APC ACRC500 Manuel d'installation télécharger pdf (Page 23)

15InRow RC Operation and Maintenance

Setpoints

Path: Main > Set Group Setpoints

A setpoint is the target value that a cooling group tries to maintain in the rack. The default setpoints are

appropriate for most cooling applications.

The setpoints for each mode must be within the following ranges:

• Cool: 18.0–25.0°C (64.4–77.0°F)

• Supply Air: 17.0–23.0°C (62.6–73.4°F)

Note: The Supply Air setting is defined when the cooling group is commissioned. This

task is performed by APC authorized personnel only.

Note: If the Supply Air setpoint is greater than the Cool setpoint, the cooling unit

triggers an alarm and resets the Supply Air setpoint to equal the Cool setpoint.

• Fan Spd: Set the fan speed preference that will give you the desired temperature difference (DT).

Each fan speed provides an approximate DT between the supply air from the equipment and the

air returned from the rack.

– Low = 16.7°C (30°F) DT

– Med-Low = 13.9°C (25°F) DT

– Med = 11.1°C (20°F) DT

– Med-High = 6.3°C (15°F) DT

– High = 5.6°C (10°F) DT

Note: The cooling group will automatically override this fan speed setting and adjust

the fan speed to provide optimum cooling for the environment as needed.

PID settings

Path: Main > Set Group PIDs

The Proportional plus Integral plus Derivative (PID) loop controls the output of the fans.

Caution: This procedure is to be performed by APC authorized personnel only. Improperly

set PID controls could result in equipment damage.

Gain (P). The proportional multiplier (gain) for this mode or actuator. The proportional multiplier

adjusts for the difference (error) between the measured value and the setpoint.

Rate (I). The integral multiplier (reset rate) for this mode or actuator. The integral multiplier adjusts for

error measurement and the amount of time that the error has existed. The integral multiplier adds to or

subtracts from the output in small increments to correct for the offset error caused by the proportional

contribution.

Deriv (D). The derivative multiplier (derivative) for this mode or actuator. The derivative multiplier

adjusts the output for rapid changes in the error, correcting for the rate of change of the error over time.

1 2 ... 18 19 20 21 22 23 24 25 26 27 28 ... 47 48

Pas de commentaire

APC ACRC500 Manuel d'installation Page 23