Advanced Parameters

Advanced parameters of the AHU application are available directly from the iSMA Tool/iC Tool. After connecting and logging into the AAC20 controller, expand the device tree, and go to the Logic folder. In the expanded Logic folder, there are the main functional modules.

Functional modules (except Inputs, Outputs, Setpoints, Config, and General) contain the Parameters subfolder with advanced parameters allowing to tune the AHU application to the air handling unit to be controlled. Most of air handling unit types do not require changes and can remain with default values (changed only in special implementations). The parameters that may typically be needed for fine-tuning are usually loop settings, but in many cases the defaults are sufficient.

Note: Advanced parameters are available only from the iSMA Tool/iC Tool level - they are not available from the LCD, web server or via BACnet IP/Modbus TCP.

The list of available advanced parameters divided into functional modules:

Dampers

No	Name	Description	Range	Default	Units
1	MAT_MinSetpoint	Minimum mixed air temperature setpoint	0-50	10	°C
2	MAT_MaxSetpoint	Maximum mixed air temperature setpoint	0-50	15	°C
3	MAT_P_band	Mixed air temperature control P-band	0.01-100	10	100/K
4	MAD_RunTime	Actuator damper runtime - 0=disable runtime	0-1440	150	sec
5	OAT_MinSetpoint	Minimum outside air temperature	-50-50	-10	°C
6	OAT_MaxSetpoint	Maximum outside air temperature	-50-50	10	°C
7	DMS_MinPosition	Minimum damper position	0-100	20	%
8	DMS_MaxPosition	Maximum damper position	0-100	100	%
9	DMS_StartRatioControl	Ratio damper control signal sequence start	0-100	0	%
10	DMS_StopRatioControl	Ratio damper control signal sequence stop	0-100	100	%
11	DMS_RatioEnable	Ratio damper control signal enable - true=enable	False/true	False	N/a
12	DMS_RampTime	Ramp time damper control signal	1-100	10	%/min

Advanced parameters for dampers

Exchanger

No	Name	Description	Range	Default	Units
1	ERT_MinSetpoint	Exchanger temperature low setpoint	0-50	10	°C
2	ERT_MaxSetpoint	Exchanger temperature high setpoint	0-50	15	°C
3	ERT_P_band	Exchanger temperature control P-band	0.01-100	10	100/K
4	OAT_MinSetpoint	Minimum outside air temperature	-50-50	-10	°C
5	OAT_MaxSetpoint	Maximum outside air temperature	-50-50	10	°C
6	OAT_FrostProtection	Low limit frost protection	-50-50	6	°C
7	ERS_MinRecovery	Minimum exchanger control signal	0-100	0	%
8	ERS_MaxRecovery	Maximum exchanger control signal	0-100	100	%
9	ERS_StartRatioControl	Ratio exchanger control signal sequence start	0-100	0	%
10	ERS_StopRatioControl	Ratio exchanger control signal sequence stop	0-100	100	%
11	ERS_RatioEnable	Ratio exchanger control signal enable - true=enable	False/true	False	N/a
12	ERP_OffDelay	Exchanger pump switch off delay	0-3600	300	sec
13	ERP_StatusAlarmDelay	Delay status alarm - 0=disable, 1=failure, <0=fail-to-command alarm, >1=status alarm	-600-600	1	sec
14	ERP_Pmp_Vlv_Exercise	Exchanger pump / valve exercise time	0-600	120	sec
15	ERP_WheelRelease	Wheel release - false=plant mode, true=continuous	False/true	False	N/a
16	ERP_OnDelay	Start-up delay pump / wheel	0-300	5	sec

