Ethernet is what you reach for when a product has to be reliable, wired and reachable on the network that already exists in the building. Ambimat designs embedded systems with Ethernet interfaces — gateways, controllers and bridge boards that sit between industrial equipment and an IT network.
Where Ethernet is the right choice
Ambimat’s own position on this is deliberately narrow: Ethernet earns its place where data is going to a local network, staying inside the premises, or where the installation already has structured cabling and an IT team who would rather add a device to a VLAN than to a Wi-Fi SSID. Building automation is the clearest example, and it is where most of Ambimat’s Ethernet work has been done.
- Devices that report to a server on the same premises rather than to the internet
- Building and facility systems where cabling and IT policy already exist
- Gateways bridging serial field equipment to an IP network
- Installations where a wired link is required for determinism or for policy reasons
- Products that need a wired fallback alongside a wireless primary path
Ambimat’s Ethernet engineering experience
The clearest example is the AmbiAutomation HVAC bridge board. The problem it solves is that a building management system is rarely one vendor’s equipment: chillers, VRVs, VAVs, sensors and controllers arrive from different suppliers on different protocols, and something has to make them legible to one system. That board gathers data over RS-232 and RS-485 as well as over IP, and forwards it onward — and in one deployment it was configured to talk to equipment from Daikin, Delta, ABB and IFM in the same building.
The full account is in the HVAC systems case study, and the product itself is documented at the HVAC bridge board product page. For the wider building-automation offering, see AmbiAutomation.
What the engineering actually involves
On the hardware side: the PHY and magnetics, the RJ45 and its shielding, and isolation where the device shares an enclosure or a ground with field wiring — on the HVAC bridge board both the RS-485 and the RJ45 connectors are isolated, because in a plant room that is not optional. Beyond that it is the usual embedded work of getting a host controller, its power supply and its interfaces to coexist on one board.
On the firmware side: a network stack the product can actually maintain, addressing that survives contact with a real IT department — DHCP where the network offers it, static addressing where policy demands it — and an application layer that behaves when the link drops rather than only when it works.
Protocols Ambimat has worked with over Ethernet
These are drawn from delivered projects rather than from a datasheet, and not every project uses every one:
- BACnet and MODBUS for building automation equipment, including over IP
- JSON over HTTP to a back-end server, on an encrypted channel
- Serial field protocols over RS-232 and RS-485, bridged onto the IP network
Where a protocol is not on this list it is usually still a scoping question rather than a barrier — the point of a bridge product is that the field side changes per site.
Ethernet alongside other interfaces
Most of the products Ambimat has built with Ethernet do not use it alone. The same bridge board carries cellular and Wi-Fi options, because how a building gets its data out is a site decision and not a product decision. Designing for that means treating the uplink as a configurable layer rather than baking one into the hardware — which is a design choice that has to be made early, not retrofitted.
- Design by Technology — the full connectivity range
- Machine to Machine — the cellular uplink side