocouple sensor had a measurement range up to only 20 Torr and the 4A convection sensor was used to measure pressures up to 1000 Torr. Software and drive signal enhancements incorporated into the MX2A active thermocouple gauge now allow the 2A thermocouple sensor to measure pressures up to 1000 Torr. This has raised questions about the differences between the MX2A thermocouple active gauge and the MX4A active convection gauge as almost all of their specifications are now identical. This document outlines the differences between the two active gauges.
Differences Between the MX2A and MX4A
|Response Time||<2 seconds||<1 second|
|Accuracy||±30% (10 to 100 Torr)||±10% (10 to 100 Torr)|
|Materials Exposed to Vacuum||NiMnSi Alloy, CuNiMn Alloy||NiCr Alloy, CuNi Alloy|
All other specifications for the MX2A and MX4A are equivalent.