Description of Operation

Figure 16: Effective set point calculations

Occupancy Temperature Setpoints (network configuration variables)

Occupied Cooling Set Point (OCS)

Standby Cooling Set Point (SCS)

Unoccupied Cooling Set Point (UCS)

Occupied Heating Set Point (OHS)

Standby Heating Set Point (SHS)

Unoccupied Heating Set Point (UHS)

Effective Set Point Calculations for each Occupancy Mode

AbsOffsetOccupied = Setpoint - (OCS + OHS)/2 AbsOffsetStandby = Setpoint - (SCS + SHS)/2

Space Temp Set Point Input (network input)

WallSensorType Config. Value

Set Point Offset Input (network input)

Network Value

 

55°F/85°F

1

Wall Sensor

0

+3°F/–3°F

 

Wall Sensor

Local User

Interface

+5°F/–5°F

Network Value

Set Point

SetptOffset

Occupied and Bypass Modes

EffectiveCoolSetpoint = OCS + AbsOffsetOccupied + SetptOffset + OCSS EffectiveHeatSetpoint = OHS + AbsOffsetOccupied + SetptOffset + OHSS

Standby Mode

EffectiveCoolSetpoint = SCS + AbsOffsetStandby + SetptOffset + SCSS EffectiveHeatSetpoint = SHS + AbsOffsetStandby + SetptOffset + SHSS

Unoccupied Mode

EffectiveCoolSetpoint = UCS + UCSS

EffectiveHeatSetpoint = UHS + UHSS

SetptShift (network inputs)

Occupied Cooling Set Point Shift (OCSS) Standby Cooling Set Point Shift (SCSS)

Unoccupied Cooling Set Point Shift (UCSS) Occupied Heating Set Point Shift (OCSS)

Standby Heating Set Point Shift (SHSS) Unoccupied Heating Set Point Shift (UHSS)

If both entering paths have valid values, then the network value has priority.

If both entering paths have

valid values, then the keypad/display value has priority.

Table 15: Set point calculation examples

Example A

Example B

Given

OccupancyMode = Occupied or BypassHeat/CoolMode = Heat

SpaceTempSetpoint = (not used)

SetpointOffset = (not used) = 0.0°F

SetpointShift = (not used) = 0.0°F

OHS = 69.8°F

Effective set point calculations

EffectiveSetpoint = OHS + SetpointOffset + SetpointShift = 69.8 + 0.0 + 0.0 = 69.8°F

Given

OccupancyMode = Occupied or BypassHeat/CoolMode = Heat SpaceTempSetpoint = 71.0°F

SetpointOffset = -1.0°F (occupant adjustment on remote wall sensor, or LUI) SetpointShift = (not used) = 0.0°F

OCS = 73.4°F, OHS = 69.8F

Effective set point calculations

AbsoluteOffset = (OCS – OHS) / 2 =(73.4°F – 69.8°F) / 2 = 1.8°F

EffectiveSetpoint = SpaceTempSetpoint – AbsoluteOffset + SetpointOffset + SetpointShift = 71.0 - 1.0 - 1.0 + 0.0 = 68.2°F

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McQuay OM 751

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American Standard UV05 manual Set point calculation examples, Example a Example B Given, Effective set point calculations