OPC Tag Database Manager Troubleshooting

If updating the value of one tag causes another to change its value as well, and there is no other configuration on the PLC which would do this automatically, you may have overlapping tag addresses.

This is most likely to occur with the below misconfigurations:

1. Two arrays are overlapping somewhere between their starting address and end of the array. You can shorten one of these arrays to ensure the memory address is only being accessed in one spot.
2. Both a single bit and the entire word value are being accessed via separate tags. If you do not require the entire word value, you can remove that tag. Otherwise, you may want to consider using bitwise statuses in Designer so you can still monitor that single bit and removing the bit tag.

It is recommended to not have overlapping values to avoid potential confusion.

If you have a PLC device and the tags become disconnected, but the PLC device is working properly and connected to the network, you may need to restart the OPC Tag Database service:

1. If the Tag Database Manager is opened, close it.
2. On the machine running the OPC Tag Database Manager, open Services.
3. Right-click the IPFusion - OPC Tag Database service and select Restart.

Once the service has restarted, the tags should now come online and the connection to the PLC should be restored.