Just wonder whether is there IoT device which can support the following:
in-built 4g sim card slot
include driver to communicate with Rockwell/Siemens/Shneider PLCs
able to communicate with Ignition Gateway via MQTT
industrial use
I am using one industrial VPN modem and one Edge PC installed with Ignition edge, for each site, it works out well.
But it will be better if these two units can be combined as one unit.
Here is my two cents though, why do you need these two devices to be one? I use to want that as well but I realized separation of concerns in the hardware space is also very valuable. Think about it, you want a compute device (Ignition Edge/NodeRed etc) and a gateway (4G/Wifi/ETH/VPN etc) trying to get a device that is best in class for all those features is going to be hard to find. You will end up taking a device that is great in all aspects except for the fact that e.g. it has a crappy VPN feature. Having two separate devices also allows you to be agile in terms of new products on the market and hardware shortage.
Lastly, the gateway device is usually inexpensive compared to the compute device (look at Teltonika TRB140).
Maple systems have units that will cover points 2, 3 and 4. I don't believe they can accept a 4g card directly, they can how ever accept certain types of USB 4g modems.
Never went that route in the past as I always kept them separate. Maple systems device coupled with a ixon vpn 4g router.