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OM 750
TABLE OF CONTENTS
Abbreviations Table ......................................................... 3
Safety Information ........................................................... 4
Introduction .................................................................. 5
Getting Started ............................................................... 5
Using the Local User Interface (LUI) ............................................. 5
2-digit 7-segment display ........................................................ 5
On/Stop Button and LED ......................................................... 5
Fan Button ............................................................................... 6
Mode Button ............................................................................ 6
Arrow Buttons ......................................................................... 6
Func Button ............................................................................. 6
Viewing Actual Temperature (IAT) ........................................... 6
Using the LUI to adjust Setpoint Offset ................................... 6
LUI Security Levels .................................................................. 6
Changing LUI Security Level .............................................. 6
Why can’t I use the Mode or Fan button,
or adjust Setpoint Offset? .................................................. 6
LUI Menu Reference ...................................................................... 7
Changing an LUI Menu Item .............................................. 7
Description of Operation ................................................... 9
State Programming ....................................................................... 9
UVC Unit Modes .......................................................................... 10
Off Mode ............................................................................... 10
Night Purge Mode ................................................................. 10
Fan Only Mode ....................................................................... 11
Emergency Heat Mode (Super State) ..................................... 11
Full Heat State ................................................................. 11
Cant Heat State ................................................................ 12
Auto Mode ............................................................................. 12
Heat Mode (Super State) ....................................................... 12
Heat State ........................................................................ 13
Low Limit State ............................................................... 13
Cant Heat State ................................................................ 13
Cool Mode (Super State) ....................................................... 14
Econ State ....................................................................... 15
Econ Mech State .............................................................. 15
Mech State ...................................................................... 16
Cant Cool State ................................................................ 16
DA Heat State .................................................................. 16
Low Limit State ............................................................... 16
Active Dehumidify State (optional,
software model 04) ..................................................... 17
Special Purpose Unit Modes .................................................. 17
Pressurize Mode .............................................................. 17
Depressurize Mode .......................................................... 17
Purge Mode ..................................................................... 17
Shutdown Mode .............................................................. 17
Energy Hold Off Mode ..................................................... 17
UVC Unit Mode Priority ......................................................... 17
Occupancy Modes ....................................................................... 18
Occupied Mode ...................................................................... 19
Unoccupied Mode .................................................................. 19
Standby Mode ....................................................................... 19
Bypass Mode ......................................................................... 19
Networked Occupancy Sensor Capability .............................. 19
Unit-Mounted Time-Clock ...................................................... 19
Unit-Mounted Tenant Override Switch ................................... 19
Remote Wall-Mounted Sensor Tenant
Override Switch ............................................................... 19
Remote Wall-Mounted Sensor Status LED ............................ 19
Space Temperature Setpoints ...................................................... 19
Networked Setpoint Capability ............................................... 19
Networked Setpoint Offset Capability .................................... 19
Networked Setpoint Shift Capability ...................................... 19
Networked Space Temperature
Sensor Capability ............................................................. 19
LUI Setpoint Offset Adjustment ............................................. 20
Remote Wall-Mounted Sensor with +/- 3
°
F
Adjustment (optional) ...................................................... 20
Remote Wall-Mounted Sensor with 55
°
F to 85
°
F
Adjustment (optional) ...................................................... 20
Effective Setpoint Calculation Examples ................................ 20
PI Control Loops ......................................................................... 21
Discharge Air Temperature Control ........................................ 21
PI Control Parameters ........................................................... 22
Proportional Band ................................................................. 22
Integral Time ......................................................................... 22
Indoor Air Fan Operation ............................................................. 23
Auto Mode ............................................................................. 23
Occupied, Standby and Bypass Operation ............................. 23
Unoccupied Operation ........................................................... 23
Cycle Fan ............................................................................... 23
Off Delay ................................................................................ 23
Outdoor Air Damper Operation .................................................... 23
Minimum Position ................................................................. 23
Economizer Operation ........................................................... 23
Temperature Comparison Economizer ............................. 23
Temperature Comparison with OA Enthalpy
Setpoint Economizer (optional) ................................... 23
Temperature Comparison with Enthalpy
Comparison Economizer (optional) ............................. 24
Networked Space Humidity Sensor Capability ....................... 24
Networked Outdoor Humidity Sensor Capability .................... 24
CO
2
Demand Controlled Ventilation (optional) ....................... 24
Networked Space CO
2
Sensor Capability ............................... 24
ASHRAE Cycle II .................................................................... 24
Compressor Operation ................................................................ 24
Compressor Envelope ............................................................ 24
Compressor Cooling Lockout ................................................ 25
Minimum On and Off Time .................................................... 25
Compressor Start Delay ......................................................... 25
Outdoor Air Fan Operation ..................................................... 25
Floating-point Actuator Auto-Zero, Overdrive and Sync ............... 25
External Binary Inputs ................................................................. 25
External Binary Input 1 .......................................................... 25
Unoccupied Input Signal ................................................. 25
Dewpoint/Humidity Input Signal
(optional, software model 04) ..................................... 25
External Binary Input 2 .......................................................... 25
Remote Shutdown Input Signal ....................................... 26
External Binary Input 3 .......................................................... 26
Ventilation Lockout Input Signal ...................................... 26
Exhaust Interlock Input Signal ......................................... 26
External Binary Outputs ............................................................... 26
External Binary Output 1 ........................................................ 26
Lights On/Off Signal ........................................................ 26
External Binary Output 2 ........................................................ 26
Fault Signal ...................................................................... 26
External Binary Output 3 ........................................................ 26
Exhaust Fan On/Off Signal ............................................... 26