80
Table 65 — Economizer Run Status Table
Economizer Control Point Determination Logic
Once the economizer is allowed to provide free cooling, the
economizer must determine exactly what set point it should try
to maintain. The set point the economizer attempts to maintain
when “free cooling” is located at
Run Status
VIEW
EC.C.P
. This is the economizer control point.
The control selects set points differently, based on the control
type of the unit. This control type can be found at
Configura-
tion
UNIT
C.TYP
. There are 4 types of control.
C.TYP
= 1 VAV-RAT
C.TYP
= 2 VAV-SPT
C.TYP
= 3 TSTAT Multi-Staging
C.TYP
= 4 SPT Multi-Staging
If the economizer is not allowed to do free cooling, then
EC.C.P
= 0.
If the economizer is allowed to do free cooling and the Unoc-
cupied Free Cooling Mode is ON, then
EC.C.P
= Setpoints
SASP
+
Inputs
RSET
SA.S.R
.
If the economizer is allowed to do free cooling and the Dehu-
midification mode is ON, then
EC.C.P
= the Cooling Control
Point (
Run Status
VIEW
CL.C.P
).
NOTE: To check the current cooling stage, go to
Run Status
COOL
CUR.S
.
If the
C.TYP
is either 1, 2, 3, or 4, and the unit is in a cool
mode, then
EC.C.P
= the Cooling Control Point (
Run Status
VIEW
CL.C.P
).
Building Pressure Control
This control sequence provides control of the building pressure
through the modulating flow rate functions of one of the modu-
lating power exhaust options or through management of the re-
turn fan option. This function also provides control of the con-
stant volume 2-stage power exhaust option.
See below for available power exhaust options for each unit
model.
LEGEND
* Sizes 075-100 only.
† Factory-installed option only.
BUILDING PRESSURE CONFIGURATION
The building pressure configurations are found at the local dis-
play under
Configuration
BP
.
See Table 66.
Building Pressure Config (BP.CF)
This configuration selects the type of building pressure control.
•
BP.CF
= 0, No building pressure control
•
BP.CF
= 1, constant volume two-stage exhaust based on
economizer position
•
BP.CF
= 2, Modulating building pressure control based on
building pressure sensor
•
BP.CF
= 3, VFD controlling two exhaust fan motors
•
BP.CF
= 4, VFD control of one of the two exhaust fan mo-
tors (sizes 075-100 with high-capacity exhaust option)
•
BP.CF
= 5, used on sizes 075-100 with return fan option
Building Pressure Sensor (BP.S)
This configuration allows the reading of a building pressure
sensor when enabled. This is automatically enabled when
BP.CF
= 2, 3, 4, or 5.
Building Pressure (±) Range (BP.R)
This configuration establishes the range in in. wg that a 4 to
20 mA sensor will be scaled to. The control only allows sen-
sors that measure both positive and negative pressure.
ITEM
EXPANSION
RANGE
UNITS
CCN POINT
WRITE STATUS
ECN.P
Economizer Act.Curr.Pos.
0 to 100
%
ECONOPOS
EC2.P
Economzr 2 Act.Curr.Pos.
0 to 100
%
ECON2POS
ECN.C
Economizer Act.Cmd.Pos.
0 to 100
%
ECONOCMD
forcible
ACTV
Economizer Active ?
YES/NO
ECACTIVE
DISA
ECON DISABLING CONDITIONS
UNV.1
Econ Act. Unavailable?
YES/NO
ECONUNAV
UNV.2
Econ2 Act. Unavailable?
YES/NO
ECN2UNAV
ENTH
Enth. Switch Read High ?
YES/NO
ENTH
DBC
DBC - OAT Lockout?
YES/NO
DBC_STAT
DEW
DEW - OA Dewpt.Lockout?
YES/NO
DEW_STAT
DDBC
DDBD- OAT > RAT Lockout?
YES/NO
DDBCSTAT
OAEC
OAEC- OA Enth Lockout?
YES/NO
OAECSTAT
DEC
DEC - Diff.Enth.Lockout?
YES/NO
DEC_STAT
EDT
EDT Sensor Bad?
YES/NO
EDT_STAT
OAT
OAT Sensor Bad ?
YES/NO
OAT_STAT
FORC
Economizer Forced ?
YES/NO
ECONFORC
SFON
Supply Fan Not On 30s ?
YES/NO
SFONSTAT
CLOF
Cool Mode Not In Effect?
YES/NO
COOL_OFF
OAQL
OAQ Lockout in Effect ?
YES/NO
OAQLOCKD
HELD
Econ Recovery Hold Off?
YES/NO
ECONHELD
DH.DS
Dehumid. Disabled Econ.?
YES/NO
DHDISABL
O.AIR
OUTSIDE AIR INFORMATION
OAT
Outside Air Temperature
dF
OAT
forcible
OA.RH
Outside Air Rel. Humidity
%
OARH
forcible
OA.E
Outside Air Enthalpy
OAE
OA.D.T
Outside Air Dewpoint Temp
dF
OADEWTMP
UNIT
CONSTANT
VOLUME
2-STAGE
MODULATING
POWER
EXHAUST
S.O.
VFD*
HIGH
CAPACITY
POWER
EXHAUST†
RETURN/
EXHAUST†
48/50P2,P4
X
X
S.O.
X*
X*
48/50P3,P5
NA
X
S.O.
X*
X*
X
—
Available as Factory Option
S.O.
—
Available as Special Order
NA
—
Not Available on this Unit
VFD
—
Variable Frequency Drive
Summary of Contents for Weathermaster 48P2030-100
Page 130: ...130 Fig 19 Typical Power Schematic Sizes 040 075 Shown ...
Page 131: ...131 Fig 20 Main Base Board Input Output Connections ...
Page 132: ...132 Fig 21 RXB EXB CEM SCB Input Output Connections ...
Page 133: ...133 Fig 22 Typical Gas Heat Unit Control Wiring 48P030 100 Units Shown ...
Page 134: ...134 Fig 23 Typical Electric Heat Wiring 50P030 100 Units Shown ...
Page 135: ...135 Fig 24 Typical Power Wiring 115 V ...
Page 136: ...136 Fig 25 Typical Gas Heat Section Size 030 050 Units Shown ...
Page 138: ...138 Fig 27 Component Arrangement Size 030 035 Units ...
Page 139: ...139 Fig 28 Component Arrangement Size 040 075 Units ...
Page 140: ...140 Fig 29 Component Arrangement Size 090 100 Units ...