Understand what Bluetooth technology adds and gives up compared to battery-free RFID when talking about pick-to-light solutions.

As experts in battery-free sensor solutions, we have previously talked about pick-to-light solutions with battery-free RFID tags. We always recommend understanding your specific situation and assessing the best technology so today we wanted to share with you a different technology for the same application.

As you will see, it is not a matter of which technology fits better into the application itself but which technology fits better each specific implementation: focus on your specific needs!

Passive RFID for pick-to-light: a quick review

I’d like to keep it short here as you can visit the previous post about it. Basically:

  • Passive LEDs allow you to work with wireless LED tags – this helps with avoiding wiring, which can be really costly both during installation and in terms of maintenance over the years.
  • Moreover, the fact that they work battery-free means you will never have to incur into expensive maintenance due to battery changes.

However, you will find limitations on battery-free RFID LEDs for pick-to-light:

  • You may find out that the read range is too short for your idea. Remember that battery-free means the LED harvests the energy from the RF field created by the reader. This means the LED is only actionable when within the reader read range.
  • Initial power transfer can take a couple seconds, which may also be an issue for your application.

How Bluetooth LEDs can help in pick-to-light solutions

One of the main strength of Bluetooth over most of the wireless communication technologies is that you have an access point in most mobile phones. This makes it easily accessible and at a lower cost. However, note that you not always want to use such a standard technology.

Bluetooth LED for pick-to-light

Bluetooth LED for pick-to-light at Farsens

Anyway, no discussion in that Bluetooth add value over battery-free RFID:

  • Read range is significantly increased. If your needs include read ranges of 10-20 meters Bluetooth will still work for you without problem.
  • LEDs can be programmed to flash even if they are out of the read range of the reader. Since they have a battery to power them, that limitation is gone.
  • Brighter LEDs can be used, due to the fact that there is a power source available now – the battery

The main disadvantage of Bluetooth when compared to passive RFID is the battery dependency. You can probably select different batteries and increase sizes of the tags to improve the battery life. However, there will always be a point where you need to change the battery. Note that all LEDs in use will not be using the same amount of power so they will run out of battery at different times. This results in a complex maintenance in the long run. That being said, Bluetooth is probably one of the lowest power consumption technologies when moving into active wireless sensors, so this only grows worse if you move to Zigbee, WiFi or other technologies.

Again, there’s no one better solution for pick-to-light. You need to correctly define your solution and assess which one works best for you.