LoRa vs Zigbee for Existing RS485 Equipment: Which Actually Connects Without Rewiring?

What the Numbers Say About Your Existing Gear

Here’s a number that matters: over 65% of industrial equipment still uses RS232 or RS485 . PLCs, flow meters, temperature sensors—they’re out there, working fine, but stuck on serial connections. The global LoRa market reached $4.9 billion in 2024 , while Zigbee applications in industrial automation account for over 30% of deployments .

If you’re looking at LoRa or Zigbee, it’s probably because you already have devices in the field. You want their data on your network. Running new cable is expensive, disruptive, or just impossible.

Both LoRa and Zigbee work. But they’re not interchangeable. Picking the wrong one means fighting range issues, battery problems, or network headaches for years.

This guide focuses on what actually matters when you have existing RS485/RS232 equipment—not greenfield projects, not smart bulbs. Real installations that need to go wireless.

Quick Refresher (Only What You Need)

If you want deep technical specs, plenty of articles have them. Here’s the short version:

	LoRa	Zigbee
Range	Miles (6-8 km open)	Hundreds of feet (2 km open)
Frequency	410-525 MHz (sub-GHz)	2.4 GHz
Data Rate	Very low (300bps-37.5kbps)	Medium (20-250kbps)
Topology	Star, point-to-point	Mesh, star, tree
Power	Extremely low	Low to medium
Best for	Wide area, battery-powered, sparse sensors	Dense networks, reliable mesh, frequent data

According to technical analysis, Zigbee is best suited for large‑scale sensor networks like smart greenhouses, while LoRa excels in big‑area agricultural monitoring such as water‑saving irrigation

The Question Nobody Answers: How Do I Connect My Existing Gear?

Every LoRa vs Zigbee article compares chips and protocols. None tell you what to do with the PLC sitting on your plant floor with an RS485 port sticking out.

Here’s the reality: Neither LoRa nor Zigbee plugs directly into your equipment.

You need a bridge. A converter. Something that takes the serial data from your device and sends it over the wireless network you choose.

That’s where the rubber meets the road. And that’s where having both options—from the same supplier—makes your life easier.

If You Go LoRa

LoRa is for distance. Sensors spread across a farm. Tanks on opposite ends of a site. Equipment miles apart.

To connect your existing RS485/RS232 equipment to LoRa, you need a LoRa serial converter. It sits next to your PLC or meter, grabs the serial data, and sends it over LoRa to a gateway.

The gateway then forwards that data to your server or cloud.

What you’ll need:

One LoRa serial converter per device
One LoRa gateway (covers a large area)
Antennas, power supplies, cabling

The upside: One gateway can cover miles. If your devices are scattered, LoRa wins.

The downside: Data rate is low. If your equipment sends frequent updates or large chunks of data, LoRa might choke. Also, gateways cost more than Zigbee coordinators.

LoRa Products That Do This

VT-LR600: RS232/RS485/RS422 to LoRa Converter

This is your bridge. One at each device. Takes serial data, sends it over LoRa. Also receives and converts back to serial.

6-8 km range open area
-140dBm receive sensitivity (hears weak signals)
20dBm transmit power
410-525 MHz frequency (good penetration)
-40°C to 85°C operation
9-24V DC power
Metal enclosure

VT-LR601: LoRa to Ethernet Gateway

This sits at your control room or server location. Collects data from all VT-LR600s and puts it on your network as TCP/IP.

All the LoRa capabilities of VT-LR600
Adds 10/100M Ethernet
TCP/UDP/HTTP/DHCP/DNS support
Same industrial temp and power

If You Go Zigbee

Zigbee is for density. Factories. Buildings. Warehouses. Anywhere with multiple devices in a reasonably contained area. Zigbee operates at 2.4 GHz with data rates up to 250 kbps , and supports large‑scale self‑organizing networks .

To connect your existing RS485/RS232 equipment to Zigbee, you need a Zigbee serial converter—same idea as the LoRa version, but with Zigbee radio.

These converters join a mesh network. Each one can pass data for others. If one path fails, data goes another way.

At the top sits a Zigbee coordinator/gateway that collects everything and connects to your network.

What you’ll need:

One Zigbee serial converter per device
One Zigbee coordinator/gateway
Possibly extra routers if coverage is spotty (but your converters can act as routers)

The upside: Mesh is reliable. Add devices, and the network gets stronger. Data rate is higher than LoRa, so more frequent updates work.

The downside: Range per hop is shorter. You need enough devices to bridge the gaps. Not ideal for stuff scattered over square miles.

Zigbee Products That Do This

VT-ZB700: RS232/RS485/RS422 to Zigbee Converter

Your Zigbee bridge. One at each device. Takes serial data, sends it over Zigbee. Also acts as router in mesh mode.

2 km range open area
-105dBm receive sensitivity
25dBm transmit power
2.4 GHz frequency
Mesh/star/tree topology support
-40°C to 85°C operation
9-24V DC power
Metal enclosure

VT-ZB701: Zigbee to Ethernet Converter

Network coordinator and converter. Starts the Zigbee network, manages devices, converts data to TCP/IP.

All Zigbee capabilities of VT-ZB700
Adds 10/100M Ethernet
TCP/UDP/HTTP/DHCP/DNS support
Can work as TCP server/client/UDP
Includes virtual serial port software

Side-by-Side: Which Product for Which Job

Your Situation	LoRa Approach	Zigbee Approach
Devices spread over miles (farm, pipeline)	VT-LR600s + VT-LR601 gateway	Not ideal—range too short
Devices within one building/factory	Works, but overkill	VT-ZB700s + VT-ZB701 gateway
One device needs to talk to another, point-to-point	Two VT-LR600s	Two VT-ZB700s
Multiple devices reporting to central location	VT-LR600s + VT-LR601	VT-ZB700s + VT-ZB701
Battery-powered, need years of life	VT-LR600 (very low power)	VT-ZB700 (good, but mesh routing uses more)
Frequent data updates (seconds)	LoRa data rate may limit	VT-ZB700 handles higher rates
Harsh environment (outdoor, extreme temps)	Both lines: -40°C to 85°C, metal case	Same

The Hidden Cost of “Mesh” vs “Star”

Everybody talks about mesh like it’s magic. It’s not free.

Mesh pros (Zigbee): Reliable. Self-healing. Easy to extend—add a device, and it extends coverage automatically.

Mesh cons (Zigbee): Every device that routes uses more power. Network management is slightly more complex. If you have battery-powered sensors you want to last years, you might not want them routing traffic.

Star pros (LoRa): Simple. Devices sleep more. Gateways handle all the work.

Star cons (LoRa): If the gateway dies, everything dies. Coverage is what the gateway covers—no device-to-device relay.

Choose based on your reliability needs and power constraints.

What About Mixing Both?

Sometimes the answer isn’t either/or.

You might have a factory floor (Zigbee territory) with a remote tank farm half a mile away (LoRa territory). Nothing says you can’t use both.

Run Zigbee inside the building for dense, reliable mesh. Put a LoRa gateway at the edge to talk to distant assets. Bridge the two at the software level.

Your equipment doesn’t care. It just sends serial data. The converters handle the wireless part.