Carrier 19XR, XRV specifications Example of Attach to Network Device Screen

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 Contacts — 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) dur- ing the ice build period. However, a CCN device can override 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 temperature control and start/stop schedule operation. The CHILLER START/STOP and CONTROL POINT return to normal opera- tion. 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 automatically restored.

Attach to Network Device Control — The Service 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/ICVC to any CCN device, if the chiller has been connected to a CCN network. This may include other PIC-controlled chillers.

•upgrade software

Figure 24 shows the ATTACH TO NETWORK DEVICE screen. The LOCAL parameter is always the CVC/ICVC mod- ule address of the chiller on which it is mounted. Whenever the controller identification of the CVC/ICVC changes, the change is reflected automatically in the BUS and ADDRESS columns for the local device. See Fig. 18. Default address for local de- vice is BUS 0 ADDRESS 1.

When the ATTACH TO NETWORK DEVICE screen is ac- cessed, information can not be read from the CVC/ICVC on any device until one of the devices listed on that screen is at- tached. The CVC/ICVC erases information about the module to which it was attached to make room for information on an- other 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 message “UP- LOADING TABLES, PLEASE WAIT” displays. The CVC/ ICVC then uploads the highlighted device or module. If the

Fig. 24 — Example of Attach to Network

Device Screen

module address cannot be found, the message “COMMUNI- CATION FAILURE” appears. The CVC/ICVC then reverts back to the ATTACH TO DEVICE screen. Try another device or check the address of the device that would not attach. The upload process time for each CCN module is different. In gen- eral, the uploading process takes 1 to 2 minutes. Before leaving the ATTACH TO NETWORK DEVICE screen, select the lo- cal device. Otherwise, the CVC/ICVC will be unable to display information on the local chiller.

ATTACHING TO OTHER CCN MODULES — If the chill- er CVC/ICVC has been connected to a CCN Network or other PIC controlled chillers through CCN wiring, the CVC/ICVC can be used to view or change parameters on the other control- lers. Other PIC II chillers can be viewed and set points changed (if the other unit is in CCN control), if desired, from this partic- ular CVC/ICVC 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/ICVC is currently being shown, check the device name descriptor on the upper left hand corner of the CVC/ ICVC screen. See Fig. 24.

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 NETWORK DEVICE table (LOCAL should be highlighted) and press the ATTACH softkey to upload the LOCAL device. The CVC/ ICVC for the 19XR will be uploaded and default screen will display.

NOTE: The CVC/ICVC 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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