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98
Forcing Inputs and Outputs
Many variables may be forced both from the CCN and directly
at the local display. This can be useful during diagnostic testing
and also during operation, typically as part of an advanced
third party control scheme. See Appendices A and B.
NOTE: In the case of a power reset, any force in effect at the time
of the power reset will be cleared.
CONTROL LEVEL FORCING
If any of the following points are forced with a priority level of
7 (consult CCN literature for a description of priority levels),
the software clears the force from the point if it has not been
written to or forced again within the timeout periods defined
below:
Run Status Menu
The Run Status menu provides the user important information
about the unit. The Run Status table can be used to trouble-
shoot problems and to help determine how and why the unit is
operating.
AUTO VIEW OF RUN STATUS
The Auto View of Run Status display table provides the most
important unit information. The HVAC Mode (
Run Status
VIEW
HVAC
) informs the user what HVAC mode the unit
is currently in. Refer to the Modes section on page 27 for infor-
mation on HVAC modes. The occupied status, unit tempera-
tures, unit setpoints, and stage information can also be shown.
See Table 90.
Run Status
VIEW
HVAC
Displays the current HVAC Mode(s) by name. HVAC Modes
include:
Run Status
VIEW
OCC
This variable displays the current occupancy status of the control.
Run Status
VIEW
MAT
This variable displays the current value for mixed-air tempera-
ture. This value is calculated based on return-air and outside-
air temperatures and economizer damper position.
Run Status
VIEW
EDT
This variable displays the current evaporator discharge air tem-
perature during Cooling modes. This value is read at the supply
air thermistor location (or at cooling coil thermistor array if
unit is equipped with hydronic heating coil).
Run Status
VIEW
LAT
This variable displays the current leaving-air temperature
during Vent and Hydronic Heating modes. This value is read at
the supply air thermistor location.
Run Status
VIEW
EC.C.P
This variable displays the current economizer control point
value (a target value for air temperature leaving the evaporator
coil location).
Run Status
VIEW
ECN.P
This variable displays the current actual economizer position
(in percentage open).
Run Status
VIEW
CL.C.P
This variable displays the current cooling control point (a target
value for air temperature leaving the evaporator coil location).
Run Status
VIEW
C.CAP
This variable displays the current amount of unit cooling ca-
pacity (in percent of maximum).
Run Status
VIEW
HT.C.P
This variable displays the current heating control point, for use
with staged gas control option only (a target value for air tem-
perature leaving the supply duct).
Run Status
VIEW
HT.ST
This variable displays the current number of heating stages ac-
tive (for staged gas control option only). Compare to following
point.
Run Status
VIEW
H.MAX
This variable displays the maximum number of heat stages
available for this model.
ECONOMIZER RUN STATUS
The Economizer Run Status display table provides information
about the economizer and can be used to troubleshoot econo-
mizer problems. See Table 91. The current position, command-
ed position, and whether the economizer is active can be dis-
played. All the disabling conditions for the economizer and
outside air information is also displayed.
COOLING INFORMATION
The Cooling Information run status display table provides in-
formation on the cooling operation and the Humidi-MiZer op-
eration of the unit. See Table 92.
Current Running Capacity (C.CAP)
This variable represents the amount of capacity currently run-
ning as a percent.
Current Cool Stage (CUR.S)
This variable represents the cool stage currently running.
Maximum Cool Stages (MAX.S)
This variable is the maximum number of cooling stages the
control is configured for and capable of controlling.
Active Demand Limit (DEM.L)
If demand limit is active, this variable will represent the
amount of capacity that the control is currently limited to.
Capacity Load Factor (SMZ)
This factor builds up or down over time (–100 to +100) and is
used as the means of adding or subtracting a cooling stage
during run time. It is a normalized representation of the rela-
tionship between “Sum” and “Z”. See the SUMZ Cooling Al-
gorithm section on page 42.
Temperatures
AIR.T
OAT
Outside Air Temperature
30 minutes
Temperatures
AIR.T
RAT
Return Air Temperature
3 minutes
Temperatures
AIR.T
SPT
Space Temperature
3 minutes
Inputs
RSET
SP.RS
Static Pressure Reset
30 minutes
Inputs
REL.H
OA.RH
Outside Air Relative Humidity 30 minutes
Inputs
AIR.Q
OAQ
Outside Air Quality
30 minutes
OFF
LOW COOL
SMOKE PURGE
VENT
PRESSURIZATION
REM SW DISABLE
HIGH HEAT
DISABLED
TEMPERING LOCOOL
STARTING UP
UNOCC FREE COOL
COMP STUCK ON
HIGH COOL
EVACUATION
TEMPERING VENT
FIRE SHUT DOWN
SOFTSTOP REQUEST
TEST
SHUTTING DOWN
TEMPERING HICOOL
LOW HEAT
Summary of Contents for WEATHERMAKER 48A2020
Page 112: ...112 Fig 20 Typical Main Control Box Wiring Schematic 48 50A Units ...
Page 113: ...113 Fig 21 Typical Auxiliary Control Box Wiring Schematic ...
Page 114: ...114 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown ...
Page 115: ...115 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown TO NEXT PAGE ...
Page 116: ...116 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont ...
Page 117: ...117 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown ...
Page 118: ...118 Fig 25 Typical Controls Option Wiring Schematic SW1 SW2 OR DEHUMIDIFY SWITCH ...
Page 119: ...119 Fig 26 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown ...
Page 120: ...120 Fig 27 Typical Power Schematic of Greenspeed Low Ambient Option 48 50A 060 Unit Shown ...
Page 121: ...121 Fig 28 Typical Small Chassis Component Location Size 020 035 Units ...
Page 122: ...122 Fig 29 Typical Large Chassis Component Locations Size 040 060 Units ...
Page 185: ...185 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...