Addressing And Establishing Communications; Lonworks Network Addressing; Commissioning The Network; External Interface File (Xif) - McQuay MicroTech II Installation And Maintenance Manual

Addressing and Establishing Communications

LonWorks Network Addressing

Every Neuron Chip has a unique 48-bit Neuron ID or physical address. This address is generally used
only at initial installation or for diagnostic purposes. For normal network operation, a device address
is used.
Device addresses are defined at the time of network configuration. All device addresses have three
parts. The first part is the Domain ID, designating the domain. Devices must be in the same domain in
order to communicate with each other. The second part is the Subnet ID that specifies a collection of
up to 127 devices that are on a single channel or a set of channels connected by repeaters. There may
be up to 255 subnets in a domain. The third part is the Node ID that identifies an individual device
within the subnet.
A group is a logical collection of devices within a domain. Groups are assembled with regard for their
physical location in the domain. There may be up to 256 groups in a domain. A group address is the
address that identifies all devices of the group. There may be any number of devices in a group when
unacknowledged messaging is used. Groups are limited to 64 devices if acknowledged messaging is
used.
A broadcast address identifies all devices within a subnet or domain.

Commissioning the Network

Pressing the service pin generates a service-pin message, which contains the Neuron ID and the
program code identification of the node. A service-pin message is a network message that is
generated by a node and broadcast on the network. It can be used to commission the LonWorks
network.
A network configuration tool maps device Neuron IDs to the domain/subnet/node logical addressing
scheme when it creates the network image, the logical network addresses and connection information
for all devices (nodes) on the network.

External Interface File (XIF)

LonMark guidelines specify exact documentation rules so that proprietary configuration tools are not
required to commission and configure LonWorks devices. The MicroTech II LonWorks Chiller
Communications Module is self-documenting so that any network management tool can obtain all the
information needed over the network to connect it into the system and to configure and manage it. An
external interface file (a specially formatted PC text file with the extension .XIF) is also available so
that any network tool can design and configure it prior to installation. For a copy of the XIF file,
contact your local McQuay International representative.

Configuring the Unit Controller

The MicroTech II Chiller Controller LonWorks Communications Module is configured at the factory
as a chiller unit controller in accordance with the LonMark Chiller functional profile. The unit is
ready to operate with the default values of the various parameters set at the factory. Default values
may be changed via the network. See the appropriate operation manual for default values and keypad
operation and see the MicroTech II Chiller Protocol Information for descriptions of the network
variables. See Reference Documents for part numbers.
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