The LTD 2000 Series Geolocation Tags
- Overview
- Features
- Specifications
- Further Information
- Product Sheet
Designed principally as Geolocation tools, the LTD 2000 family tags are also highly effective Time, Temperature, Depth and Relative Light Level recorders.
- On-Board Geolocation algorithms provide daily estimates of Latitude and Longitude based on measured sunlight levels for the entire mission, regardless of mission length.
- Daily estimates of Sea Surface Temperature are recorded as a means of augmenting the Latitude by light level estimates when needed.
- Temperature, Depth, and Ambient Light Level data is recorded allowing the tag to double as a TDR or to allow post analysis of Geolocation data.
- Due to an advanced memory management feature, the time series log can be configured to telescope in time. This allows the total storage capacity of the tag to be evenly distributed over the entire mission without sacrificing the temporal resolution of the data for any day that time series data was logged.
- The crystal controlled Real-Time clock aboard each tag is temperature compensated. This results in a clock accuracy of 1 ppm. (~30 seconds / year) allowing for accurate correlation of data for Geolocation and other behavioral analysis.
- Ambient light intensity and external temperature is measured with a field proven "sensor stalk". The stalk allows these measurements when the body of the tag is implanted in the animal. Standard stalk length is 27 cm for the LTD 2310; custom lengths are also available.
- The ambient light is band pass filtered at 470nm matching the blue-green color of the ocean. This maximizes the depth at which geolocation can be performed.
- A selection of pressure ranges is available for each tag to match each application.
- The LTD 2310 is designed for 10+ years of service at depths of 2000 meters. The stainless steel housing is specifically designed to prevent salt penetration over long missions.
- The LTD 2310 geolocation tag is now available with an expanded memory option: 16 Mbytes
| SPECIFICATIONS |
LTD
2310 |
LTD
2350 |
| Physical Parameters | ||
| Diameter | 16 mm | 16 mm |
| Length | 76 mm | 76 mm |
| Weight in Air | 45 g | 45 g |
| Weight in Water | 30 g | 30 g |
| Casing | 316 Stainless Steel | 316 Stainless Steel |
| Sensor Stalk Length1 | 22 cm | 22 cm |
| Sensor Stalk Diameter | 2 mm | 2 mm |
| Sensor Stalk Material | Teflon | Teflon |
| Operating Temperature | -5 to +40°C | -5 to +40°C |
| Absolute Temp Range | -40 to +40°C | -40 to +40°C |
| Absolute Max Depth | 1.5 X Full Scale | 1.5 X Full Scale |
| Minimum Life | 2 years | 2 years |
| Typical Life | 2-4 years | 2-4 years |
| Real Time Clock | ||
| Temperature Compensated | Yes, 0 to +40°C | Yes, 0 to +40°C |
| Accuracy | 1 ppm | 1 ppm |
| Set at Factory | Yes | Yes |
| Memory | ||
| Type | Non-Volatile Flash | Non-Volatile Flash |
| Standard | 8 MByte | 16 MByte |
| Data retention | Battery Life +10 years | Battery Life +10 years |
| Day Log | Yes | Yes |
| Time series data | Telescoping available | Telescoping available |
| Time series data points | 1.33 Million X 4 Channels | 2.66 Million X 4 Channels |
| Time Series Interval | 4 to 5100 Sec. | 4 to 5100 Sec. |
| Delayed Start of Logging | Yes | Yes |
| Download Time | 3.8 minutes per Mbyte | 3.8 minutes per Mbyte |
| Other | ||
| Power Coil 3 | No 4 | No 4 |
| Communication (Optical) | 56k Baud | 56k Baud |
| Depth Sensing | ||
| Full Scale (F.S.) 5 | 2000 m | 2000 m |
| AutoScaling | No | No |
| Accuracy | ±1% F.S. | ±1% F.S. |
| Resolution | 0.05 % F.S. | 0.05 % F.S. |
| Max Depth | 1.5 X F.S. | 1.5 X F.S. |
| External Temp Sensing (Sensor Stalk) | ||
| Accuracy | ±0.1°C | ±0.1°C |
| Range 6 | 0 to +30°C | 0 to +30°C |
| Resolution | 0.05°C | 0.05°C |
| Response Time 7 | 3 Sec. | 3 Sec. |
| Internal Temp Sensing | ||
| Accuracy | ±0.1 C | ±0.1 C |
| Range 6 | 0 to +30°C | 0 to +30°C |
| Resolution | 0.05°C | 0.05°C |
| Response Time 7 | 20 Sec. | 20 Sec. |
| Light Sensing | ||
| Light Pipe (Sensor Stalk) | Yes | Yes |
| Sensor Type | Logorithmic | Logorithmic |
| Measurement Band | 470 nm ±50 nm | 470 nm ±50 nm |
| Sensitivity | 7 decades or better | 9 decades |
| Resolution | 32 points / decade | 32 points / decade |
| Response Time | 1 sec at 7 decades | 1 sec at 7 decades |
N.B. These specifications are preliminary & subject to change.
NOTES:
1. Custom Sensor Stalk lengths available.
2. Under normal operating conditions and single deployment.
3. User can recover data in the event of battery failure
only
4. Battery life normally exceeds mission length. Data
is factory recoverable should battery fail.
5. Optional depth sensing ranges available
6. Accuracy and Resolution degrades outside this range.
7. Time to reach 66% of step from 0 to 30 degrees.
More information on the use of LTD 2000 tags for geolocation studies can be found in the PDF document entitled Locating Tuna in the Open Ocean, available either from our Library page, or directly from here (PDF).
A paper evaluating the performance of the Lotek LTD 2310 archival tag can be viewed either from our Library page, or directly from here (PDF).
Information on inferring the surface irradiance from measurements made at depth can be found in the PDF document Correcting light at depth, available either from our Library page, or directly from here (PDF).
A paper describing a new threshold-free method of geolocation using sun light levels can be found in the PDF document An advance in geolocation by light, available either from our Library page, or directly from here (PDF).
LTD
2000 product sheet (PDF). 
The LTD 2000 series comes with data analysis software, TagTalk 2000, also available directly from our Downloads page.
