York YK Style H Operation Manual page 194

This shutdown occurs when the baseplate temperature exceeds 174°F (79°C). The chiller can be
started after the fault condition clears, the OVER-TEMP RESET button on the Filter Logic Board is
pressed, and the Clear Fault key is pressed on the display.
Harmonic Filter – High Baseplate Temperature
(VSD part number 371-03789-xxx (503HP 60 Hz; 419HP 50 Hz))
The chiller has shutdown because the baseplate temperature has increased to greater than 194°F.
The chiller can be started after the fault condition clears, the OVER-TEMP RESET button on the Filter
Logic Board is pressed and the Clear Fault key is pressed on the display.
VSD – Harmonic Filter-High Baseplate Temperature
(575V/60 Hz applications)
If the baseplate temperature rises above the following limits, this shutdown is performed:
• 424HP - 70.0°F, 174.2°C
• 608HP - 88.0°F, 190.4°C
Harmonic Filter – High Total Demand Distortion
This shutdown indicates the filter is not operating correctly and the input current to the VSD/Filter
is not sinusoidal. This shutdown will occur if the TDD exceeds 25% continuously for 45 seconds. TDD
is an acronym for Total Demand Distortion, a term defined by the IEEE Std 519-1992 standard as
the total root-sum-square harmonic current distortion, in percent of the maximum demand load
current (15 or 30 min demand). In the filter option supplied by YORK, the displayed TDD is the total
RMS value of all the harmonic current supplied by the main power to the VSD divided by the chiller
Full Load Amps, in percent. A standard VSD, less the optional filter typically has an input current
TDD level on the order of 28-30%. The chiller can be started after the Clear Fault key is pressed on
the display.
VSD – Low Frequency Detected
After a 20 second bypass after entering System Run, if the VSD frequency decreases to below 1 Hz
less than the minimum allowed frequency for 25 continuous seconds, this shutdown is initiated.
The minimum allowed frequency for the VSD is 25 Hz for 50 Hz units; 30 Hz for 60 Hz units. The
Clear Fault key is pressed on the display.
194 Model YK Style H Centrifugal Liquid Chillers with OptiView Control Center