testo 6621 – wall moisture transmitter with external sensor
Wall-mounted humidity transmitter with external sensor and display
- External sensor - benefit of faster response time and easier calibration
- Measuring range of moisture: 0...100%.
- Measuring range temperature: 0... +60°C
testo 6621 - wall-mounted moisture transmitter with display and external sensor
The testo 6621 is a compact moisture transmitter series with a stylish design and a wide range of options. The high-accuracy and long-term stable moisture sensor is the heart of Testo's 6621 transmitter series, which can be adapted to most applications due to its wide range of options. As an option, the user-friendly software P2A is available, which allows the adjustment of the transmitters, parameterization of units and scale, provides history of all events, etc.
Available in designs:
- For wall mounting with internal or external sensor and for duct mounting
- With or without display
- Optional output signals 4-20 mA, 0-1 V, 0-5 V, 0-10 V
- Optional types of filters - Teflon, metal sinter, mesh, etc.
Contact us for prices and more information
| Enclosure Material | ABS |
| Measure | 81x81x26mm |
| Protection class | IP65 |
| Operating temperature | Electronics (instrument housing) -20...+70°C Display: ±0...+50°C |
| Screw connection | 1xM16x1.5 |
| Moisture sensor | Testo moisture sensor |
| Temperature sensor | NTC sensor |
| Measurement range | Humidity: 0...100 %RH Temperature: ±0...60°C |
| Adjustment points | 11.3%RH, 75.3%RH and that the analog output can also be adjusted" |
| Accuracy : | |
| Moisture | ±2.5 %RH (0...90%RH) ±4 %RH (90...100%RH) |
| temp | 0,5°C |
| Analog output: | 4...20 mA (2-wire technology) two separate outputs 0...1V (4-wire technology) two separate outputs 0...5V (4-wire technology) two separate outputs 0...10V (4-wire technology) two separate outputs |
| Power supply | With analog output: 24VDC ±10% With volt output: 20...30VDC |
| EMC | In accordance with Directive 89/336 EEC |
| Sensor insertion length: | 220mm |