Advanced parameters for exchangers

Preheater

No	Name	Description	Range	Default	Units
1	RWT_LowSetpoint	Return water temperature low setpoint	0-100	10	°C
2	RWT_HighSetpoint	Return water temperature high setpoint	0-100	25	°C
3	RWT_MaxSetpoint	Return water temperature maximum setpoint	0-100	85	°C
4	RWT_P_band	Return water temperature control P-band	0.01-100	10	100/K
5	DME_OnDelay	Damper enable or alarm delay - 0=alarm disable	0-3600	300	sec
6	DME_EmergencyStop	AHU stops on pump alarm at low outside air temperature - true=yes	False/true	False	N/a
7	OAT_MinSetpoint	Outside air temperature minimum value	-50-50	-10	°C
8	OAT_MaxSetpoint	Outside air temperature maximum value	-50-50	10	°C
9	OAT_FrostProtection	Low limit frost protection	-50-50	6	°C
10	FEZ_RWT_SptUp	Frost protection return water temperature setpoint raise	0-50	15	K
11	FEZ_SetupRamp	Raised setpoint decrease during frost recovery	1-20	1	K/min
12	HPU_OnDelay	Start-up delay heating pump	0-300	5	sec
13	HPU_OffDelay	Heating pump switch off delay	0-3600	300	sec
14	HPU_Enable	Heating pump enable - true=enable	False/true	True	N/a
15	HPU_Pmp_Vlv_Exercise	Heating pump and valve exercise time	0-600	120	sec
16	HPU_StatusAlarmDelay	Delay status alarm - 0=disable, 1=failure, <0=fail-to-command alarm, >1=status alarm	-600-600	1	sec
17	HTS_StartRatioControl	Ratio control signal sequence start	0-100	0	%
18	HTS_StopRatioControl	Ratio control signal sequence stop	0-100	100	%
19	HTS_RatioEnable	Ratio control enable - true=enable	False/true	False	N/a
20	HTV_FrostProt_ValveUp	Heating valve position during frost protection	0-100	100	%
21	HTV_Ramp	Heating valve raised position decrease during frost recovery	1-100	10	%/min

Advanced parameters for preheaters

Cooler

No	Name	Description	Range	Default	Units
1	OAT_CoolerLowLimit	Low limit outside air temperature - cooler valve closed	-50-50	14	°C
2	CCV_VlvRamp	Valve position increase per minute	1-100	5	%/min
3	CCV_MinVlvPos	Minimum valve position	0-100	0	%
4	CCV_MaxVlvPos	Maximum valve position	0-100	100	%
5	CCV_Vlv_Exercise	Cooling valve exercise time - 0=disable	0-600	120	sec
6	CCS_StartRatioControl	Ratio temperature control sequence start	0-100	0	%
7	CCS_StopRatioControl	Ratio temperature control sequence stop	0-100	100	%
8	DEH_StartRatioControl	Ratio dehumidification control sequence start	0-100	0	%
9	DEH_StopRatioControl	Ratio dehumidification control sequence stop	0-100	100	%
10	CCS_RatioEnable	Ratio temperature control enable - true=enable	False/true	False	N/a
11	DEH_RatioEnable	Ratio dehumidification control enable - true=enable	False/true	False	N/a
12	CCV_CoolOnHumDisable	Disable cooling on humidify - true=yes	False/true	True	N/a
13	LIM_Setpoint	Low limit setpoint	0-50	14	°C
14	LIM_P_band	Low limit P-band	0.01-100	10	100/K
15	LIM_I_time	Low limit I-time	0-1000	0	100/sec

Advanced parameters for coolers

Reheater

No	Name	Description	Range	Default	Units
1	OAT_FrostProtection	Low limit frost protection	-50-50	6	°C
2	HPU_OnDelay	Start-up delay heating pump	0-300	5	sec
3	HPU_OffDelay	Heating pump switch off delay	0-3600	300	sec
4	HPU_Enable	Heating pump enable - true=enable	False/true	True	N/a
5	HPU_Pmp_Vlv_Exercise	Heating pump and valve exercise time	0-600	120	sec
6	HPU_StatusAlarmDelay	Delay status alarm - 0=disable, 1=failure, <0=fail-to-command alarm, >1=status alarm	-600-600	1	sec
7	HTS_StartRatioControl	Ratio control signal sequence start	0-100	0	%
8	HTS_StopRatioControl	Ratio control signal sequence stop	0-100	100	%
9	HTS_RatioEnable	Ratio control enable - true=enable	False/true	False	N/a
10	HTV_FrostProt_ValveUp	Heating valve position during frost protection	0-100	100	%
11	HTV_Ramp	Heating valve raised position decrease during frost recovery	0-100	10	%/min

