ATS L20 Solar-Cell Tracker User Manual

: June 4, 2024
: ATS

Table of Contents

Section 1 Introduction
Section 2 Theory of Operation
Section 3 Using the Web Interface
Section 4 Interacting with the Tracker
Section 5 Tracker Functionality
Section 6 Attaching the Tracker
Section 7 Warranty and Service
Documents / Resources

L20 Solar-Cell Tracker
User’s Manual

IMPORTANT: Your L20’s SIM card has been activated for a 5-year period of service. After this period, ATS will contact the customer to determine if the data period should be renewed.
Trackers ARE NOT refurbished able. Do not return trackers for refurbishment service or disposal.

Section 1 Introduction

The L20 Solar-Cell Tracker is a lightweight, solar rechargeable, 4G LTE Cellular enabled GPS device. With indefinite battery life due to rechargeability, the L20 is well suited for use in multiple longer studies.
Tracker configuration and data download is done via web browser at ATSloggers.io. Login information will be sent by ATS sales.
IMPORTANT: Your tracker IS NOT ACTIVE until it is woken up with a magnet swipe. More details are in Section 4.
Data service HAS BEEN activated for all shipped L20 models.

Section 2 Theory of Operation

The L20 housing consists of a solar panel, rechargeable battery, GPS antenna, and GPS/4G LTE modem.
The tracker has a magnetic switch that is used for entering/leaving an ultra- low-power sleep mode where all schedules are paused. LED blink patterns to give feedback on what mode the tracker is in.
The tracker stores all location and sensor data in flash memory within the tracker’s electronics. The data is periodically uploaded via the 4G LTE Cellular modem and is stored in a cloud database. During the data upload, the tracker also checks the database for any user configuration changes that were made, such as scheduling and type of data to be collected, and updates settings accordingly. Data access and device configuration are both done within a web browser by the user.

Section 3 Using the Web Interface

All configuration and data downloads for L20 trackers are done via a simple browser web interface at atsloggers.io. This interface changes values within a cloud that the trackers connect to on each scheduled LTE session
Logging in
From any web browser, enter ‘atsloggers.io’ into the web address bar. This will bring up a login page, where users will enter their username/password that is delivered via email when first purchasing any L20 model.
Selecting a Tracker
The top of the webpage has a dropdown menu that gives access to all collars that are available to the user. Clicking on one of the choices in the menu populates current settings into the interface. The user is then able to select one of the three views for the tracker:

Configuring a Tracker
By default, after logging in, the user is brought to the tracker configuration page. This view is for changing schedule settings for the L20. The first slider changes how frequently the tracker tries to get a GPS fix. The second slider changes the interval between LTE data sessions, where the tracker sends its data and looks in the cloud for new schedule configurations.
IMPORTANT: the user MUST click the “Save New Configuration” button for schedule changes to take effect.
Downloading Data
By clicking “Tracker data”, the user is brought to a page that gives data download options. A date range can be chosen to only retrieve data within a specific time period, or all data from the tracker can be fetched. If hhmmss format is required on latitude and longitude, that can also be selected before downloading data.
Viewing Recent Transmissions
The final view that may be selected shows the recent LTE sessions and some statistics about the tracker at each event. The data shown are as follows:

Date/time
Number of GPS fixes sent by the tracker
Firmware version
Battery voltage

Section 4 Interacting with the Tracker

The L20 has an onboard magnetic switch to offer some user interaction, and an LED to give feedback on the operation.
Checking for Sleep mode
By quickly swiping a magnet near the L20’s internal switch, information can be found on what mode the tracker is in. When a magnet first comes in a range of the switch, the blue LED will turn on for two seconds, and then turn off. If there is a short blink after the LED turns off, then the tracker is asleep. If not, it is active and will take fixes/make transmits on the schedule.
Changing sleep mode
A magnet can also be used to change the sleep mode, prompting the tracker to enter deep sleep or start its data collection schedule.
To toggle modes, hold a magnet by the tracker’s switch. The LED will turn on for two seconds, and then turn off. When the LED turns off, quickly remove the magnet from the tracker. If successful, several LED blinks will indicate that the tracker has changed modes. Depending on the state that was entered, the blink pattern will vary, and this is shown in Table 1.
LED Blink Pattern Table
There are a number of events on the L20 that are indicated by LED blinks patterns, and the guide to each pattern is shown below in Table 1.

