Metasys UNT141-1 - User Manual

Application Specific Controllers Technical Manual 636.3
UNT Controller Section
Technical Bulletin
Issue Date 0398
© 1998 Johnson Controls, Inc.
1
Code No. LIT-6363081 www.johnsoncontrols.com
Introduction Page 5
• Description 5
• Standards Compliance 6
Configuring the Controller 7
• Using HVAC PRO for Windows Configuration Tool 7
• Defining a UNT Control Device Object *7
• Defining a UNT Control Device in Companion Software 9
Installation Procedures 11
• Design Considerations *11
• Tools Needed *11
• Environmental Information 12
• Mounting the Controller *12
• Power Line Wiring Transient Noise Precautions *16
• I/O and Communications Wiring Transient Noise Precautions 18
Wiring Details 19
• Power Source and Loads *19
• Wiring Precautions 21
• Grounding and Isolation UNT110/111, 120/121, 140/141 22
• Grounding and Isolation UNT110/111, UNT120/121,
and UNT140/141 with Separate Load Transformer *23
Unitary Controller (UNT)
* Indicates those sections where changes have occurred since the last printing.

Metasys UNT141-1 Specifications

General

Model	UNT141-1
Input Voltage	24 VAC
Power Consumption	10 VA
Communication Protocol	BACnet MS/TP
Enclosure Rating	IP20
Type	Controller
Operating Temperature	-40°C to 70°C
Relative Humidity	10% to 90% non-condensing
Inputs	Universal (Analog/Digital)
Dimensions	6.1 in. x 4.8 in. x 2.0 in. (155 mm x 122 mm x 51 mm)

Summary

Introduction

Configuring the Controller

Using HVAC PRO for Configuration

Guide on using HVAC PRO software for UNT configuration and commissioning.

Defining Control Device Objects

Steps to define UNT device objects in Metasys Network System and Companion software.

Installation Procedures

Wiring and Noise Precautions

Power Line Noise and Surge Levels

Details power line surge levels and precautions to prevent transient noise.

I;O and Communications Wiring Noise

Guidelines for clean I/O wiring and N2 Bus to prevent noise interference.

Wiring Details

Grounding and Isolation

Procedures and diagrams for grounding and isolating UNT controllers.

Input;Output Configuration

Unit-Mounted Control Wiring

UNT110;111, UNT120;121 Wiring

Sensor and Actuator Wiring

Sharing Sensors Among UNTs

Multi-UNT Sensor Sharing Procedure

Networking the Controller

Installing and Setting the N2 Address

Procedure for installing the N2 Bus and setting the UNT's N2 address using DIP switches.

N2 Wiring to Control Modules

N2 Wiring to Companion

Zone Bus Communications

Description of the Zone Bus for UNT communication with actuators and terminals.

Application Examples

Downloading and Commissioning

Troubleshooting

UNT Controller Troubleshooting

Table of possible controller malfunctions and corrective actions using HVAC PRO for Windows.

N2 Bus and Zone Bus Troubleshooting

Steps to troubleshoot N2 Bus and Zone Bus communication problems and errors.

Isolation and Grounding Procedures

Isolation without Earth Ground

Grounding with Earth Connection

Guidelines for making an earth ground connection to the common terminal of UNT controllers.

Ordering Information

Specifications

UNT Controller Specifications

Technical specifications for UNT controllers, including operating conditions, dimensions, and interfaces.

Appendix A: Rooftop Installation Precautions

Rooftop Unit Noise, Resets, and Gas Ignition

Appendix B: UNT100;101 Specifics

UNT100;101 Isolation, Grounding, and I;O

Procedures for isolation, grounding, and binary I/O for UNT100/101 controllers.