As IoT grows and pierces more and more industry sectors, forward-thinking managers are looking for solutions for their problems and improvements in general.

One such manager, whose name we won’t mention, works for a very successful company in the commercial cooler sector. Among other services, they provide coolers and fridges for stores of all kinds – from large supermarkets to local mom&pop stores.

The company owns the fridges even when the fridges are in the store. Therefore, they want to monitor it in various ways. Of course, they have to do a little testing – a PoC. And because of their excellent taste, they’ve chosen our SimplePack to be their testing device and hopefully the solution they will deploy as well. This is what they expect:

First, they would like to receive regular temperature updates every 30 minutes. This is quite simple. Then, regular updates with the count of how many times the door was opened and closed during the monitored period. Plus, the location tracking as the owners of the stores should not move the fridges, but do it all the time anyway.

So… How can they solve this?

We have proposed three ways to do this and every single one is working with the reed contact sensor that switches on when a magnet is nearby. This means that a magnet will have to be inserted where the door touches the fridge when closed… Very easy!

• The first way to try this is to set the device to the Reed on/off WiFi mode with regular temperature updates sent every 30 minutes via a heartbeat message. This allows for precise localization as three MAC addresses are appended. There’s one drawback; it sends a message every time the door is opened and closed, which can be quite draining for the battery. Which means this is not applicable outside for deployment outside the PoC.

• The second is to operate in the Reed counter mode, which will send a number of reed switches (door openings) every 30 minutes, together with the temperature heartbeat. One MAC address will be appended to the heartbeat payload as well. This is great as it will let you know the number of door openings periodically. Even though the localization will not be as precise as the first option, one MAC address in the appended payload still means localization precision within tens of meters.

• The third is setting the device to the Reed contact pipeline mode which will send a message when the reed is switched on and with this message, time from the last reed switch. This allows the company to create a timeline of door openings – this data can be then used to further develop their service (knowing when the fridge is being used the most during the day etc). The message can be sent either every time the door opens or every 5 openings. The remaining settings are the same as above – temperature and one MAC address are appended.

So… What is the best solution? There is no such answer yet.

That’s what PoCs are for. The company will now begin the testing phase and see what works best. Throughout the PoC, we will assist them whenever needed and also go over the final results in order to help with the data analysis.

Best wishes,

Simple Hardware Team