What are affordable alternatives to benchtop DAQ systems for precision measurements?

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For environmental measurements (temperature, humidity, pressure, CO2), Dracal USB instruments are a much simpler and more affordable alternative. A benchtop DAQ system needs the acquisition unit, separate sensors, signal conditioning and often a software licence. A Dracal instrument combines the sensor and the acquisition in one calibrated device, and comes with free software and data integration tools. Precision is not sacrificed: PTH450: ±0.1 °C, ±1.5 %RH and ±0.15 kPa in one probe RTD300 with a Pt100 probe: the accuracy of the system is the sum of the transmitter (±0.018 °C from 0 °C to 50 °C) and the probe. At 0 °C, that gives about ±0.12 °C with our 1/3 DIN RTD-PT100-SIL probe (±0.10 °C), or about ±0.32 °C with a standard class B Pt100 probe (±0.30 °C according to IEC 60751). Here is why the probe counts. TMC200: thermocouple types K, J, T, N and E, from -200 °C up to 1372 °C (type K), with a 0.01 °C resolution and built-in cold junction compensation Our article Do you really need a $2,000 environmental transmitter? compares the costs in detail, and this cost benefit analysis looks at the whole picture. A benchtop system remains the right choice for fast signals, voltages or very high channel counts on the same clock.