The honest answer is that it depends.
- On the condition the existing Metasys system and N2 bus
- On how much expertise your installation team has about Metasys and N2 devices
- On how much expertise your installation team has with the upstream protocol (i.e. OPC or BACnet)
- On the number of N2 devices you are integrating
- On your election to use the Upstream N2 Interface to co-exist with a legacy Metasys supervisory controller
- On how much custom programming you will need to deal with
- On the skill levels of your team working on the project
We can give you some general guidelines. You’ll need to extrapolate from there
- Assume that everything you need to do to bring your own brand of field device into your operator workstation you will need to do for Metasys devices
- Plan on using either the ComBus Quick Tester or the S2 device to validate the N2 bus on each network before you start the integration. Allocate contingency time to repair any
N2 bus problems or N2 devices that are not performing properly.
- Occasionally, you will run into extra-long N2 buses where the installer ignored the RS-485 standards and you will need to add repeaters. You also will occasionally run into cases
where a N2 bus has repeaters that are not working properly and you will need to replace them.
- Assume that you may need to develop custom graphics for the Metasys devices instead of using pre-defined templates designed for your own technology.
- You need to decide if our standard device type templates (point mappings) are OK for the N2 Open and VMA devices. If you want to generate custom templates using our conversion
utility with .prn files as input it will take you a bit longer.
- If you have DX-9100 systems in the configuration these will each require you to utilize the associated .DMO file and our conversion utility to generate a custom template. The custom
templates will then need to be manually assigned to the N2 devices. It only takes a few seconds to do the assignment but it is an additional step you need to take.
- If you have Vendor (VND) devices or Metasys Integrator (MIG) devices these may require the development of custom templates and then manual assignment of the templates in the
same way described above. We’ll help you through this process as part of our support of the installation so there are no associated charges. However, we will need to rely on you to provide
documentation and to do the final validation of the point mapping in the field since it is unlikely that we have similar devices in our test lab.
- If you have any N2 Open devices running the Point Multiplexer application or XT / XTM devices directly on the N2 bus you will need to determine how these generic points were being used by
the Metasys head end and replicate any required supervisory logic.
- If they still have any of the early generation Network Control Unit (NCU) or Network Expansion Unit (NEU) chassis in service you will need to deal with the associated NCM and I/O cards. This is a
significant effort but can be handled successfully with appropriate planning. There are multiple articles on our web site about how to handle these devices. If you do have any of these devices
contact The S4 Group to develop an appropriate strategy.
The mechanics of installing the N2 Router and running our Configure Wizard can be completed in a couple of hours. Most integrations go very smoothly. But, the devil is in the details. Learn all that you can about the configuration and then add time as appropriate. Be conservative, especially if this is probably your first time through the process. If you are not sure, err on the side of allocating a bit more time. In a large installation it wouldn’t be unusual to plan on working on each Metasys network for a couple of days and then throw in some contingency time just in case you run into a network that doesn’t want to cooperate.