Carrier 17/19EX Manual De Usuario

vane response to chilled water temperature below deadband plus control point. It can be

adjusted on the LID from a setting of 2 to 10, and the default setting is 6.0. Increasing either of

these settings will cause the vanes to respond slower than a lower setting.

The

PROPORTIONAL ECW GAIN can be adjusted at the LID display from a setting of 1.0 to

3.0, with a default setting of 2.0. Increase this setting to increase guide vane response to a

change in entering chilled water temperature. The proportional bands and gain may be viewed/

modified on the Equipment Service3 table.

Demand Limiting

The PIC will respond to the

ACTIVE DEMAND LIMIT set point by limiting the opening of the

guide vanes. It will compare the set point to either

COMPRESSOR MOTOR LOAD or

COMPRESSOR MOTOR CURRENT (percentage), depending on how the control is configured

for the

DEMAND LIMIT SOURCE which is accessed on the SERVICE1 table. The default

setting is current limiting.

Machine Timers

The PIC maintains 2 runtime clocks, known as

COMPRESSOR ONTIME and SERVICE ON-

TIME. COMPRESSOR ONTIME indicates the total lifetime compressor run hours. This timer

can register up to 500,000 hours before the clock turns back to zero. The

SERVICE ONTIME is

a resettable timer that can be used to indicate the hours since the last service visit or any other

reason. The time can be changed through the LID to whatever value is desired. This timer can