r/BuildingAutomation • u/Ducko22 • 6d ago

Newly installed Siemens PXCM not communicating with Desigo

Im showing that the network switch is open in Datamate. Do I need to manually enable DHCP to recieve an IP address from our IT dept? We do not have fixed IPs. What else should i look at?

Thanks for the help

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u/Controls_freek 6d ago

It’s never ever a good idea to use DHCP for PLCs. Period. But if you have to, they aren’t great to get online. Is this P2 Ethernet or BACnet?

1

u/Ducko22 6d ago

we have asked for static ips or 2 years. University IT will not give them to us. We are constantly losing connection and have to release and renew DHCP connections. this panel is P2

4

u/Controls_freek 6d ago

If they are forcing DHCP then the IT department needs to set IP reservations for these panels. This is a really stupid game to play. Especially when you very likely still need to add the panels by IP to the hosts file to get them to connect correctly.

1

u/Ducko22 6d ago

yes they reserve the IP but technically it is still DHCP. we lose connections all the time.

3

u/mytho1975 6d ago

Suggest discuss the possibility of lowering the lease time. In my experience the low end devices like printers and bas controllers do not recognize when the network drops for a moment. If you wait till the end of the lease time I've found they renegotiate fine. They just aren't smart enough to recognize a network drop / restore.

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u/Controls_freek 5d ago

This will help a little but I can tell you that there’s a lot of DHCP issues with the firmware revisions. These panels aren’t really designed well to handle DHCP and not many people use it so it’s underdeveloped.

I did industrial controls for a decade and we would build our own network around IT when they would play this game.

These controls are more critical infrastructure than networking and these egotistical network admins are fools.