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APAS T1 Substrate Moisture Sensor with New Cable Length Options

Updated: Mar 28

We recently updated the APAS T1 design (Rev. 2). The APAS T1 is now available with three standard cable lengths of:

1) 1.8 m (6 ft) (APAS T1-1.8C)

2) 3.0 m (9.8 ft) (APAS T1-3.3C)

3) 4.5 m (14.8 ft) (APAS T1-4.5C)

Cable length is automatically detected when a sensor is connected to any DurUntash readout device. This helps with applying appropriate calibration coefficients to adjust sensor readings.

In case this is the first time you hear about the APAS T1, here’s what makes this sensor special:

1) The APAS T1 is designed by scientists who were tired of trying so many commercial sensors that weren’t working!

2) The first model of this sensor was designed over 15 years ago when we were operating under the name “Irrigation & Drainage Research Group” (IDRG SMS-T1).

3) The sensor is specifically designed and optimized for soilless media (e.g. #rockwool, #coco coir).

4) It has an impressive volume of influence of over 800 ml.

5) It measures temperature using the a digital sensor and compensates sensor readings for temp effect.

6) The electronics are protected by an electronic-grade #epoxy filling.

7) The sensor is capacitive and its electrodes are inside a 4-layer #PCB. So, the sensor is fully waterproof and will last a very long time.

8) Each sensor has a unique 64-bit digital ID and power consumption of ~15 mA (@3.3 V) making it ideal for IoT applications.

9) We provide a variety of professional USB and wireless (Bluetooth, WiFi, LoRa) readout devices that you can use to take sensor readings.

10) The APAS T1 sensor is fully compatible with #Arduino boards, and you can find related Arduino sketch on our website. It can also be interfaced with the Raspberry Pi using our sensor adapters.

11) By adding ferrite bead and #ferrite core to both the sensor circuitry and cable, cable noise is eliminated from measurements.



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