TROB24 Series Thermostat
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Introduction
This document provides information on using the Neptronic thermostat communications feature. This product
provides a BACnet
®
network interface between BACnet
®
client devices and Neptronic products. It uses the
BACnet
®
Master Slave/Token Passing (MS/TP) protocol at the BACnet
®
MAC layer.
This document assumes you are familiar with BACnet
®
and BACnet
®
terminology.
BACnet
®
Overview
Performance
The thermostat uses a synchronous implementation for BACnet
®
messages. Each BACnet
®
confirmed service
request is answered as quickly as possible without using Reply Postponed. In particular, MS/TP implementation
performs within Tusage_delay of 15ms in order to assure Tusage_timeout values within 20ms.
Support for MS/TP
The thermostat supports a Full Master Node state machine for MS/TP. All parameters are configured via the
thermostat menu or via the BACnet
®
WriteProperty service. Changes made via the WriteProperty take effect
immediately and does not require a restart of the thermostat. For more information on the configurable
properties, please refer to the
Getting Started
section on page 3. For more information on the thermostat menu,
please refer to the thermostat’s
Specification & Installation Manual
for more details.
BIBB Support
The thermostat generally behaves as a B-ASC type profile server. The following specific BIBBs are supported
per their relevant definitions in Annex K to BACnet
®
: DS-RP-B, DS-RPM-B, DS-WP-B, DS-WPM-B, DM-DDB-B,
DM-DOB-B, DM-DCC-B
Object Support (in general)
The thermostat supports a table-based fixed list of BACnet
®
-visible values which appear as Present_Values of
various BACnet
®
standard object types, in addition to a Device object.
Alarms
Although the thermostat supports the ability to indicate various alarm conditions through value changes in
properties of several of its objects, it
does not
generate BACnet
®
Event Notifications.
Features
Neptronic thermostats also offer the following time-saving features.
Auto Baud Rate Detection
The thermostat automatically configures its baud rate by detecting the network speed upon connection.
Auto Device Instance Configuration
The thermostat automatically configures its device instance to MAC address.
Copy Configuration
Copy the thermostat’s entire configuration and broadcast it to other thermostats of the same type on the
same network.
