Overriding Via The Nae - Johnson Controls TEC2627-2 Installation Instructions And Operators Manual

Adding a Thermostat
The thermostat must be added before its points can be
mapped. To do this, select the BACnet Integration
under the Field Bus (refresh the tree view if required to
see a newly added BACnet Integration) and choose
Field Device from the Insert menu. Assisted Definition
using Auto Discovery is the easiest way to add a new
thermostat online; however, this requires that the
thermostat that is to be added is connected and ready
to communicate.
Device object names used with BACnet
Communication must be unique to fully satisfy the
requirements of BACnet. The thermostat automatically
selects a device object name for itself using the format
TEC26x7-aaa, where aaa designates the address
selected (from 004 to 127) on the MS/TP network. If
this name needs to be changed by writing a new one
into the thermostat device object, that should be done
before any point objects are mapped. Be sure that the
name of the new thermostat being added to the NAE
matches that of the thermostat itself. This name goes
into the Name field, Object section, Configuration tab of
the Configure step in the Insert Field Device Wizard.
Device object IDs used with BACnet communications
must be unique to fully satisfy the requirements of
BACnet MS/TP network guidelines. The thermostat
automatically selects a device object ID for itself using
the format 72aaa, where aaa designates the address
selected (from 004 to 127) on the MS/TP network (for
example, 72004, 72005). If this ID needs to be
changed by writing a new one into the thermostat
device object, that should be done before any point
objects are mapped. Be sure that the ID of the new
thermostat being added to the NAE matches that of the
thermostat itself. This number goes into the Instance
Number field, Network section, Hardware tab of the
Configure step in the Insert Field Device Wizard.
14 TEC26x7-2 Series BACnet® MS/TP Networked Thermostats with Two Outputs Installation Instructions
Adding Point Objects
The required point objects must be mapped under the
thermostat device. To accomplish this, select the
thermostat device under the BACnet Integration
(refresh the tree view if required to see a newly added
thermostat device) and choose Field Point from the
Insert menu. Assisted Definition using Auto Discovery
is the easiest way to add new point objects online;
however, this requires that the thermostat that is to be
mapped is connected and ready to communicate.
When mapping point objects, the point type must
match the BACnet object type (for example, AV, MV,
BI), and the point instance number must match the
point BACnet instance number.

Overriding via the NAE

The last override command to any point object is used
or saved.
One override can be used at a time at each point object
(for example, if an override from the network is active,
the local adjustment and internal control are disabled).
If a setpoint is overridden, the thermostat adjusts the
other setpoint, if necessary, to maintain the minimum
deadband between the two setpoints. The setpoints
can be spread farther apart but can never be adjusted
closer than 2F°/1C° or the Deadband parameter
selection.
All network overrides are released automatically after
10 minutes of no communication to any other device
(for example, if the network cable is removed from the
thermostat). Other devices can be the NAE, another
thermostat, or a VAV Modular Assembly (VMA).