### Troubleshooting networks If a controller is not communicating, select the controller's network on the WebCTRL® Network tree, then click the Devices button. This page shows the communication status of all controllers on the network. If all controllers on the network are not communicating, you have a network problem. Begin moving up the Network tree, checking communication status at each level to determine the starting point of the communications problems.
Click for details below Troubleshooting an IP/Ethernet connection Troubleshooting an ARCNET connection Troubleshooting BACnet bindings Working around supernetting limitations
#### Troubleshooting an IP/Ethernet connection Normal condition Most Ethernet devices have link lights that indicate connectivity. If the Ethernet cable is terminated correctly, the link lights at each port (server, Automated Logic® controller, and hub or switch) will be lit. A controller's LAN lights will flicker, indicating Ethernet data packet activity. Problem If the Ethernet connection is not wired correctly, you may experience the following symptoms: Link light is off LAN light remains off
Possible cause | Solution
--- | ---
The physical integrity of the cable or connectors is compromised. | If a known good cable results in a normal condition, replace the cable.
An improper connection type is used. | Use a crossover cable to connect two IP devices without a hub. Use a straight-through cable to connect an IP device to a hub.
A cable is plugged into a hub's uplink port. | Use a different port. NOTE Many hubs and switches share the first or last port with the uplink port. Other hubs have an uplink switch or button. If you need to use the first port, make sure that the hub or switch is set up correctly (usually a small switch on the back or bottom of the device) and that the first port is not shared with the uplink connection.
The devices are not on the same IP network. | Change one of the IP addresses or install an IP router. TIP To determine whether the devices are on the same network, use the Subnet calculator below.
Are Host 1 and Host 2 on the same network?
| Host 1 IP address: | ...
Subnet mask: | ...
Host 2 IP address: | ...
| Subnet Calculator by Treachery Unlimited
A NIC is installed incorrectly. | If you are unable to ping the host's IP address from the host computer, reinstall the NIC, checking for correct drivers.
Faulty hardware: NIC, hub, switch, or Automated Logic® controller | The diagnosis may be the same as the solution: replace the faulty hardware.

NOTES

- After checking these possible causes, if you are unable to get a link or LAN light on an Automated Logic® controller, contact Automated Logic® Technical Support.
- When troubleshooting an Ethernet connection, Automated Logic® Technical Support may request that you provide network diagnostics information from the System Configuration tree > Connections > Statistics tab.

#### Troubleshooting an ARCNET connection

Problem

Intermittent communication over an ARCNET network may cause the following symptoms:

- WebCTRL® graphics or properties pages intermittently display actual values then question marks.
- You can obtain a Modstat from a controller, but a download fails.

Possible cause

The WebCTRL® communication timeout settings are not sufficient for your network configuration.

Solution

Increase your communication timeout settings.

1. On the WebCTRL® System Configuration tree, select Connections.
2. On the Configure tab, select your BACnet/ARCNET Connection.
3. Click next to Tuning Parameters.
4. Double the values in the Comm Timeout and Comm Attempts fields.
5. Click Accept.

NOTE If changing these values does not fix your intermittent communication, contact Automated Logic® Technical Support.

#### Troubleshooting BACnet bindings

Every controller has a Device Binding Table that contains all Device IDs that the controller communicates with and the network address of each device. This typically includes the Device ID of the BACnet Alarm Recipient. If Network Address Translation (NAT) is enabled in SiteBuilder, the alarm recipient is omitted.

If the WebCTRL® application is not receiving alarms/trends or if the a point's value is incorrect, you can view this table to see where the controller is looking for its data.

1. On the WebCTRL® Network tree, select the controller that has incorrect or missing data.
2. On the Properties page, click Show Bindings.

EXAMPLE: If a controller has been sending alarm/trend data to Device 249999, but someone changed the BACnet Alarm Recipient field in SiteBuilder to 249996 and did not download parameters, the following information will be displayed at the bottom of the Device Binding Table:

`*** No binding for event recipient DEV:249999`
`*** Will not be able to deliver alarms/trend notifications`
`*** Alarms should be delivered to DEV:249996`

#### Working around supernetting limitations

What is supernetting?

Supernetting is a method of combining separate networks and making them behave as a single larger network using a common subnet mask.

Organizations are issued Class A (16777216 hosts), B (65535 hosts), or C (256 hosts) blocks of IP addresses based on how many hosts they have on their networks. If an organization needs 975 IP addresses, rather than being assigned one Class B block of IP addresses, it might be assigned four Class C blocks, or four different Class C networks. If the blocks are contiguous, they can be grouped together to behave as a single larger network.

EXAMPLE A subnet mask of 255.255.252.0 supernets these four Class C networks into one large network with a network number of 192.168.0.0 and a broadcast message number of 192.168.3.255:

192.168.0.0

192.168.1.0

192.168.2.0

192.168.3.0

The following Automated Logic® controllers support supernetting:

LGR line

ME-LGR line

ME812u-LGR

ME812u-E

To use WebCTRL® with a supernetted network

Although the LGE, LGRM-E, and WebPRTL do not support supernetting, the WebCTRL® server can communicate with these controllers if you set up the controllers and the WebCTRL® server on the same subnet as the default gateway and set their subnet masks (for Class C networks) to 255.255.255.0.

NOTE Your WebCTRL® server and the controllers may not be able to communicate with devices on other subnets that are part of the supernet.

EXAMPLE

Hardware | IP Address | Subnet mask
Default gateway | 192.168.1.16 | 255.255.252.0
WebCTRL® server | 192.168.1.30 | 255.255.255.0
LGE1 | 192.168.1.18 | 255.255.255.0
LGRM-E2 | 192.168.1.20 | 255.255.255.0
WebPRTL1 | 192.168.1.59 | 255.255.255.0