York MILLENIUM 351-46, Руководство по эксплуатации

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JOHNSON CONTROLS
14
FORM 160.00-O1 (1020)
The older Turbo-Modulator capacity control boards
utilized a pre-programmed three dimensional surge sur-
face map for each compressor/refrigerant combination;
whereas the new ACC board automatically generates
its own “Adaptive” three dimensional surge surface map
while the chiller system is in operation. This “Adaptive”
operation is accomplished through the use of a patented
surge detection algorithm. The novel surge detection
system utilizes pressure information obtained from the
chillers’ pressure transducers in combination with the
VSD’s instantaneous power output to determine if the
system is in “surge”. Thus the adaptive system permits
construction of a custom compressor map for each
individual chiller system. Benefits of this new adaptive
system include: (1) a custom compressor map for each
installation which eliminates inefficient operation due to
the safety margin built into the previous programmed
map controller which was necessary to compensate for
compressor manufacturing tolerances (2) the ability to
update the system’s surge surface as the unit ages and
(3) automatic updating of the compressor map if changes
in refrigerant are implemented at a later date.
VSD and Optional Harmonic Filter
Logic Control Boards
Within the VSD enclosure, the VSD logic board and
optional Harmonic Filter logic boards are interconnected
via a 16 position ribbon cable which joins the two boards
together. The Filter Logic board derives its power from
the VSD Logic board over this ribbon cable. In addition
various logic level “handshake” signals convey the oper-
ating status of the VSD to the Filter and vice versa over
this cable. Finally, the cable includes a unidirectional
serial communications link which permits the transmis-
sion of a limited amount of data from the VSD to the
optional Harmonic Filter.
The VSD Logic board performs numerous functions,
including control of the VSD’s cooling fans and pumps,
control of the pre-charge contactor, control of the semi-
converter gating and generation of the PWM firing pulses
which are sent to the VSD gate driver and ultimately gate
the IGBT’s on and off.
The VSD Logic board also gathers data from the Cur-
rent Transformers which monitor the three phases of
motor current, the heatsink temperatures, the internal
ambient temperature within the enclosure and the DC
Link voltage. This data is periodically sent to the Micro
Computer Control Center via the ACC board.
CONTROL PANEL VSD RELATED
KEYPAD FUNCTIONS
The following keypad functions are in addition to the
standard keypad functions as addressed in the standard
chiller literature. The features below are present only
when the control panel is configured for operation with
the VSD:
Options Key – When depressed, the display will
show
VSD 100% JOB FLA = ___ A.
. Additional lines of display
are
available by scrolling, using the white key labeled, “Ad-
vance Day / Scroll”. All available lines are listed below:
VSD 100% JOB FLA = ___ A.
VSD DC LINK VOLTAGE = ___V.
VSD DC LINK CURRENT = ___A.
VSD INTERNAL AMBIENT TEMP = ___°F.
VSD CONVERTER HEATSINK TEMP = ___°F.
VSD PHASE A INVERTER HEATSINK TEMP = ___°F.
VSD PHASE B INVERTER HEATSINK TEMP = ___°F.
VSD PHASE C INVERTER HEATSINK TEMP = ___°F.
VSD PRECHARGE RELAY DE-ENERGIZED (or Energized)
VSD SCR GATE DRIVER DISABLED (or Enabled)
VSD COOLING PUMP STOPPED (or Running)
FILTER PRESENT (or Not Present)
When the Filter is Present, these additional lines are
available by scrolling:
FILTER HEATSINK TEMP = ___°F.
FILTER CURR: A=___A.; B=___A.; C=___A.
FILTER DC LINK VOLTAGE = ___V.
INPUT PEAK V.: A=___V.; B=___V.; C=___V.
FILTER STOPPED (Running)
FILTER PRECHARGE RELAY DE-ENERGIZED (Energized)
FILTER SUPPLY RELAY DE-ENERGIZED (Energized)
INPUT PHASE ROTATION - ABC (CBA)
VSD Parameters Key – When this key is pressed,
the VSD output frequency and voltage are displayed.
Additional lines of display are available by pressing the
white key labeled, “Advance Day / Scroll”. All available
lines are listed below:
OUTPUT FREQ __ HZ; OUTPUT VOLTS ___V.
OUTPUT CURR: A=___A.; B=___A.; C=___A.
INPUT POWER = ___KW; KWH = ____________