To connect an AC500-eco PLC to Automation Builder over Ethernet, give the PC a fixed IP on the same subnet as the PLC (for example 192.168.0.100/24 for a PLC at 192.168.0.10), use the IP configuration tool to find the CPU by its MAC address and set its IP, then select the Ethernet (TCP/IP) gateway route to that IP in the communication settings and log in.
- PC and PLC must share the same subnet: same first three numbers with mask 255.255.255.0
- The IP configuration tool finds CPUs by MAC address even when the IP is unknown
- On V2 eco CPUs the online route is the CoDeSys gateway with the TCP/IP (Level 2 Route) driver; on V3 it is the gateway scan in Communication Settings
- Ping first: if ping fails, Automation Builder will fail too
Almost every “cannot go online” call we get from students comes down to one of three things: the PC is on another subnet, the PLC has an unknown IP, or the wrong gateway route is selected. This lab removes all three.
Step 1: Plan the Network and Check the Subnet
Two devices can talk directly on Ethernet only when their network parts match. With mask 255.255.255.0 the first three numbers are the network and the last number is the device. Use the checker below before touching any setting.
Subnet checker
Type the PC and PLC addresses. The checker tells you whether they can talk directly.
| Device | IP address | Subnet mask | Note |
|---|---|---|---|
| Engineering PC | 192.168.0.100 | 255.255.255.0 | Fixed IP on the Ethernet adapter, no gateway needed |
| AC500-eco CPU | 192.168.0.10 | 255.255.255.0 | Commonly the AC500 factory default; confirm with the IP tool |
| CP604 HMI | 192.168.0.20 | 255.255.255.0 | Set on the panel's system settings |
Step 2: Give the PC a Fixed IP Address
- Open Control Panel > Network and Sharing Center > Change adapter settings.
- Right-click the Ethernet adapter connected to the switch and choose Properties.
- Select Internet Protocol Version 4 (TCP/IPv4) > Properties > Use the following IP address.
- Enter
192.168.0.100, mask255.255.255.0. Leave gateway and DNS empty. Click OK. - Turn Wi-Fi off during the lab if it is also on a 192.168.0.x network, to avoid routing confusion.
ipconfig in a command prompt shows 192.168.0.100 on the Ethernet adapter.Step 3: Find the PLC and Set Its IP with the IP Configuration Tool
If the CPU's IP is unknown (second-hand CPU, another project), you cannot ping it. The IP configuration tool in Automation Builder scans the network using the CPU's MAC address, which is printed on the CPU label, and lets you write a new IP.
- In Automation Builder open the IP configuration tool (from the Tools menu or by right-clicking the CPU in the device tree, depending on your version).
- Select the PC network adapter connected to the switch and click Scan.
- Find your CPU in the list by its MAC address.
- Enter IP
192.168.0.10and mask255.255.255.0, then send the configuration. Accept the CPU restart if asked. - Scan again: the CPU now shows the new address.
Click or tab to any device to see what you configure for it.
Step 4: Ping the PLC
ping 192.168.0.10
Reply from 192.168.0.10: bytes=32 time<1ms TTL=64 <- good
Request timed out. <- check cable, IP, subnetStep 5: Set the Gateway Route and Log In
The route to the PLC is set once per project and stored with it.
| CPU generation | Where to set the route | Setting |
|---|---|---|
| AC500-eco V2 (PM554/556/564/566) | Programming editor: Online > Communication Parameters | Local gateway, new channel with driver Tcp/Ip (Level 2 Route), address 192.168.0.10, default port |
| AC500-eco V3 (PM50xx) | Double-click the CPU > Communication Settings | Scan network on the gateway, select the CPU found at 192.168.0.10, set as active path |
- Create or open a project with the PM564-T-ETH CPU (you will build the full project in Lab 3).
- Set the communication route as shown in the table.
- Choose Online > Login. If the CPU has a different or no program, Automation Builder asks to download: answer No for now.
- Log out again with Online > Logout.
Practice Exercise
Change the PLC to 192.168.0.11 with the IP tool, update the communication route, log in, then put it back to 192.168.0.10. Use the subnet checker to explain why a PLC at 192.168.1.10 would not respond to your PC.
Troubleshooting
| Symptom | Likely cause | Fix |
|---|---|---|
| Ping times out | Different subnet, wrong adapter, cable | Use the subnet checker; check the link LEDs on the switch; disable other adapters |
| IP tool scan finds nothing | Wrong adapter selected or firewall blocking | Pick the adapter connected to the switch; allow Automation Builder through the firewall |
| Ping OK but login fails | Wrong gateway route or driver | Set Tcp/Ip (Level 2 Route) to the PLC IP (V2) or rescan the gateway (V3) |
| Connection drops when Wi-Fi is on | Two adapters on 192.168.0.x | Turn Wi-Fi off or move it to another subnet |
| IP changes back after power cycle | Setting not stored on the CPU | Resend from the IP tool and wait for the CPU restart to complete |
Frequently asked questions
What is the default IP address of an ABB AC500 PLC?
AC500 CPUs commonly ship with 192.168.0.10. Do not rely on it: scan with the IP configuration tool to see the real address.
How do I find the IP of an AC500-eco PLC I don't know?
Use the IP configuration tool in Automation Builder. It finds CPUs by MAC address on the connected network even if their IP is on another subnet, and lets you set a new IP.
Why can I ping the PLC but not log in from Automation Builder?
Ping proves the network path. Login also needs the correct gateway route: Tcp/Ip (Level 2 Route) to the PLC IP for V2 eco CPUs, or a scanned path in Communication Settings for V3 CPUs.
Do I need a gateway address on the PC?
No. When the PC and PLC are on the same subnet the default gateway can stay empty.
Can I program AC500-eco over serial instead of Ethernet?
Yes, ETH CPUs also support serial programming, but Ethernet is faster and is what this lab series uses.