With our production facility currently closed, some of us have been able to continue working from home and keeping up important discussions with customers (new and existing) about their upcoming requirements. One key thing we have learned here, though, is that it is likely that we will see fieldwork being delayed or postponed for significant periods of time, either due to a lack of safe working environments (e.g. social distancing), or with budgets being re-evaluated and resources being restricted.

So, with this in mind, I have written up this short, informative guide on best storage practice for your tags so that they can continue to contribute to your studies for as long as possible.

STORAGE

How should I store my tags?

We recommend that optimal storage for tags would be at room temperature, perhaps in a cupboard or a drawer. You should refrain from storing the tags in the fridge or in areas that are likely to get very warm as this will be detrimental for the battery. Due to their small size, the batteries are vulnerable to temperature extremities and, as such, have reduced performance levels in temperatures around 0°C and over 34°C.

When the tags are not in use, they should be stored in Deep Sleep mode to preserve battery life.

What will this mean for battery life?

Due to what’s called quiescent current draw, the tags will naturally lose battery power over time, even if they are not used. We estimate that the tags will lose approximately 1 month of battery life over a 12-month period whilst in Deep Sleep mode.

What is “quiescent current draw”?

It’s an electronics term which means “background current” – representing reduced battery voltage over time where electronic circuitry continues to run in the background, drawing current to power itself.

What is “Deep Sleep” mode?

Deep Sleep mode is the tag’s version of “standby”, where power can be saved by disabling primary operations. In this mode, a tag cannot log any data and does not maintain its internal clock. As a result, less of the electronic circuitry is used and the current draw from the circuit board is minimised, thus saving battery life.

You can activate Deep Sleep mode in one of two ways, but both require the use of the DST Host Software:

Once you have inserted a tag into an interface and selected “Connect”, you should navigate to the “Tag” tab along the top menu row and then select “Set Deep Sleep”.
Alternatively, if the tag has recorded data which has not yet been downloaded, you should proceed to “Download” this data first. Upon completing the download, the software will ask if you wish to store the tag in Deep Sleep mode.

Some additional things to consider:

All new tags are shipped to the customer in Deep Sleep mode
Placing a tag into an interface which is plugged into the PC will wake the tag out of Deep Sleep after 5 seconds, even without clicking “Connect” in the software
Deep Sleep mode is not activated automatically at any time
If you set Deep Sleep mode before the end of a deployment, then the tag will stop logging data at the time that Deep Sleep is activated
Likewise, if you set up a new deployment with the tag and then set Deep Sleep mode, the tag will not begin logging at your start date as it is not maintaining its internal clock. You should only
consider setting Deep Sleep mode after setting up a new deployment if the period between deploying the tag using the software and physically attaching the tag to a creature/object is more than a week or so. In that case, do not forget to manually set the clock (“Deploy” > “Set Clock”) before you release the tag, or it will not record any data!

DEPLOYMENT

Should I carry out any additional processes before deploying?

Yes, we suggest the following precautionary checks before deployment:

Visually check the tags – specifically, checking to see there are no clear defects on the outer casing or with the black urethane resin which covers the sensor
Connect to the tags using the DST Host software – you may need clean the communication pins with a pointed tool (such as a sharp, pointed scalpel) if these tags have been used previously, as there may be some debris/dirt present
Check the tag battery voltage – you can access live sensor readings by navigating to the “Tag” tab along the top menu row of the DST Host software, then selecting “View Sensors”. Whilst the battery voltage figure provided is only indicative, it will help you to set your expectations for tag performance. For example, if your tag displays a battery voltage <2.90V, then the tag is nearing the end of its lifetime and may only achieve a shorter deployment

What should I do if I cannot establish connection with the tag?

As mentioned previously, your first check should be to clean the communication pins. If the tag has been used before then it is quite possible that some dirt or debris could remain in the communication pins due to their concave shape. Any debris could block an electrical connection between the tag’s communication pins, and the spring pins in the interface (reader).
Secondly, you should check to see whether the PC you are now using is the same PC that
was used to connect to the tags previously. It may be that, whilst you have the DST Host software installed, you may not have the correct drivers for the USB interface installed on this machine. You can find the drivers on the USB stick provided with your order, or directly from the FTDI website: www.ftdichip.com/Drivers/VCP.htm
You should select the ‘setup executable’ option on the right hand side of the table, selecting from the row which matches your operating software.

If you have tried both steps above and still cannot communicate with the tags, it may simply be that the tag battery has expired.

What should I do if the tag battery has expired?

If you have data on the tag which you cannot retrieve due to battery expiry, please contact us on info@cefastechnology.co.uk and request to return your tag(s). We can carry out a free-of-charge data retrieval procedure to attempt to recover any data stored in the tag’s memory.

To conclude, we anticipate being able to reopen our production facility in the coming weeks, and so we remain available to receive orders and discuss your needs. Please do not hesitate to get in touch if we can be of assistance!

Stay safe, and we hope to speak to you soon.