APC ACRC500 Installation Manual download pdf (Page 21)

13InRow RC Operation and Maintenance

%Glycol. The percentage of glycol used by the Cooling Group to cool the environment. Only qualified

service personnel should make changes to this setting.

Fan Cntrl. This selection allows air flow to be controlled automatically by the cooling unit or maually

by user-selected fan speed preference.

• Auto: Air flow is automatically controlled by the cooling unit.

• Manual: The air flow is fixed to the value of the Fan Speed Preference property. See page 15 for

more information

Availability. Redundancy, Runtime Balancing and Assist modes are only supported in HACS and

RACS configurations.

• Backup Units: The cooling unit is not running but is ready to run if a unit fails, is unable to cool

or needs cooling assistance.

• Load Asst (Load Assist): The unit was previously in the Backup mode but is now running due to

a request for cooling assistance. When the assistance is no longer needed, the unit will return to

the Backup state. If a failure occurs on a cooling unit while the backup unit is assisting, the

backup unit will take over for the failed cooling unit.

• Runtm Bal (Runtime Balancing): The system will maintain similar runtimes between units in

the group. When the difference between the runtime hours of the cooling units in the system

exceeds 72 hours, the system will automatically exchange modes between the longest running

Primary cooling unit and the Backup with the least Runtime hours.

Note: The Runtime Balancing cap is not adjustable.

Runtime hours are hours that the cooling unit is actually operating and NOT 72

consecutive hours (3 days) of time.

Identify the cooling unit

Path: Main > Set Identification

The Set Identification menu contains settings that identify the name and location of the cooling unit.

Unit Id. Assign a unique identification number to this cooling unit. Range: 1 through 12.

Name. Assign a Name, up to 40 alpha-numeric characters, to the cooling unit..

Location. Enter the Location, up to 40 alpha-numeric characters, of the cooling unit..

Note: Only the first 19 characters (of the 40 that are possible to enter) will display on the

display interface. You must use Telnet, the Control console or the Web to access all 40

characters. See page 30 and page 31 for more information.

Configure Modbus

Path: Main > Configure Modbus

Use the Configure Modbus menu to set up communications between the cooling unit and the building

management system.

Modbus. Enable or disable Modbus communication protocol.

Target Id. Each Modbus device must have a unique target identification number. Enter a unique number

for this cooling unit.

Baud Rate. Set either 9600 bps or 19200 bps.

Fixed settings: 8 data bits, no parity, 1 stop bit. These settings cannot be modified.

1 2 ... 16 17 18 19 20 21 22 23 24 25 26 ... 47 48

No comments

APC ACRC500 Installation Manual Page 21