Additional DCM replacement considerations - Metasys - LIT-12012005 - Field Device - N2 Controller - 13.0

Modernization Guide for N2 Controllers - Metasys

Product name
N2 Controller
Document type
User Guide
Document number
Revision date

When selecting transducers to replace OAP and OSV FMs, be sure to match the transducer output pressure range (psig or kPa) and volume (SCIM or SCCM) to the demands of the actuator.

Consider the following replacement selection guidelines:

  • Replace DCMs and all of their associated FMs at the same time.
  • Consider using BO, CO, or UO to replace FM relay outputs.
    • Review the electrical characteristics of the load device to ensure compatibility.
    • Ensure that the load is compatible with triac or FET output and current limits.
  • When replacing an ORM module, use start-stop signal mode of RO outputs of IOM modules.

If you plan to reuse the base-frame enclosure:

  • Be sure to verify that the base-frame enclosure still meets local codes because building codes change.
  • Use a separate 24 VAC power transformer for FECs/CGMs. Base-frame components use dedicated power supplies.
    • Remove and discard the NCU/NEU backplane assembly.
    • Co-located FEC/CGM and IOMs can use a common transformer.

When calculating power requirements, include all devices powered by the transformer.