Some M-Duino and Ardbox variants add a wireless option instead of, or alongside, wired communication. This lesson is a decision guide, not a tutorial for each radio, so you can pick the right variant before you order hardware.

What you will learn

• Compare WiFi, BLE, LoRa and GPRS/GSM by range, infrastructure and typical use.
• Ask the right questions about the installation site.
• Know why the choice must be made at purchase time.

Comparing the options at a glance

WiFi: when you already have a network

WiFi is the simplest option if the installation site already has WiFi coverage you are allowed to join. It gives you the same TCP tools you used in the Ethernet lesson, just without a cable. Ask the site IT team first: many plants restrict which devices may join the wireless network.

BLE: short-range, low-power, device to device

BLE fits short-range links to a nearby phone, tablet or gateway, for example a technician pairing to a machine for local configuration, rather than continuous plant-wide data collection.

LoRa: long range without a network to join

LoRa fits machines spread across a site where running Ethernet or relying on WiFi coverage is impractical, at the cost of a lower data rate. It needs a LoRa gateway to bridge back to your network, which is a separate piece of infrastructure to plan for.

GPRS/GSM: connectivity with no local infrastructure at all

GPRS/GSM fits remote sites with no WiFi, no Ethernet and no LoRa gateway nearby, using the cellular network instead. It depends on a SIM card and cellular coverage at the installation site, and typically costs more to operate than the other options here.

Choosing before you order hardware

The wireless option is a hardware variant you select at purchase, not something you switch later in software. Before deciding, answer these questions about the site:

1. Is there WiFi coverage at the machine, and may your device join it?
2. Is there cellular coverage at the machine?
3. Is a LoRa gateway already installed, or would you need to add one?
4. How much data do you send, and how often?
5. Who pays for and manages a SIM card or a gateway over the years?

Also check in the product catalog which wireless variants are currently available for your PLC family.

You are nearly done. Take the quiz below, then continue with Arduino PLC programming: industrial applications, where you build complete applications on top of these fundamentals.