York VSD 292, Operation Manual

Page: 33 / 46

JOHNSON CONTROLS
33
SECTION 3 - SAFETY SHUTDOWNS
FORM 160.00-O4
ISSUE DATE: 07/31/2019
3
TABLE 3 - SAFETY SHUTDOWNS (CONT'D)
MESSAGE DESCRIPTION
VSD - Precharge Lockout
PRE-CHARGE FAULT LOCKOUT
If the OSCD fails to meet the pre-charge criteria (refer to pre-charge faults), the
pre-charge circuit will wait for a period of 10 seconds before another pre-charge
attempt. The unit’s cooling fans and coolant pump shall remain energized during
this time period. Following this 10-second period, the pre-charge shall again be
initiated. The unit shall attempt to meet the pre-charge criteria three consecutive
times before the OCSD will shutdown, lockout, and display this message.
Harmonic Filter - High
Baseplate Temperature
HIGH FILTER BASEPLATE
TEMPERATURE FAULT
A thermistor sensor is located inside the transistor module on the harmonic filter
power unit. If at anytime this thermistor detects a temperature higher then the
threshold value a shutdown will occur. Refer to the chart below for the shutdown
threshold values. A manual reset is required by pressing the “Overtemp Reset”
pushbutton located on the Filter Logic board.
DRIVE HP RATING THRESHOLD SHUTDOWN VALUE
270, 292, 351 175°F (79°C)
385, 419, 424, 503,
608 (575 VAC)
190°F (88°C)
608 (400 VAC), 704, 658, 790 194°F (90°C)
868, 882, 914, 917, 948, 1055 175°F (79°C)
Harmonic Filter - High Total
Demand Distortion
FLTR HIGH TDD FLT
The control center determines this shutdown by using data supplied from the
harmonic filter logic board. This shutdown indicates that the filter is not operating
correctly or the input current to the OSCD/filter system is not sinusoidal. This shut
-
down will occur if the Total Demand Distortion (TDD) in any one phase 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)”. The harmonic filter option was designed to provide an input
current TDD level of 8% or less for the OSCD system. A standard OSCD less the
optional filter typically has an input current TDD level on the order of 28 - 30%.