A single cut cable, a failed port, or one accidentally unplugged drop should not be able to take down a production line. In a flat line or star network it can. Building the network as a redundant ring is the standard answer on the plant floor, and WAGO's 852 Lean Managed Switches were designed to make ring setup something a controls or maintenance team can do without a dedicated network engineer.

What is a ring network in industrial Ethernet?

A ring network is an industrial Ethernet topology where switches are cabled in a closed loop, so every device has two physical paths to the rest of the network instead of one. If a single link breaks - a severed cable, a dead port, a knocked-loose connector - traffic automatically reroutes the other way around the ring and the network keeps running. This redundancy is the whole point: in a line or star topology, one break isolates everything downstream of it.

The catch is that a closed loop of switches will, by default, create a broadcast storm that takes the network down. To run a ring safely, the switches have to be managed and running a redundancy protocol that logically blocks one path until it is needed. That is the line between an unmanaged switch and a managed one, and it is why you cannot build a real redundant ring out of plug-and-play unmanaged switches alone.

How ring redundancy actually works

Two protocols do the heavy lifting on WAGO's managed switches, and the difference between them matters when you are spec'ing for a fast process.

RSTP (Rapid Spanning Tree Protocol, IEEE 802.1w)

RSTP is the general-purpose redundancy protocol. It detects the loop, blocks one redundant path to keep the topology loop-free, and reconverges to the backup path when a link fails. It is interoperable across vendors and well understood, which makes it the safe default for mixed-vendor networks. Reconvergence is fast but not deterministic - it depends on the size and shape of the network.

ERPS (Ethernet Ring Protection Switching, ITU-T G.8032)

ERPS is purpose-built for rings and gives you deterministic, ring-specific recovery. On WAGO's managed 852 switches, ERPS supports multiple rings per switch and recovery on the order of a few hundred milliseconds after a fault, which is what you want when a network hiccup would otherwise drop a PLC connection mid-cycle. If your application is sensitive to even brief loss of communication - vision-guided handling, synchronized motion, tight process control - ERPS is the protocol to design around.

Backing both protocols up at the hardware level, the 852 managed switches accept a redundant DC power supply - two independent power inputs - so a single power fault does not drop the switch and defeat the whole point of the ring.

Why "Lean Managed" matters: ring setup without the IT overhead

Fully managed industrial switches are powerful, but their configuration depth is also a barrier - a lot of plants do not have a network engineer on staff to configure VLANs, ACLs, and a full L2 feature set just to stand up a redundant ring. That is the gap WAGO's Lean Managed tier fills. The Lean Managed switches reduce the parameter set to what a controls team actually needs, and expose it through a browser-based Web-Based Management (WBM) tool instead of a command line.

Through WBM you configure the ring, set redundancy parameters, and commission the switch from any browser on the network. The same interface gives you a live topology map of connected devices, per-port usage, and error diagnostics - so when something does go wrong, you are looking at a visual map of the network instead of parsing logs. WAGO's own factory case work makes the point directly: the Lean Managed Switch lets a user configure a ring network without extensive IT knowledge.

Lean Managed vs. Industrial Managed vs. unmanaged: which do you need?

A quick decision framework before the product specifics:

Switch tier	Ring redundancy?	Best for
Unmanaged / ECO	No	Simple point-to-point or star drops where uptime is not critical and budget is tight
Lean Managed	Yes (RSTP / ERPS)	Plants that need ring redundancy and diagnostics but want fast, browser-based setup without deep IT staffing
Industrial Managed	Yes (RSTP / ERPS)	Networks needing full L2 control - VLAN segmentation, MACsec/802.1X security, ACLs, fiber uplinks, extended temperature

WAGO 852 switches for building a redundant ring

Automation Distribution is an authorized WAGO distributor and carries the full 852 switch family. All of these are DIN-rail-mountable, accept a redundant DC supply, and run on industrial 24 V class power.

