GroPoint™ Bluetooth SDI-12 Data Logger
Log data and retrieve it wirelessly on your smartphone.
The GroPoint Bluetooth SDI-12 Data Logger is a wireless access point to retrieve data from ANY SDI-12 sensor.
Natively connects up to 10 SDI-12 sensors (via multiple 4-Port SDI-12 Expansion Bars).
Customize your data collection by choosing logging intervals and configurations that fit your needs.
Powered by internal batteries:
Default option: 2x AA Lithium Metal (Included)
Optional: 1x High Performance C-Cell (Purchase Seperately)
Retrieve sensor data with our free GP Reader app available for Android devices (iOS coming soon).
AA Lithium Battery
High Performance C-Cell Battery
Bluetooth SDI-12 Data Logger
The GP-BTDL Bluetooth SDI-12 Data Logger is a wireless data logger that lets you retrieve data through your Android device. It is left on site to reliably collect data from your GroPoint soil sensors or other SDI-12 sensors, so you can access the data when convenient.
The logger collects and stores up to 4 MB of environmental data such as soil moisture, temperature, EC, and more. Data is stored in non-volatile memory and is retained even if the battery fails, with capacity for up to 200,000 measurements.
The free GP Reader app for Android devices is used to check current conditions, download data, and set the sampling interval from one minute to 12 hours. With the app open on your smartphone, simply press the button on the GP-BTDL to wake it up and automatically establish a wireless connection, then tap Download to retrieve all logged data.
The GP-BTDL connects to up to 10 SDI-12 sensors with the 4-Port SDI-12 Expansion Bar and supports cable lengths up to 200 ft as per SDI-12 specifications. Sensors must terminate in an M12 connector, and the data logger works with most V1.3 SDI-12 sensors.
Features
- Retrieve sensor data wirelessly to your smartphone with a quick visit to the app.
- Stay connected up to 60 m (200 ft) away.
- Operates with a primary C-cell battery (3.6 V) or 2 × AA 1.5 V lithium
- Battery life up to several years depending on number of sensors and sample rate.
- Water resistant, IP65 rated enclosure.
- Data is retained even with no battery.
- Free GP Reader app available for Android devices.
- Works with most SDI-12 compliant third-party sensors
- Specifications
- FAQs
- Downloads
| Output | Choice of data format: .txt, .csv or .dat retrieved via Bluetooth |
| Sensor interface | SDI-12 |
| Sensor port connector | 1 × M12 (5 female pins) |
| Maximum number of sensors |
10 (via multiple 4-Port SDI-12 Expansion Bars) Depending on measurement interval and type of sensor, additional sensors may be configured. Up to 60 SDI-12 sensors may be configured depending on cable length and sensor power requirements. |
| Wireless protocol | Bluetooth 4.0 LE |
| Storage |
4 MB This is the equivalent of: > 200K GroPoint Lite soil moisture and soil temperature measurements > 80K soil moisture and soil temperature measurements from a GroPoint Profile 4-segment sensor |
| Measurement interval |
Configurable by user Range: 1 minute to 12 hours |
| Operating temperature range | -20°C to 65°C (-4°F to 150°F) |
| Storage temperature range | -20°C to 70°C (-4°F to 160°F) |
| Power |
3.0 V lithium coin cell powers the memory (included) 2 × AA alkaline batteries or 3.6 V 1 × C-cell Li-ion battery powers the sensors (ordered separately) |
| Battery life | Up to several years, depending on measurement interval and battery selection |
| Dimensions | 11.4 cm × 8.0 cm × 6.0 cm (4.49" × 3.15" × 2.36") |
| Weight | 216 g (7.62 oz) |
| Warranty | 1-year limited parts and labour |
| Environmental sealing |
Enclosure: IP65 Push button: IP67 Sensor connectors: IP66 / IP68 |
| Order number | Part 2992 |
Is over-the-air firmware updating supported on the GroPoint Bluetooth Datalogger?
GroPoint Bluetooth Dataloggers with firmware versions 3.3 and higher support FOTA updates. See the
GP-BTDL manual for instructions.
Is the Bluetooth Datalogger compatible with non-GroPoint sensors?
Yes. The GroPoint Bluetooth datalogger can be used with other third party SDI-12 sensors as long as they conform to SDI-12 protocol, can run from a switched 9 V power supply, the sensor power draw does not exceed 50 mA continuous and 100 mA peak, and a 2 second power on delay is a sufficient warm up time. Sensors that require continuous power can be used if external power is supplied to the sensor.
