Carrier PC211 specifications Ramp Loading Control

Ramp Loading Control

The ramp loading control slows down the rate at which the compressor loads up. This control can prevent the compressor from loading up during the short period of time when the machine is started, and the chilled water loop has to be brought down to normal design conditions. This helps reduce electrical demand charges by slowly bringing the chilled water to control point.

However, the total power draw during this period remains almost unchanged.

There are 2 methods of ramp loading with the PIC. Ramp loading can be based on chilled water temperature or on motor load.

1.Temperature ramp loading limits the rate at which either leaving chilled water or entering chilled water temperature decreases by an operator-configured rate. The lowest temperature ramp table will be used the first time the machine is started (at commissioning). The lowest temperature ramp rate will also be used if machine power has been off for 3 hours or more (even if the motor ramp load is selected).

2.Motor load ramp loading limits the rate at which the compressor motor current or compressor motor load increases by an operator-configured rate.

The TEMP (Temperature) PULLDOWN, LOAD PULL DOWN, and SELECT RAMP TYPE

may be viewed/modified on the LID Equipment Configuration table, Config table (see Table 2). Motor load is the default type.