Johnson Controls 300 Series User Manual

Network Control Module 300 Series Technical Bulletin 11
N1 Local Area Network
The N1 LAN allows communication with both OWSs and other
NCMs.
Whether you are using ARCNET card or Ethernet, each NCM and
OWS on the system contains a Node Manager task, whose
responsibilities include:
• broadcast once per minute that it is still online
• listen to other node managers to track on and offline trunks
• issue a time stamp for every global database in its memory
• compare the time stamps of its own databases to the received time
stamps of other node managers’ databases, and update the current
database if necessary
• monitor the printer for online or offline status
The node with the lowest address number on the network issues time
and date information once per day to ensure system synchronization. A
clock/calendar chip backs up time and date information. This Node
Manager also monitors broadcasts and issues online/offline advisories.
In the event of a severed N1 network, each separated LAN forms an
independent network.

Johnson Controls 300 Series Specifications

General

Brand	Johnson Controls
Model	300 Series
Category	Control Unit
Language	English