The high-performance measurement transmitter testo 6621 is a reliable partner for applications in building air conditioning. Accuracy, long-term stability and reliability – our measurement transmitter meets the high demands of building automation, helping you to reduce costs.

The testo 6601 temperature and humidity probe is designed for monitoring critical indoor climates.

The testo 6602 temperature and humidity probe is designed for measurements in air conditioning ducts.

The testo 6603 temperature and humidity probe is designed for measurements in air conditioning ducts, is equipped with a high-precision, long-term stable humidity sensor from Testo and delivers precise measurement results.

The testo 6604 temperature and humidity probe is designed for measurements in processes that are difficult to access.

The testo 6605 temperature and humidity probe is equipped with a high-precision, long-term stable humidity sensor from Testo and delivers precise measurement results.

The testo 6611 temperature and humidity probe is designed for monitoring critical indoor climates.

The testo 6612 temperature and humidity probe is designed for measurements in air conditioning ducts.

The testo 6613 temperature and humidity probe is designed for measurements in processes that are difficult to access.

The testo 6614 temperature and humidity probe is designed for measurements in processes that are difficult to access. With its integrated sensor heating, the humidity sensor is optimally protected against condensation and corrosion – so you can enjoy high-precision measurement results, even with high process humidity, and benefit from its long service life.

The testo 6615 temperature and humidity probe is designed for measurements in trace humidity applications. The automatic self-adjustment procedure corrects the measurement uncertainties that traditionally occur when measuring humidity in the lowest humidity ranges - so you benefit from extremely accurate measurement results.

The testo 6617 temperature and humidity probe is designed for measurements in environments with aggressive media. With the built-in self-monitoring function, you can prevent faulty measurements or measurement interruptions – because it detects signs of corrosion at an early stage, thus the probe can be replaced in good time.

This certificate documents the ISO calibration of your data logger or transmitter. Calibration is carried out at the measuring points 11.3 %RH, 50 %RH, 75.3 %RH at a temperature of +25 °C.

ISO calibration certificate for humidity - with three measuring points

ISO calibration certificate for humidity - with three measuring points