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63
Hydronic Heating Control Proportional Gain (HW.P)
This configuration is the proportional term for the PID, which
runs in the HVAC mode LOW HEAT.
Hydronic Heating Control Integral Gain (HW.I)
This configuration is the integral term for the PID, which runs
in the HVAC mode LOW HEAT.
Hydronic Heating Control Derivative Gain (HW.D)
This configuration is the derivative term for the PID, which
runs in the HVAC mode LOW HEAT.
Hydronic Heating Control Run Time Rate (HW.TM)
This configuration is the PID run time rate, which runs in the
HVAC mode LOW HEAT.
Hydronic Heating Logic
If the HVAC mode is LOW HEAT:
• The control will command the supply fan on.
• The control will modulate the hot water or steam coil actu
-
ator to the heating control point (
Run Status
VIEW
HT.C.P
). The heating control point for hydronic heat is the
heating supply air set point (
Setpoints
SA.HT
).
If the HVAC mode is HIGH HEAT:
• The control will command the supply fan on.
• The control will command the hot water coil actuator to
100%.
Hydronic Heating PID Process
If the HVAC mode is LOW HEAT, then the hydronic heating
actuator will modulate to the heating control point (
Run Sta
-
tus
VIEW
HT.C.P
). Control is performed with a generic
PID loop where:
Error = Heating Control Point (
HT.C.P
) – Leaving Air Tem
-
perature (LAT)
The PID terms are calculated as follows:
P = K *
HW.P
* error
I = K *
HW.I
* error + “I” last time through
D = K *
HW.D
* (error – error last time through)
Where K =
HW.TM
/60 to normalize the effect of changing the
run time rate.
NOTE: The PID values should not be modified without ap
-
proval from Carrier service personnel.
Freeze Status Switch Logic (Inputs
GEN.I
FRZ.S)
If the freezestat input (FRZ) alarms, indicating that the coil is
freezing, normal heat control is overridden and the following
actions will be taken:
1. Command the hot water coil actuator to 100%.
2. Command the economizer damper to 0%.
3. Command the supply fan on.
Table 36 —
Hydronic Heat Configuration
ITEM
EXPANSION
RANGE
UNITS
CCN POINT
DEFAULT
HH.CF
HYDRONIC HEAT CONFIGS
HW.P
Hydronic Ctl.Prop. Gain
0 to 1.5
HW_PGAIN
1
HW.I
Hydronic Ctl.Integ. Gain
0 to 1.5
HW_IGAIN
1
HW.D
Hydronic Ctl.Derv. Gain
0 to 1.5
HW_DGAIN
1
HW.TM
Hydronic PID Rate Config
15 to 300
sec
HOTWPIDR
90
ACT.C
HYDR.HEAT ACTUATOR CFGS.
SN.1.1
Hydronic Ht.Serial Num.1
0 to 9999
HTC1_SN1
0
SN.1.2
Hydronic Ht.Serial Num.2
0 to 6
HTC1_SN2
0
SN.1.3
Hydronic Ht.Serial Num.3
0 to 9999
HTC1_SN3
0
SN.1.4
Hydronic Ht.Serial Num.4
0 to 254
HTC1_SN4
0
C.A.L1
Hydr.Ht.Ctl.Ang Lo Limit
0 to 90
HTC1CALM
0
SN.2.1
Humd/HTC2 Ser Num 1
0 to 9999
HTC2_SN1
0
SN.2.2
Humd/HTC2 Ser Num 2
0 to 6
HTC2_SN2
0
SN.2.3
Humd/HTC2 Ser Num 3
0 to 9999
HTC2_SN3
0
SN.2.4
Humd/HTC2 Ser Num 4
0 to 254
HTC2_SN4
0
C.A.L2
Humd/HTC2 Ctl Ang Lo Lim
0 to 90
HTC2CALM
0
SN.3.1
HTC3 Serial Number 1
0 to 9999
HTC3_SN1
0
SN.3.2
HTC3 Serial Number 2
0 to 6
HTC3_SN2
0
SN.3.3
HTC3 Serial Number 3
0 to 9999
HTC3_SN3
0
SN.3.4
HTC3 Serial Number 4
0 to 254
HTC3_SN4
0
C.A.L3
HTC3 Ctrl Angle Lo Limit
0 to 90
HTC3CALM
0
SN.4.1
HTC4 Serial Number 1
0 to 9999
HTC4_SN1
0
SN.4.2
HTC4 Serial Number 2
0 to 6
HTC4_SN2
0
SN.4.3
HTC4 Serial Number 3
0 to 9999
HTC4_SN3
0
SN.4.4
HTC4 Serial Number 4
0 to 254
HTC4_SN4
0
C.A.L4
HTC4 Ctrl Angle Lo Limit
0 to 90
HTC4CALM
0
Summary of Contents for WeatherExpert 48N2
Page 135: ...135 Fig 18 48 50N Typical Power Schematic Nominal 075 Ton Unit Shown ...
Page 136: ...136 Fig 19 48 50N Typical Power Schematic Nominal Ton 90 150 Units Shown ...
Page 137: ...137 Fig 20 48 50N Main Base Board Input Output Connections ...
Page 138: ...138 Fig 21 48 50N RXB EXB CEM Input Output Connections a48 9307 ...
Page 139: ...139 Fig 22 48 50N EXV SCB Input Output Connections a48 9308 ...
Page 140: ...140 Fig 23 48N Typical Modulating Gas Heat Unit Control Wiring ...
Page 141: ...141 Fig 24 50N Typical Electric Heat Unit Control Wiring ...
Page 144: ...144 Fig 27 48N Typical Gas Heat Section Wiring Nominal Ton 120 to 150 Units ...
Page 145: ...145 Fig 28 48 50N Typical Power Component Control Wiring 460 v ...
Page 146: ...146 Fig 29 48 50N Component Control Wiring 575 v Nominal Ton 075 to 150 Units ...
Page 147: ...147 Fig 30 48 50N Component Arrangement Power Box ...
Page 148: ...148 Fig 31 48 50N Component Arrangement Control Box ...
Page 240: ...240 APPENDIX D VFD INFORMATION CONT Fig G VFD Bypass Wiring Diagram WHEN USED ...