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alert. When the rooftop loses its link, the temperature and set
points are derived locally. Recovery is automatic on re-establish
-
ment of communications. Reason for failure may be wiring er
-
ror, too much bus activity, or damaged RS-485 drivers.
T210 (Building Pressure Transducer Failure)
If the building pressure transducer (
Pressures
AIR.P
BP
)
fails, building pressure control fails also. Recovery is automat
-
ic. Reason for error is either a faulty sensor, wiring error, or
damaged input on the RXB control board.
T211 (Static Pressure Transducer Failure)
If the static pressure transducer (
Pressures
AIR.P
SP
) fails,
static pressure control fails also. Recovery is automatic. Rea
-
son for error is either a faulty sensor, wiring error, or damaged
input on the RXB control board.
T220 (Indoor Air Quality Sensor Failure)
If the indoor air quality sensor (
Inputs
AIR.Q
IAQ
) fails,
demand controlled ventilation is not possible. The control de
-
faults to the max vent position. Recovery is automatic. Reason
for error is either a faulty sensor, wiring error, or damaged in
-
put on the MBB control board.
T221 (Outdoor Air Quality Sensor Failure)
If the outdoor air quality sensor (
Inputs
AIR.Q
OAQ
) fails,
OAQ defaults to 400 ppm and demand controlled ventilation
will continue. Recovery is automatic. Reason for error is either
a faulty sensor, wiring error, or damaged input on the CEM
control board.
T229 (Economizer Min Pos Override Input Failure)
If the economizer minimum position override input fails, the
economizer will operate as if it were not configured for override.
Recovery is automatic. Reason for error is either a faulty sensor,
wiring error, or damaged input on the MBB control board. This
error only occurs when the unit is configured for minimum posi
-
tion override and a 4 to 20 mA signal is not present.
T245 (Outside Air CFM Sensor Failure)
If the outside air cfm sensor (
Inputs
CFM
O.CFM
) fails,
the economizer will default to discrete positioning of the econ
-
omizer (
Configuration
IAQ
DCV.C
IAQ.M
,
Configura
-
tion
ECON
EC.MN
). Recovery is automatic. Reason for
error is either a faulty sensor, wiring error, or damaged input on
the CEM control board.
T246 (Supply Air CFM Sensor Failure)
If the supply air cfm sensor (
Inputs
CFM
S.CFM
) fails,
fan tracking is not possible and the system will shut down. Re
-
covery is automatic. Reason for error is either a faulty sensor,
wiring error, or damaged input on the EXB control board.
T247 (Return Air CFM Sensor Failure)
If the return air cfm sensor (
Inputs
CFM
R.CFM
) fails, fan
tracking is not possible and the system will shut down. Recov
-
ery is automatic. Reason for error is either a faulty sensor, wir
-
ing error, or damaged input on the EXB control board.
T248 (Exhaust Air CFM Sensor Failure)
If the exhaust air cfm sensor (
Inputs
CFM
E.CFM
) fails,
exhaust air cfm will not be properly reported. Recovery is au
-
tomatic. Reason for error is either a faulty sensor, wiring error,
or damaged input on the EXB control board.
T300 (Space Temperature Below Limit)
If the space temperature is below the configurable SPT Low Alert
Limits (occupied [
Configuration
IAQ
ALLM
SP.L.O
] for 5
minutes or unoccupied [
Configuration
IAQ
ALLM
SP.L.U
]
for 10 minutes), then an alert will be broadcast. The alert will au
-
tomatically reset.
T301 (Space Temperature Above Limit)
If the space temperature is above the configurable SPT High Alert
Limits (occupied [
Configuration
IAQ
ALLM
SP.H.O
] for
5 minutes or unoccupied [
Configuration
IAQ
ALLM
SP.H.U
] for 10 minutes), then an alert will be broadcast. The alert
will automatically reset.
T302 (Supply Temperature Below Limit)
If the supply-air temperature measured by the supply tempera
-
ture sensor is below the configurable SAT LO Alert Limit/Occ
(
Configuration
IAQ
ALLM
SA.L.O
) for 5 minutes or the
Low Supply air temperature alert limit unoccupied mode (
Con
-
figuration
IAQ
ALLM
SA.L.U
) for 10 minutes, then an
alert will be broadcast.
T303 (Supply Temperature Above Limit)
If the supply temperature is above the configurable SAT HI
Alert Limit Occ (
Configuration
IAQ
ALLM
SAH.O
) for
5 minutes or the SAT HI Alert Limit/Unocc (
Configura
-
tion
IAQ
ALLM
SA.H.U
) for 10 minutes, then an alert
will be broadcast. The alert will automatically reset.
T304 (Return Temperature Below Limit)
If the return air temperature measured by the RAT sensor is be
-
low the configurable RAT LO Alert Limit/Occ (
Configura
-
tion
IAQ
ALLM
RA.L.O
) for 5 minutes or RAT HI Alert
Limit/Occ (
Configuration
IAQ
ALLM
RA.L.U
) for
10 minutes, then an alert will be broadcast.
T305 (Return Temperature Above Limit)
If the return air temperature is below the RAT HI Alert Limit/Occ
(
Configuration
IAQ
ALLM
RA.H.O
) for 5 minutes or RAT
HI Alert Limit/Occ (
Configuration
IAQ
ALLM
RA.H.U
)
for 10 minutes, then an alert will be broadcast. The alert will auto
-
matically reset.
T308 (Return Air Relative Humidity Below Limit)
If the unit is configured to use a return air relative humidity
sensor through the Return Air RH Sensor (
Configura
-
tion
UNIT
SENS
RRH.S
) setting, and the measured lev
-
el is below the configurable RH Low Alert Limit (
Configura
-
tion
IAQ
ALLM
R.RH.L
) for 5 minutes, then the alert
will occur. The unit will continue to run and the alert will auto
-
matically reset.
T309 (Return Air Relative Humidity Above Limit)
If the unit is configured to use a return air relative humidity sensor
through the Return Air RH Sensor (
Configuration
UNIT
SENS
RRH.S
) setting, and the measured level is above the con
-
figurable RH High Alert Limit (
Configuration
IAQ
ALLM
R.RH.H
) for 5 minutes, then the alert will occur.
Unit will continue to run and the alert will automatically reset.
T310 (Supply Duct Static Pressure Below Limit)
If the unit is a VAV unit with a supply duct pressure sensor and
the measured supply duct static pressure (
Pres
-
sures
AIR.P
SP
) is below the configurable SP Low Alert
Limit (
Configuration
IAQ
ALLM
SP.L
) for 5 minutes,
then the alert will occur. The unit will continue to run and the
alert will automatically reset.
T311 (Supply Duct Static Pressure Above Limit)
If the unit is a VAV unit with a supply duct pressure sensor and
measured supply duct static pressure (
Pressures
AIR.P
SP
)
is above the configurable SP Low Alert Limit (
Configura
-
tion
IAQ
ALLM
SP.H
) for 5 minutes, then the alert will
occur. The unit will continue to run and the alert will automati
-
cally reset.
T312 (Building Static Pressure Below Limit)
If the unit is configured to use modulating power exhaust, then
a building static pressure limit can be configured using the BP
Low Alert Limit (
Configuration
IAQ
ALLM
BP.L
). If
the measured pressure (
Pressures
AIR.P
BP
) is below the
limit for 5 minutes then the alert will occur.
T313 (Building Static Pressure Above Limit)
If the unit is configured to use modulating power exhaust, then
a building static pressure limit can be configured using the BP
HI Alert Limit (
Configuration
IAQ
ALLM
BP.H
). If the
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 ...