Is the GP Reader app available on Apple devices?
At the moment, the Bluetooth SDI-12 Data Logger software GP Reader is only available for Android devices.
Please let us know if you require iOS support so we can
prioritize this work based on demand.
Which Android versions does the GP Reader app support?
Android 8 and higher.
What communication protocol and electrical interface does the GroPoint Bluetooth Datalogger support?
The GroPoint Bluetooth Datalogger only supports SDI-12 communication and electrical interface.
How do I connect my sensor that does not have a connector to the Bluetooth Datalogger?
To connect a sensor that does not have a connector, you will need to purchase an M12 5-pin code A male
connector to attach to your sensor. The pin connections are:
Pin 1: Sensor power
Pin 2: None
Pin 3: None
Pin 4: SDI-12 I/O
Pin 5: GND
)
How many sensors can be connected to one Bluetooth Datalogger?
GroPoint Bluetooth Dataloggers follow the SDI-12 standard which supports up to 10 sensors on a single
SDI-12 bus. GroPoint BTDL kits come with either a 4-port or 2-port expansion bar to connect multiple
sensors to one BTDL.
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How can I change my sensor address using the Bluetooth Datalogger?
Only one sensor can be attached when changing the sensor address. In the GP Reader app, press Change
Address. The current sensor address is displayed and you can select a new one by dragging the blue dot
around the wheel. Once an address is chosen, press Set Address.
Does the Bluetooth Datalogger need to be kept in a watertight enclosure?
The Bluetooth SDI-12 Datalogger enclosure is IP76 rated, which means it can withstand immersion in water
up to one meter for 30 minutes under lab conditions. This is not considered an environmentally hardened
enclosure. While you do not need an additional watertight enclosure, it is a good idea to keep the
datalogger out of direct exposure to the elements. Covering it with a structure and raising it off the
ground are both good ideas.
Is it possible to send custom SDI-12 commands to sensors using the Bluetooth Datalogger?
GP Reader has a transparent mode for sending SDI-12 commands to a connected sensor. Press and hold
Measure to activate transparent command mode.
How can I change the logging interval on my Bluetooth Datalogger?
To change the logging interval, go to the configuration menu by pressing Config. Select the desired
measurement interval from the drop down list then press Update. The BTDL cannot be logging while you
change configuration settings so you must download any logged data, then stop and erase the logger.
How long does it take for the Bluetooth Datalogger to complete a measurement?
Total measurement time depends on the sensor or sensors being measured. There is always an initial
2 second power on delay, followed by the measurement sequence. Below is a breakdown of GPLP moisture
and temperature measurement times:
2 segment: 1.4 s
3 segment: 1.6 s
4 segment: 2.0 s
5 segment: 2.1 s
6 segment: 2.6 s
8 segment: 3.6 s
If you have multiple sensors connected, the measurement times add together. For example, to measure
three 8 segment GPLP sensors, total time is approximately 12.5 s.
What is the Local Log File feature and should I enable it?
The local log file feature logs all communication between the app and data logger. It is used for
diagnostics if there is an issue with the BTDL. Enable this only for diagnostics because it slows down
data download rates by roughly 15 percent.
What is the Daily Sampling feature?
Daily sampling conserves battery life by automatically adjusting the measurement interval based on
temperature readings from a connected GroPoint GPLP Profile sensor. The logger checks temperature at a
user defined time each day. If the temperature is below a user specified threshold, the logger switches
to a daily sampling interval. If the temperature rises above the threshold, the logger returns to the
regular measurement interval.
What format will data be downloaded in?
The default settings use .txt with a comma delimiter. This can be customized in the About menu of the
GP Reader app. Supported file formats are .txt, .csv and .dat, with comma, semicolon or tab delimiters.
Each reading in the parsed data files includes date and time, followed by the sensor address, moisture
measurements from each segment and then temperature measurements. For example, a 6 segment GPLP sensor
line might look like:
2024-03-08 14:53,0,+30.9,+54.2,+51.3,+16.6,+27.5,+26.6,+23.1,+22.3,+21.8,+21.3,+21
Submit a General Inquiry
Videos
GroPoint Tutorials: Data Logger Setup
Step-by-Step Guide: Set Up the Data Logger and Connect a Sensor
GroPoint Tutorials: Multiple Sensor Setup
Step-by-Step Guide: Set Up the Data Logger and Connect a Sensor
GroPoint Tutorials: Display Unit Setup
Step-by-Step Guide: Set Up the Data Logger and Connect a Sensor