Lean Managed - the quick-setup ring switches

The WAGO 852-1812/010-000 Lean Managed Switch is the 8-port, 1000BASE-T workhorse for ring networks - eight Gigabit RJ45 ports, STP/RSTP, VLAN tagging, loop detection, a diagnostics dashboard and topology map, all managed through WBM. Need more drops on a single switch? The WAGO 852-1816 16-port Lean Managed Switch is the same concept with double the port count and a wider -40 to +60 degrees C range. Where you need Power over Ethernet for cameras, APs, or IP devices plus fiber uplinks, the WAGO 852-1813/010-001 Lean Managed Switch adds 8 x PoE and two SFP slots for 1000BASE-SX/LX, and its spec explicitly lists ERPS ring protection.

Industrial Managed - full L2 control and security

When the network needs hardened security or fiber backbones, step up to the Industrial Managed line. The WAGO 852-1322 Industrial Managed Switch adds MAC security to the 8-port Gigabit form factor, and the WAGO 852-1328 brings MACsec plus two SFP fiber slots in a 6-port build. For high-density backbones with fiber and PoE in extended-temperature environments, the WAGO 852-1505 and WAGO 852-1305 add four SFP slots each.

Unmanaged and ECO - for the non-redundant drops

Not every connection in a plant needs to sit on the ring. For straightforward star or point-to-point segments, the WAGO 852-1102 Industrial Switch and the cost-optimized WAGO 852-1112 ECO Switch give you rugged Gigabit connectivity without management overhead. Just remember: these cannot close a redundant ring on their own.

Closing the loop into your controller

A redundant ring exists to keep your control layer talking. WAGO designed the 852 switches and the PFC200 CODESYS controllers as parts of the same automation system - the switches carry Modbus TCP, EtherNet/IP, and PROFINET traffic between PFC200 nodes, I/O, HMIs, and SCADA, with the ring ensuring a single fault does not sever that path.

Frequently asked questions

Do I need a managed switch to build a redundant ring?

Yes. A closed loop of unmanaged switches creates a broadcast storm that brings the network down. You need a switch running a redundancy protocol (RSTP or ERPS) to logically manage the loop. WAGO's 852-1812 Lean Managed Switch is the entry point for this without full IT-grade configuration.

What is the difference between RSTP and ERPS?

RSTP (IEEE 802.1w) is a general-purpose, vendor-interoperable redundancy protocol; reconvergence is fast but depends on network topology. ERPS (ITU-T G.8032) is purpose-built for rings and delivers deterministic recovery on the order of a few hundred milliseconds, which is better for time-sensitive process and motion applications.

What is a Lean Managed switch?

A Lean Managed switch is a managed industrial switch with a streamlined, controls-focused parameter set and a browser-based Web-Based Management interface. It supports the redundancy and diagnostics features a plant needs - ring protocols, VLANs, loop detection, topology mapping - without the full configuration depth and IT expertise a fully managed switch demands.

Can I mix WAGO Lean Managed and Industrial Managed switches in the same ring?

In general, yes - as long as every switch in the ring runs a common, compatible redundancy protocol such as RSTP. A typical design uses Lean Managed switches at the cell level for quick setup and Industrial Managed switches like the 852-1322 where fiber backbones or MAC security are required. Confirm protocol settings match across the ring during commissioning.

How do I configure a ring on a WAGO 852 switch?

You configure it through the switch's Web-Based Management tool from any browser on the network - enable the redundancy protocol, define the ring ports, and the WBM topology map confirms the ring is closed and healthy. No command line is required, which is the core reason WAGO positions the Lean Managed line for plants without dedicated network staff.

Build your redundant network with Automation Distribution

Automation Distribution is an authorized distributor of WAGO automation and connectivity products. Start with the 852-1812 Lean Managed Switch for ring redundancy, scale to the 852-1816 or the Industrial Managed line where you need fiber and security, and pair them with WAGO PFC200 controllers for the control layer. Call 1-888-600-3080 to talk through your topology and match switches, power, and I/O to your application.