GroPoint™ Bluetooth SDI-12 Data Logger
The GroPoint Bluetooth SDI-12 Data Logger is a wireless access point that lets you retrieve data from ANY SDI-12 sensor directly to your Android device via the free GP Reader app. Simply deploy it on-site to continuously monitor environmental metrics such as soil moisture, temperature, and EC. When you are ready to review your readings, just visit the site, press the logger's connect button, and wirelessly download your parsed data directly to your smartphone.
Key Features
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Natively connects up to 10 SDI-12 sensors, each with up to 60m (200ft) of cable, via the use of multiple M12 expansion bars.
- The SDI-12 V1.3 bus length limit is 600m (2000ft).
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4 MB capacity of safe data storage, even in the event of power loss.
- Approximately 20,500 soil moisture and temperature measurements from a 3-segment GroPoint Profile sensor.
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Long-life battery capacity can run for years depending on deployment. Two battery options are available:
- Default: 2x AA Lithium Metal (Included)
- Optional: 1x High-Performance Lithium Metal C-Cell (Purchased Separately)
- Zero recurring fees: Retrieve data locally via Bluetooth with no monthly subscriptions, cellular plans, or cloud service costs.
- Adapt on the fly: Wirelessly change sampling intervals and configuration settings directly in the field using the mobile app.
- Built for long-term outdoor deployment: Features an IP65, UV-stabilized, and corrosion-resistant enclosure.
- 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.
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
Downloads
Datasheets / Manuals
Bluetooth Data Logger Quickstart Guide Bluetooth SDI-12 Datalogger Manual Bluetooth SDI-12 Datalogger DatasheetSoftware
Smartphone / Tablet AppSubmit a General Inquiry
Product Tutorials
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