Johnson Controls YORK YK MaxE, Operation Manual

Page: 157 / 184

FORM 160.54-O1
157
JOHNSON CONTROLS
2
“ HARMOnIC FILTER – PRECHARgE –
LOW DC BUS VOLTAgE
”
During pre-charge, the filter’s DC link must be equal to
or greater than 50VDC (41VDC for 50 Hz) within 1/10
second after the pre-charge relay is energized. If this
condition is not met, a shutdown is performed and this
message is generated.
“VSD-HARMOnIC FILTER-PRECHARgE-LOW
DC BUS VOLTAgE”
(575V/60Hz applications)
(Software version C.OPT.01.15.xxx (or later))
If the DC Link voltage does not reach at least 60VDC
(within 100 millisconds) or at least 630VDC (within 5
seconds) after the filter precharge command has been
received, this shutdown is performed.
“ HARMOnIC FILTER – LOW DC BUS
VOLTAgE ”
The Harmonic Filter generates its own filter DC link
voltage by switching its IGBT’s. This DC level is
actually higher than the level that one could obtain by
simply rectifying the input line voltage. Thus, the har-
monic filter actually performs a voltage “boost” func -
tion. This is necessary in order to permit current to flow
into the power line from the filter when the input line is
at its peak level. This shutdown occurs when the filter’s
DC link voltage decreases to a level less than 60VDC
below the filter DC link voltage setpoint. This Setpoint
is determined by the filter logic board via the sensing of
the three phase input line-to-line voltage. This setpoint
is set to the peak of the sensed input line-to-line voltage
plus 32 volts, not to exceed 760 volts and it varies with
the input line-to-line voltage. If this shutdown occurs
occasionally, the likely cause is a severe sag in the input
line voltage.
“ HARMOnIC FILTER – DC BUS VOLTAgE IM-
BALAnCE ”
The filter DC link is filtered by large, electrolytic ca -
pacitors, rated for 450VDC. These capacitors are wired
in series to achieve a 900VDC capability for the DC
link. It is important the voltage is shared equally from
the junction of the center or series capacitor connection,
to the negative bus and to the positive bus. This center
point should be approximately ½ of the total DC link
voltage.
“VSD-HARMOnIC FILTER-DC BUS VOLTAgE
IMBALAnCE”
(575V/60Hz applications)
(Software version C.OPT.01.15.xxx (or later))
If the Half DC Link Voltage does not remain within
± 63 VDC of the DC Link Voltage divided by 2, this
shutdown is performed.
“ HARMOnIC FILTER – InPUT
CURREnT OVERLOAD
”
The three phases of RMS filter current are monitored
and if any one of the three phases continuously exceeds
a given threshold for 7 seconds, a chiller shutdown is
performed and this message is displayed. The maximum
permissible continuous RMS current ratings for the
harmonic filter are:
351/292 HP = 128 AMPS
503/419 HP = 176 AMPS
790/658 HP = 277 AMPS
1048/917 HP = 385 AMPS
“ HARMOnIC FILTER – LOgIC BOARD
POWER SUPPLY ”
The low voltage power supplies on the filter logic board
have decreased below their permissible operating range.
The filter logic board receives its power from the VSD
logic board via the ribbon cable, connecting the two
boards.
“
HARMOnIC FILTER – RUn SIgnAL
”
When a digital run command is received at the filter logic
board from the VSD logic board via the 16 position ribbon
cable, a 1/10 second timer is started. If a redundant run
command does not occur on the serial data link from the
VSD logic board before the timer expires, a shutdown is
performed and this message is generated.
“ HARMOnIC FILTER – DC CURREnT
TRANSFORMER 1 ”
During initialization, with no current flowing through the
DC Current Transformers (DCCT’s), the DCCT output
voltages are measured and compared with a preset limit
via the filter logic board. If the measured values exceed
the preset limits, the DCCT’s are presumed to be defec-
tive and this shutdown is generated.
“ HARMOnIC FILTER – DC CURREnT
TRAnSFORMER 2 ”
See “Harmonic Filter – DC Current Transformer 1”
message above.