115
1.800.627.4499
DN-Series Integrated Programmable Controls
DOAS
SYSTEM MONITORING
The command to the fan is read at Analog Input 26 “SF_Command.Val.” The feedback from
the current sensor is read at Binary Input 15 “SF_Status.Val.” The actual flow rate is viewed at
Analog input 6 “OA_Flow_Rate.Val.”
The exhaust fan control type method can be viewed at Multistate Input 3 “EF_ControlType_BN.”
The valid values are 1 = Constant Speed, 2 = Exhaust Airflow, 3 = SF Command Tracking, 3 =
SF Flow Tracking, 4 = Return Static Pressure.
The corresponding settings are as follows:
u
Constant Speed setpoint is Analog Value 43 “EF_ConstantSpeedSetP.Val”
u
Exhaust Airflow setpoint is Analog Value 44 “EF_FlowControlSetP.Val”
u
Exhaust Fan Tracking setpoint is Analog Value 45 “EF_SF_TrackingSetP.Val”
u
Return Static setpoint is Analog Value 46 “EF_ReturnStaticSetP.Val”
The command to the fan is read at Analog Input 27 “EF_Command.Val.” The feedback from
the current sensor is read at Binary Input 16 “EF_Status.Val.” The actual flow rate is viewed at
Analog input 7 “EA_Flow_Rate.Val.”
13.5.5 Tempering Control
The DN DOAS unit may provide heating and cooling/dehumidification if ordered as such. For
heating and/or cooling, there will be a conditioned air temperature sensor which measured the
air coming out of the unit as Analog Input 32 “CA_Temp.Val.” For dehumidification with either
hot gas reheat or reheat by a heat source, there will also be a coil leaving temperature sensor
as Analog Input 29 “Cooling_LAT.Val.”
SA
T
T
Cooling
Heat Source
Coil Leaving
Temperature
CA
Temperature
13.5.5.1 Determining Tempering Mode
To determine the mode in which the unit is operating, the following values are considered:
u
Analog Value 73 “Dehumid_Chageover_SetP.Val”
u
Analog Value 48 “HeatLockoutTemp”
u
Analog Value 47 “CoolLockoutTemp”
In addition, the BMS has the potential to use one more setting to determine whether the unit
will lock out heating or cooling functions. This is required for the dual temp systems and may be
useful for other situations. The Binary Value 60 “BMS_SetHeatCool” must be true and then the
mode is set through Binary Value 61 “BMS_HeatCoolMode” where 0 =Heat and 1 = Cool. The
BMS mode is shown for troubleshooting.
