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72
Table 86 — CCN Configuration
* For units equipped with optional UPC, the CCN Baud Rate must be set to 3.
Accept Global Holidays? (
HOL.T
) — If a device is broad-
casting 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 override occurs when it is initi-
ated. The override may be configured from 1 to 4 hours. If the
time is set to 0, the override function 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 pres-
ent, 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 function 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 abil-
ity 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 override condition as well.
This configuration allows the user to disable the global sched-
ule 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 87.
SPT Low Alert Limit/Occ (
SP.L.O
) — If the space tempera-
ture 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 tempera-
ture 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 tem-
perature 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 tem-
perature 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.
EDT Low Alert Limit/Occ (
SA.L.O
) — If the evaporator dis-
charge temperature is below the configurable occupied
evaporator discharge temperature (EDT) Low Alert Limit
(
SA.L.O
), then Alert 302 will be generated and cooling opera-
tion will be stopped but heating operation will continue. The
alert will automatically reset.
EDT High Alert Limit/Occ (
SA.H.O
) — If the evaporator
discharge temperature is above the configurable occupied EDT
High Alert Limit (
SA.H.O
), then Alert 303 will be generated
and heating operation will be stopped but cooling operation
will continue. The alert will automatically reset.
EDT Low Alert Limit/Unocc (
SA.L.U
) — If the evaporator
discharge temperature is below the configurable unoccupied
EDT Low Alert Limit (
SA.L.U
), then Alert 302 will be gener-
ated and cooling operation will be stopped but heating opera-
tion will continue. The alert will automatically reset.
EDT High Alert Limit/Unocc (
SA.H.U
) — If the evaporator
discharge temperature is above the configurable unoccupied
EDT High Alert Limit (
SA.H.U
), then Alert 303 will be generat-
ed and heating operation will be stopped but cooling operation
will continue. The alert will automatically reset.
RAT Low Alert Limit/Occ (
RA.L.O
) — If the return-air tem-
perature is below the configurable occupied RAT Low Alert
Limit (
RA.L.O
), then Alert 304 will be generated and internal
routines will be modified. Unit operation will continue but
VAV heating operation will be disabled. The alert will automat-
ically reset.
RAT High Alert Limit/Occ (
RA.H.O
) — If the return-air
temperature is above the configurable occupied RAT High
Alert Limit (
RA.H.O
), then Alert 305 will be generated and
operation will continue. The alert will automatically reset.
RAT Low Alert Limit/Unocc (
RA.L.U
) — If the return-air
temperature is below the configurable unoccupied RAT Low
Alert Limit (
RA.L.U
), then Alert 304 will be generated. Unit
operation will continue but VAV heating operation will be dis-
abled. The alert will automatically reset.
RAT High Alert Limit/Unocc (
RA.H.U
) — If the return-air
temperature is above the configurable unoccupied RAT High
Alert Limit (
RA.H.U
), then Alert 305 will be generated. Oper-
ation will continue. The alert will automatically reset.
RARH Low Alert Limit (
R.RH.L
) — If the unit is config-
ured to use a return air relative humidity sensor (
Configura-
tion
UNIT
SENS
RRH.S
), and the measured level is
below the configurable RH Low Alert Limit (
R.RH.L
), then
Alert 308 will occur. The unit will continue to run and the alert
will automatically reset.
RARH High Alert Limit (
R.RH.H
) — If the unit is config-
ured to use a return air relative humidity sensor (
Configura-
tion
UNIT
SENS
RRHS
), and the measured level is
above the configurable RARH High Alert Limit (
R.RH.H
),
ITEM
EXPANSION
RANGE
UNITS
POINT
DEFAULT
CCN
CCN CONFIGURATION
CCNA
CCN Address
1 - 239
CCNADD
1
CCNB
CCN Bus Number
0 - 239
CCNBUS
0
BAUD
CCN Baud Rate
1 - 5
CCNBAUDD
3*
BROD
CCN BROADCST DEFINITIONS
TM.DT
CCN Time/Date Broadcast
ON/OFF
CCNBC
On
OAT.B
CCN OAT Broadcast
ON/OFF
OATBC
Off
ORH.B
CCN OARH Broadcast
ON/OFF
OARHBC
Off
OAQ.B
CCN OAQ Broadcast
ON/OFF
OAQBC
Off
G.S.B
Global Schedule Broadcst
ON/OFF
GSBC
Off
B.ACK
CCN Broadcast Ack'er
ON/OFF
CCNBCACK
Off
SC.OV
CCN SCHEDULES-OVERRIDES
SCH.N
Schedule Number
0 - 99
SCHEDNUM
1
HOL.T
Accept Global Holidays?
YES/NO
HOLIDAYT
No
O.T.L.
Override Time Limit
0 - 4
HRS
OTL
1
OV.EX
Timed Override Hours
0 - 4
HRS
OVR_EXT
0
SPT.O
SPT Override Enabled ?
YES/NO
SPT_OVER
Yes
T58.O
T58 Override Enabled ?
YES/NO
T58_OVER
Yes
GL.OV
Global Sched. Override ?
YES/NO
GLBLOVER
No
Summary of Contents for WEATHERMAKER 48/50AJ
Page 103: ...103 Fig 15 Typical Main Control Box Wiring Schematic 48 50AJ AK AW AY Units cont a48 8355 ...
Page 104: ...104 Fig 16 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units a48 8355 ...
Page 105: ...105 TO NEXT PAGE Fig 17 Typical Auxiliary Control Box Wiring Schematic A48 7294 ...
Page 106: ...106 Fig 17 Typical Auxiliary Control Box Wiring Schematic cont a48 8356 ...
Page 107: ...107 Fig 18 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown a48 8357 ...
Page 113: ...113 Fig 22 Typical Power Schematic 48 50A2 A3 A4 A5060 Unit Shown ...
Page 114: ...114 SW1 SW2 OR DEHUMIDIFY SWITCH Fig 23 Typical Controls Option Wiring Schematic a48 8361 ...
Page 115: ...115 Fig 24 Typical Small Chassis Component Location Size 020 035 Units a48 8362 ...
Page 116: ...116 Fig 25 Typical Large Chassis Component Locations Size 036 060 Units A48 7302 ...
Page 169: ...169 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...