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RTU Open
i
Table of Contents
Introduction .................................................................................................................................................................. 1
What is the RTU Open controller? ...................................................................................................................... 1
Specifications ........................................................................................................................................................ 3
Safety considerations........................................................................................................................................... 4
Installation ................................................................................................................................................................... 5
Field-supplied hardware ...................................................................................................................................... 5
To mount the RTU Open ....................................................................................................................................... 6
To wire the controller for power.......................................................................................................................... 7
Using the rooftop equipment control power transformer ................................................................... 7
Using an auxiliary control power transformer ...................................................................................... 8
To set the RTU Open's address ........................................................................................................................... 9
To set the RTU Open's communications protocol and baud rate ............................................................... 10
Wiring the RTU Open to the MS/TP network ................................................................................................. 10
Wiring specifications ........................................................................................................................... 11
To wire the controller to the network ................................................................................................. 11
Wiring inputs and outputs ................................................................................................................................ 12
Input wiring specifications .................................................................................................................. 13
Inputs ................................................................................................................................................... 13
Binary outputs ..................................................................................................................................... 14
Analog output ...................................................................................................................................... 14
To wire inputs and outputs ................................................................................................................. 14
Wiring sensors to inputs ................................................................................................................................... 18
Field-supplied sensor hardware ......................................................................................................... 19
Wiring an SPT sensor .......................................................................................................................... 20
Rnet wiring specifications ........................................................................................................ 20
To wire the SPT sensor to the controller ................................................................................. 21
Wiring a Supply Air Temperature sensor ............................................................................................ 21
Wiring specifications ................................................................................................................ 22
To wire the SAT sensor to the controller ................................................................................. 22
Wiring a Duct Air Temperature sensor ............................................................................................... 22
Wiring specifications ................................................................................................................ 22
To wire a duct sensor to the controller ................................................................................... 23
Wiring an Outdoor Air Temperature sensor ....................................................................................... 23
Wiring specifications ................................................................................................................ 23
To wire an OAT sensor to the controller .................................................................................. 23
Wiring a CO2 sensor ............................................................................................................................ 24
Wiring specifications ................................................................................................................ 24
To wire the CO2 sensor to the controller ................................................................................ 24
Wiring an Outdoor Air Quality sensor ................................................................................................. 25
Wiring specifications ................................................................................................................ 26
To wire the OAQ sensor to the controller ................................................................................ 26
Wiring a Relative Humidity sensor ..................................................................................................... 26
Wiring specifications ................................................................................................................ 27
To wire the RH sensor to the controller................................................................................... 27
Wiring a Humidistat ............................................................................................................................. 27
Wiring specifications ................................................................................................................ 27
To wire a humidistat to the controller ..................................................................................... 28
Wiring an enthalpy switch ................................................................................................................... 28
Wiring specifications ................................................................................................................ 28
To wire an enthalpy switch (outdoor air) to the controller ..................................................... 29
To wire an enthalpy switch (differential) to the controller...................................................... 30