Interaction	LED pattern	Meaning
Quick magnet swipe	No blink	Tracker mode is Active
Quick magnet swipe	lx short blink	Tracker is in Deep Sleep
Magnet removed after LED off	No blink	No sleep-mode change, tracker is

Table 1: LED Blink Patterns

Section 5 Tracker Functionality

GPS Operation
A GPS attempt may last as long 180 seconds but may also be shorter depending on the collar’s view of the sky. In the case where a fix was not successfully found, no data will be recorded, and the tracker will continue on the schedule.
The GPS receiver specifications are shown in table 2:

Symbol	Description	Value	Unit
Sensitivity, cold	Acquisition sensitivity, cold start	-142	dBm
Sensitivity, hot	Acquisition sensitivity, hot start	-145	dBm

Sensitivity,
tracking| Tracking sensitivity| -151| dBm
TIFF, cold| Acquisition time (time to first fix (TIFF)), cold start, open sky, typical| 36| s
TIFF, hot| Acquisition time (TIFF), hot start, open sky, typical| 1.| s
Accuracy,
periodic| Positioning accuracy (CEP50), periodic tracking| 5| E
Accuracy,
continuous| Positioning accuracy (CEP50), continuous tracking| 3| m
Sensitivity, cold| Acquisition sensitivity, cold start| -142| dBm
---|---|---|---
Sensitivity, hot| Acquisition sensitivity, hot start| -145| dBm
Sensitivity,
tracking| Tracking sensitivity| -151| dBm
TIFF, cold| Acquisition time (time to first fix (TIFF)), cold start, open sky, typical| 36| s
TIFF, hot| Acquisition time (TIFF), hot start, open sky, typical| 1.| s
Accuracy,
periodic| Positioning accuracy (CEP50), periodic tracking| 5| E
Accuracy,
continuous| Positioning accuracy (CEP50), continuous tracking| 3| m

Table 2: GPS receiver specifications

4G LTE Transmission Operation
The L20 has an embedded Global IoT SIM card which allows it to communicate with LTE networks in most parts of the world. To check coverage in your country, visit https://www.hologram.io/pricing/coverage#coverage-table. If there is a dot that indicates 4G LTE coverage in the country of choice, most cell carriers will be able to connect to the L20 there.
During an LTE transmission, the data stored in flash is sent over cell networks, and once the data is confirmed as received, it is deleted from the tracker’s internal memory. In connection to the LTE network, the tracker also reads the current configuration from the cloud that is populated by the atsloggers.io website. Internal timers are updated in the case of a schedule change since the last connection.
Solar charging Operation
The L20 has an onboard solar charging circuit that is able to charge the battery in both high and low-light scenarios. There are separate battery thresholds for different events within the L20, as when the battery drops too low, activity is kept at a minimum in order to charge. In the case of an LTE transmission attempt, if the battery is too low to transmit, the L20 enters a mode where no GPS fixes are taken, and an LTE connection is attempted every 24 hours. This saves on power and will allow the battery to be brought out of a low-charge condition.
Rechargeable battery management is difficult in cold climates, where lithium- ion batteries can have issues when under load. Below freezing temperatures, the tracker is set to not attempt an LTE connection unless it is near a full charge. This is done in order to improve reliability and keep the battery from being damaged in cold temperatures

Section 6 Attaching the Tracker

The method of attaching the L20 to an animal varies on the exact model that was ordered.
Backpack Attachment
The backpack configuration has through-holes for feeding the wire through, creating loops to go around an animal’s limbs.
Collar Attachment
Your Collar(s) has been optimized according to the collar dimensions specified during ordering. The size of the collar is determined by the collar adjustment bracket and the main collar holes. To adjust the collar and/or attach the collar to an animal, the procedure is as follows (some differences may exist between models):

First, remove the collar adjustment bracket nuts and plate from the collar adjustment bracket and remove the collar adjustment bracket from the main collar.
Wrap the collar around the animal’s neck so that the extra length (if any) of the main collar is tucked inside the main collar end with the solar panels. The extra length can also be cut if desired.
Observe where the set of holes on the solar panel end of the main collar lines up with the holes on the other end of the main collar such as to maintain the desired tension level on the animal’s neck
Place the collar attachment bracket through both sets of holes and through the brass bracket and tighten the collar adjustment bracket nuts using the provided nut driver. Do not over-tighten as this may damage the collar adjustment bracket.
Finally, ensure that the case nuts have been tightened before releasing the animal.

Section 7 Warranty and Service

The model Collar(s) series collars are warranted for one year from the time of shipment.
NOTE: Collars ARE NOT refurbished able. Do not return collars for refurbishment or disposal.
Should you encounter any difficulty during the configuration or operation of your trackers, please contact ATS Sales and Service at 763.444.9267 during normal business hours. This and other ATS User Manuals, as well as software, are available for download from the ATS website, at www.atstrack.com.

Nov 18, 2021

Documents / Resources

| ATS L20 Solar-Cell Tracker [pdf] User Manual
L20 Solar-Cell Tracker, L20, Solar-Cell Tracker, Tracker
---|---
| ATS L20 Solar Cell Tracker [pdf] User Manual
L20 Solar Cell Tracker, L20, Solar Cell Tracker, Cell Tracker, Tracker
| ATS L20 Solar Cell Tracker [pdf] User Manual
L20, Solar Cell Tracker, Cell Tracker, Solar Tracker, L20, Tracker
| ATS L20 Solar Cell Tracker [pdf] User Manual
L20 Solar Cell Tracker, L20, Solar Cell Tracker, Cell Tracker, Tracker