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tion set to ON. If more than one time broadcaster is present,
problems with the time will occur.
NOTE: Only the time and date broadcaster can perform day
-
light savings time adjustments. Even if the rooftop is stand-
alone, the user may want to set this to ON to accomplish the
daylight/savings function.
CCN OAT Broadcast (OAT.B)
If this configuration is set to ON, the control will periodically
broadcast its outside-air temperature at a rate of once every 30
minutes.
CCN OARH Broadcast (ORH.B)
If this configuration is set to ON, the control will periodically
broadcast its outside air relative humidity at a rate of once ev
-
ery 30 minutes.
CCN OAQ Broadcast (OAQ.B)
If this configuration is set to ON, the control will periodically
broadcast its outside air quality reading at a rate of once every
30 minutes.
Global Schedule Broadcast (G.S.B)
If this configuration is set to ON and the schedule number
(
SCH.N
) is between 65 and 99, then the control will broadcast
the internal time schedule once every 2 minutes.
CCN Broadcast Acknowledger (B.ACK)
If this configuration is set to ON, then when any broadcasting
is done on the bus, this device will respond and acknowledge.
Only one device per bus can be configured for this option.
Schedule Number (SCH.N)
This configuration determines what schedule the control may
follow.
SCH.N
= 0
The control is always occupied.
SCH.N
= 1
The control follows its internal time schedules.
The user may enter any number between 1 and
64, but it will be overwritten to “1” by the con
-
trol, as it only has one internal schedule.
SCH.N
= 65-99 The control is either set up to receive to a
broadcasted time schedule set to this number,
or the control is set up to broadcast its internal
time schedule (
G.S.B
) to the network, and this
is the global schedule number it is broadcast
-
ing. If this is the case, then the control still fol
-
lows its internal time schedules.
Accept Global Holidays? (HOL.T)
If a device is broadcasting the time on the bus, it is possible to
accept the time, yet not accept the global holiday from the
broadcast message.
Override Time Limit (O.T.L)
This configuration allows the user to decide how long an over
-
ride occurs when it is initiated. The override may be config
-
ured from 1 to 4 hours. If the time is set to 0, the override func
-
tion will become disabled.
Timed Override Hours (OV.EX)
This displays the current number of hours left in an override. It
is possible to cancel an override in progress by writing “0” to
this variable, thereby removing the override time left.
SPT Override Enabled? (SPT.O)
If a space sensor is present, then it is possible to override an
unoccupied period by pushing the override button on the T55
or T56 sensor. This option allows the user to disable this func
-
tion by setting this configuration to NO.
T58 Override Enabled? (T58.O)
The T58 sensor is a CCN device that allows cooling/heating set
points to be adjusted, space temperature to be written to the
rooftop unit, and the ability to initiate a timed override. This
option allows the user to disable the override initiated from the
T58 sensor by setting this option to NO.
Global Schedule Override? (GL.OV)
If the control is set to receive global schedules, then it is also
possible for the global schedule broadcaster to call out an over
-
ride condition, as well. This configuration allows the user to dis
-
able the global schedule broadcaster from overriding the control.
Alert Limit Configuration
The ALLM submenu is used to configure the alert limit set
points. A list is shown in Table 62.
SPT Low Alert Limit/Occ (SP.L.O)
If the space temperature is below the configurable occupied SPT
Low Alert Limit (
SP.L.O
), then Alert 300 will be generated and
the unit will be stopped. The alert will automatically reset.
SPT High Alert Limit/Occ (SP.H.O)
If the space temperature is above the configurable occupied SPT
High Alert Limit (
SP.H.O
), then Alert 301 will be generated and
the unit will be stopped. The alert will automatically reset.
SPT Low Alert Limit/Unocc (SP.L.U)
If the space temperature is below the configurable unoccupied
SPT Low Alert Limit (
SP.L.U
), then Alert 300 will be generated
and the unit will be stopped. The alert will automatically reset.
SPT High Alert Limit/Unocc (SP.H.U)
If the space temperature is above the configurable unoccupied
SPT High Alert Limit (
SP.H.U
), then Alert 301 will be generated
and the unit will be stopped. The alert will automatically reset.
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 ...