Advanced parameters for reheaters

Fans

No	Name	Description	Range	Default	Units
1	FDP_BeltAlarmDelay	Delay fan belt alarm - 0=disable	0-600	120	sec
2	FSC_OffOnDelay	Delay fan start/stop	0-600	5	sec
3	FSC_Ramp	Control signal increase per minute	0-100	1	%/min
4	FSC_MinSignal	Minimum fan speed control signal	0-100	30	%
5	FSC_MaxSignal	Maximum fan speed control signal	0-100	100	%
6	FSC_ManualReset	Manual / automatic alarm reset - false=manual	False/true	False	N/a
7	DSP_PressSptRamp	Setpoint increase per minute	0-1000	50	Pa/min
8	DSP_PressDisP_band	Static discharge pressure control P-band	1-1000	0.5	100/Pa
9	DSP_PressRetP_band	Static return pressure control P-band	1-1000	0.5	100/Pa
10	DSP_PressDisI_time	Static discharge pressure control I-time	0-1000	0	100/sec
11	DSP_PressRetI_time	Static return pressure control I-time	0-1000	0	100/sec
12	DSP_NightReduce	Night reduction of control signal	0-100	50	%

Advanced parameters for fans

Humidifier

No	Name	Description	Range	Default	Units
1	OAT_HighHum	High limit for humidification	-50-50	14	°C
2	OAT_LowDeh	Low limit for dehumidification	-50-50	15	°C
3	RAH_MinHumSpt	Minimum room humidity setpoint during winter	0-100	30	%RH
4	RAH_MaxHumSpt	Maximum room humidity setpoint during summer	0-100	60	%RH
5	RAH_P_band	Relative room/return humidity control P-band	0.01-100	25	100/%RH
6	RAH_I_time	Relative room/return humidity control I-time	0-1000	0	100/sec
7	WC_LowOAT	Start point outside air temperature winter compensation	-50-50	-10	°C
8	WC_HighOAT	End point outside air temperature winter compensation	-50-50	10	°C
9	SC_LowOAT	Start point outside air temperature summer compensation	-50-50	20	°C
10	SC_HighOAT	End point outside air temperature summer compensation	-50-50	30	°C
11	DAH_MaxSpt	Maximum setpoint discharge air relative humidity	0-100	90	%RH
12	DAH_P_band	Maximum setpoint control P-band	0.01-100	8.33	100/%RH
13	DAH_LowAbsHumSpt	Discharge air absolute humidity low setpoint	0-25	5	g/kg
14	DAH_HighAbsHumSpt	Discharge air absolute humidity high setpoint	0-25	15	g/kg
15	HUM_P_band	Humidification control P-band	0.01-100	25	100/%RH
16	HUM_RampUp	Relative humidity control signal increase per minute	1-100	10	%/min
17	HUM_FanOnDelay	Delay after fan start	0-3600	300	sec
18	HUM_StatusAlarmDelay	Delay status alarm - 0=disable, 1=failure, <0=fail-to-command alarm, >1=status alarm	-600-600	1	sec
19	DEH_P_band	Dehumidification control P-band	0.01-100	16.67	100/%RH
20	DEH_RampUp	Relative humidity control signal increase per minute	1-100	10	%/min
21	HUMDEH_I_time	Humidify / dehumidify control I-time	0-1000	0	100/sec
22	HUMDEH_ComfZone	Comfort zone between humidify / dehumidify	0-40	4	%RH

