Termination Of Ice Build; Return To Non-Ice Build Operations; Attach To Network Device Control; Attaching To Other Ccn Modules - Carrier 19XR Start-Up, Operation And Maintenance Instructions Manual

temperature reset option shall be ignored, if enabled, dur-
ing ice build. The AUTO DEMAND LIMIT INPUT shall
also be ignored if enabled during ice build.
• ECW CONTROL OPTION and any temperature reset
options (configured on TEMP_CTL screen).
• 20 mA DEMAND LIMIT
RAMP_DEM screen).
TERMINATION OF ICE BUILD — The ice build function
terminates under the following conditions:
1. Time Schedule — When the current time on the ice build
time schedule (OCCPC02S) is not set as an ice build time
period.
2. Entering Chilled Water Temperature — Compressor
operation terminates, based on temperature, if the ICE
BUILD TERMINATION parameter is set to 0 (TEMP),
the ENTERING CHILLED WATER temperature is less than
the ICE BUILD SETPOINT, and the ICE BUILD
RECYCLE is set to DSABLE. If the ICE BUILD RE-
CYCLE OPTION is set to ENABLE, a recycle shutdown
occurs and recycle start-up depends on the LEAVING
CHILLED WATER temperature being greater than the
WATER/BRINE CONTROL POINT plus the RECYCLE
RESTART DELTA T temperature.
3. Remote Contacts/Ice Level Input — Compressor opera-
tion terminates when the ICE BUILD TERMINATION
parameter is set to 1 CONTACTS) and the remote con-
tacts are open and the ICE BUILD RECYCLE is set to
DSABLE (0). In this case, the contacts provide ice level
termination control. The contacts are used to stop the
ice build function when a time period on the ice build
schedule (OCCPC02S) is set for ice build operation. The
remote contacts can still be opened and closed to start
and stop the chiller when a specific time period on the ice
build schedule is not set for ice build.
4. Entering Chilled Water Temperature and ICE BUILD Con-
tacts — Compressor operation terminates when the ICE
BUILD TERMINATION parameter is set to 2 (BOTH)
and the conditions described above in items 2 and 3 for
entering chilled water temperature and remote contacts
have occurred.
NOTE: It is not possible to override the CHILLER START/
STOP, CONTROL POINT, and ACTIVE DEMAND LIMIT
variables from CCN devices (with a priority 4 or greater)
during the ice build period. However, a CCN device can over-
ride these settings during 2-chiller lead/lag operation.
RETURN TO NON-ICE BUILD OPERATIONS — The ice
build function forces the chiller to start, even if all other sched-
ules indicate that the chiller should stop. When the ice build
function terminates, the chiller returns to normal tempera-
ture control and start/stop schedule operation. The CHILLER
START/STOP and CONTROL POINT return to normal op-
eration. If the CHILLER START/STOP or CONTROL POINT
has been forced (with a device of less than 4 priority) before
the ice build function started, when the ice build function
ends, the previous forces (of less than 4 priority) are not au-
tomatically restored.

Attach to Network Device Control

menu includes the ATTACH TO NETWORK DEVICE screen.
From this screen, the operator can:
• enter the time schedule number (if changed) for OCCPC03S,
as defined in the NET_OPT screen
• attach the CVC to any CCN device, if the chiller has been
connected to a CCN network. This may include other PIC-
controlled chillers.
• upgrade software
Figure 21 shows the ATTACH TO NETWORK DEVICE
screen. The LOCAL parameter is always the CVC module
OPT (configured on
— The Service
address of the chiller on which it is mounted. Whenever the
controller identification of the CVC changes, the change is
reflected automatically in the BUS and ADDRESS columns
for the local device. See Fig. 16. Default address for local
device is BUS 0 ELEMENT 1.
Fig. 21 — Example of Attach to Network
Device Screen
When the ATTACH TO NETWORK DEVICE screen is
accessed, information can not be read from the CVC on any
device until one of the devices listed on that screen is
attached. The CVC erases information about the module to
which it was attached to make room for information on
another device. Therefore, a CCN module must be attached
when this screen is entered.
To attach any CCN device, highlight it using the
SELECT softkey and press the ATTACH softkey. The mes-
sage ''UPLOADING TABLES, PLEASE WAIT'' displays.
The CVC then uploads the highlighted device or module. If
the module address cannot be found, the message ''COM-
MUNICATION FAILURE'' appears. The CVC then reverts
back to the ATTACH TO DEVICE screen. Try another de-
vice or check the address of the device that would not at-
tach. The upload process time for each CCN module is dif-
ferent. In general, the uploading process takes 1 to 2 minutes.
Before leaving the ATTACH TO NETWORK DEVICE screen,
select the local device. Otherwise, the CVC will be unable
to display information on the local chiller.
ATTACHING TO OTHER CCN MODULES — If the chiller
CVC has been connected to a CCN Network or other PIC
controlled chillers through CCN wiring, the CVC can be used
to view or change parameters on the other controllers. Other
PIC II chillers can be viewed and set points changed (if the
other unit is in CCN control), if desired, from this particular
CVC module.
If the module number is not valid, the ''COMMUNICA-
TION FAILURE'' message will show and a new address num-
ber must be entered or the wiring checked. If the module is
communicating properly, the ''UPLOAD IN PROGRESS''
message will flash and the new module can now be viewed.
Whenever there is a question regarding which module on
the CVC is currently being shown, check the device name
descriptor on the upper left hand corner of the CVC screen.
See Fig. 21.
When the CCN device has been viewed, the ATTACH TO
NETWORK DEVICE table should be used to attach to the
PIC that is on the chiller. Move to the ATTACH TO NET-
WORK DEVICE table (LOCAL should be highlighted) and
press the ATTACH softkey to upload the LOCAL device.
The CVC for the 19XR will be uploaded and default screen
will display.
NOTE: The CVC will not automatically reattach to the local
module on the chiller. Press the ATTACH softkey to attach
to the LOCAL device and view the chiller operation.
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