Ethernet PLC5 Problem

[stan 0]

Everytime I change the IP address on a PLC5/40E it just comes back the same as the old one. I get the dialog asking me to confirm my IP changes but the address does not change. I did this by going offline making the change & then downloading, but still no success. I did not power cycle the PLC only switched to prog mode - could it be that the EEPROM is over-writing my changes. I notice that the Subnet & Gateway change to my desired setting but the IP doesn't. Can anyone help?

[OkiePC 14]

IS BOOTP Enabled? From RSLogix5 Help : "Click the check box to enable BOOTP. If enabled, this causes the PLC at powerup to try to obtain its network-related parameters (IP address, subnet mask, gateway address, etc.) via a BOOTP request. You cannot manually change the IP address if BOOTP is enabled. If you disable BOOTP, make sure that you have an IP address specified. If you change this field from enabled to disabled, the change does not take effect until you cycle power. © 1997 Rockwell Software Inc."

[stan 0]

BootP is DISABLED! The guys at AB tech support think the override is coming from the EEPROM, but this looks unlikely as the subnet & gateway would have been overwritten as well.

[Tim Ledwith 0]

Hi Stan, How are you physically connecting to the PLC to change the IP address ? Tim.

[stan 0]

I am connected to the PLC via a DH+ network... Does it make a difference? You may have a point, but pls let me know what if this makes a difference. Stan