48/50PG and PM
Global Schedule Broadcast (BROD"B.GS)
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 (BROD"B.ACK)
If this configuration is set to ON, then when any broadcasting is done on the bus, this device will respond to and acknowledge. Only one device per bus can be configured for this option.
Schedule Number (SCH.O"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 control as it only |
| has one internal schedule. |
SCH.N = | The control is either set up to |
| receive to a broadcasted time |
| schedule set to this number or |
| the control is set up to broad |
| cast its internal time schedule |
| (B.GS) to the network and this is |
| the global schedule number it is |
| broadcasting. If this is the case, |
| then the control still follows its |
| internal time schedules. |
Accept Global Holidays? (SCH.O"HOL.G)
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 (SCH.O"OV.TL)
This configuration allows the user to decide how long an override occurs when it is initiated. 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 (SCH.O"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? (SCH.O"OV.SP)
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 function by setting this configuration to NO.
Demand Limit
Demand Limit Control may override the cooling algorithm to limit or reduce cooling capacity during run time. The term Demand Limit Control refers to the restriction of machine capacity to control the amount of power that a machine will use. This can save the owner money by limiting peaks in the power supply. Demand limit control is intended to interface with an external network system. This is through a CCN Loadshed POC Device or writing to network points.
To limit stages through network writes, the points Run Status →COOL→MAX.C and Run Status→HEAT→MAX.H are forced on the network through CCN points MAXCSTGS and MAXHSTGS respectively. Force these to the desired maximum stages of cooling/dehumidification and heating, respectively. When there is no force on these points, they automatically reset to allow all cooling/dehumidification and heating stages to be used. These points are reset at power−on/reset (POR).
When using the Loadshed POC to do Demand Limiting, the cool and heat stage limits under both Redline and Loadshed conditions can be set individually with configuration decisions. If the active stages is greater then the loadshed or redline configurations when a loadshed or redline command is given, the unit will remove stages.
Configuration→CCN→LDSH→S.GRP
This is the Loadshed Group Number and corresponds to the loadshed supervisory devices that resides elsewhere on the CCN network and broadcasts loadshed and redline commands to its associated equipment parts. This variable will default to zero which is an invalid group number. This allows the loadshed function to be disabled until configured.
Configuration→CCN→LDSH→R.MXC
This configuration tells the unit the maximum cooling stages allowed to be on during a redline condition.
Configuration→CCN→LDSH→S.MXC
This configuration tells the unit the maximum cooling stages allowed to be on during a loadshed condition.
Configuration→CCN→LDSH→R.MXH
This configuration tells the unit the maximum heating stages allowed to be on during a redline condition.
Configuration→CCN→LDSH→S.MXH
This configuration tells the unit the maximum heating stages allowed to be on during a loadshed condition.
The two Demand Limiting methods can be active simultaneously. The lowest cool and heat stage limits imposed by either method are applied, and these ”effective stage limits” are shown in the points CSTGLIMT (Run Status→COOL→LMT.C) and HSTGLIMT (Run Status→HEAT→LMT.H), respectively. In normal running mode, these limits will prevent stages from being added, or stages to be removed, as applicable. In test mode, these limits are ignored, and the user may continue to operate all stages. The point MODEDMDL (Run Status→MODE→D.LMT) is used to show if any Demand Limiting is in effect that prevents the unit from operating either cooling or heating at full−capacity.
NOTE: MODEDMDL may reflect that staging is NOT limited even though Loadshed is active, or the network points are being forced, if the stage limits in effect are not less than the stages present in the unit.
If a more drastic mode of Demand Limiting is required, the network point HVACDOWN (Run Status→MODE→HV.DN) can be used to prohibit the unit from selecting any HVAC mode, thus preventing the operation of the supply fan, compressors, condenser fans, and heat stages. This point must also be forced, and is reset automatically when not forced, and at POR.
NOTE: HVACDOWN can be used as an immediate shutdown of the unit before limiting capacity (ex. Generator switching).
Linkage
ComfortLinkt controls do not require any configuration settings to establish linkage with a Linkage Coordinator. This is done automatically when the unit’s bus and element address are configured in the Linkage Coordinator’s LINKAGE configuration table. The linkage information that is supplied to the ComfortLink unit by the Linkage Coordinator is as follows:
SReference zone temperature
SReference zone occupied biased heating and cooling set points
SReference zone unoccupied heating and cooling set points
SComposite occupancy mode
The unit will control the equipment based on this information and in return will provide the Linkage Coordinator with the following data:
SOperating mode − Cooling, Heating, Free Cooling, Fire Shutdown Evacuation, or Off
SSupply−air temperature
SOptimal Start Bias time (Based on worst case zone)
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