Online Versus Offline Controller Replacement - Metasys - LIT-12011829 - Field Device - VMA18 VAV Modular Assembly

N2 VMA Application Note

Product name
VMA18 VAV Modular Assembly
Document type
Application Note
Document number
Revision date

Characteristics of the N2 protocol used in the VMA1832 differ from those characteristics used in the VMA14xx controllers. To compensate, the new device must be defined using the VND (Vendor) Hardware Type instead of VMA.

To make this change online, you must delete the old device and all of its associated points and extensions. You may then add the new hardware device and rebuild all points and extensions.

Using SCT to make this change offline, you can edit the Hardware Type attribute without deleting any associated points. However, some of the old point definitions may not correspond to those defined in the new application CAF file and all points should be reviewed or remapped.

Making the change online takes longer, but making the change offline requires a full NAE download (not just a database synch) to bring the changes online.

Consider the impact on your customer when making the decision.