Advanced parameters for humidifiers

Economizer

No	Name	Description	Range	Default	Units
1	AtmPressure	Atmospheric pressure	80-120	101.30	kPa
2	EnthalpyDiff	Enthalpy difference	0-20	5	kJ/kg
3	AbsHumDiff	Absolute humidity difference	0.0-5.0	1	g/kg
4	SwitchoverDel	Switch over delay	0-1800	300	sec

Advanced parameters for the economizer function

Control

No	Name	Description	Range	Default	Units
1	OAT_HeaterLimit	Limit outside air temperature - heater closed	-50-50	20	°C
2	OAT_CoolerLimit	Limit outside air temperature - cooler closed	-50-50	14	°C
3	OAT_FrostProt	Limit outside air temperature start / frost protection	-50-50	6	°C
4	DAT_LowSetpoint	Discharge air temperature low setpoint	0-50	14	°C
5	DAT_HighSetpoint	Discharge air temperature high setpoint	0-50	26	°C
6	SC_RoomStartComp	Start point outside air temperature summer room temperature compensation	-50-50	20	°C
7	SC_RoomEndComp	End point outside air temperature summer room temperature compensation	-50-50	30	°C
8	SC_RoomSptRaise	Room temperature setpoint raise	0-10	4	K
9	RT_P_band	Room temperature control P-band	0.01-100	50	100/K
10	RT_I_time	Room temperature control I-time	0-1000	0	100/sec
11	RT_ComfortZone	Room temperature comfort zone	0-10	2	K
12	RT_DATSpt_shift	Span for discharge air temperature setpoint shift	0-100	60	%
13	RT_EnergyRecStart	Sequence start point of exchanger	0-100	0	%
14	RT_EnergyRecEnd	Sequence end point of exchanger	0-100	100	%
15	WC_DischStartComp	Start point outside air temperature winter discharge air temperature compensation	-50-50	-10	°C
16	WC_DischEndComp	End point outside air temperature winter discharge air temperature compensation	-50-50	10	°C
17	WC_DischSptRaise	Discharge air temperature setpoint raise	0-10	4	K
18	DAT_P_band	Discharge air temperature control P-band	0.01-100	6.67	100/K
19	DAT_I_time	Discharge air temperature control I-time	0-1000	0.17	100/sec
20	DAT_HeatStart	Sequence start point of heating valve	0-100	0	%
21	DAT_HeatEnd	Sequence end point of heating valve	0-100	50	%
22	DAT_EnergyRecStart	Sequence start point of exchanger	0-100	50	%
23	DAT_EnergyRecEnd	Sequence end point of exchanger	0-100	75	%
24	DAT_CoolStart	Sequence start point of cooling valve	0-100	75	%
25	DAT_CoolEnd	Sequence end point of cooling valve	0-100	100	%
26	DAT_SptRamp	Discharge air temperature setpoint raise	0-20	1	K
27	DAT_SptDecTime	Discharge air temperature control raised setpoint decrease time	0-3600	600	sec
28	HUM_FanStart	Sequence start point of fan speed	0-100	0	%
29	HUM_FanEnd	Sequence end point of fan speed	0-100	100	%
30	DEH_DampersStart	Sequence start point dampers	0-100	0	%
31	DEH_DampersEnd	Sequence end point dampers	0-100	30	%
32	DEH_FanStart	Sequence start point of fan speed	0-100	30	%
33	DEH_FanEnd	Sequence end point of fan speed	0-100	70	%
34	DEH_CoolStart	Sequence start point of cooling valve	0-100	70	%
35	DEH_CoolEnd	Sequence end point of cooling valve	0-100	100	%
36	CO2_P_band	Air quality control P-band	0.01-100	0.5	100/ppm
37	CO2_DampersStart	Sequence start point air quality override dampers	0-100	0	%
38	CO2_DampersEnd	Sequence end point air quality override dampers	0-100	50	%
39	CO2_FanStart	Sequence start point air quality override fan speed	0-100	50	%
40	CO2_FanEnd	Sequence end point air quality override fan speed	0-100	100	%
41	MAD_RecircTimeStart	Period of forced recirculation after start	0-3600	600	sec

Advanced control parameters