York MILLENIUM 351-46, Руководство по эксплуатации

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JOHNSON CONTROLS
4
FORM 160.00-O1 (1020)
VSD STYLE VARIATIONS
Original Style –
Model Number Part Number
351 -46 371-01742-XXX
503 -46 371-01484-XXX
790 -46 371-01749-XXX
Style “A” – This series applies to 503 HP only. Ground
fault protection was incorporated into the circuit breaker,
rather than utilizing separate GFI modules.
Model Number Part Number
503 - 46A 371-02241-XXX
Style “B” – This series includes wire harness changes
to address 50HZ, higher voltage scaling on the ‘519’
Filter Logic Board with matching software changes,
and various other software modifications. Note: Style
“B” Software cannot be installed in Style A units without
also making significant hardware changes.
Model Number Part Number
351 - 46B 371-02289-XXX
503 - 46B 371-02291-XXX
790 - 46B 371-02293-XXX
292 - 50B (50 HZ) 371-02249-XXX
419 - 50B (50 HZ) 371-02248-XXX
658 - 50B (50 HZ) 371-02247-XXX
Style “C” – This series is identical to the Style B series,
except that the circuit breaker and some fuses have been
changed to permit a 65,000 A. Short-Circuit Rating.
Model Number Part Number
351 - 46C 371-02412-XXX
503 - 46C 371-02413-XXX
790 - 46C 371-02414-XXX
292 - 50C (50 HZ) 371-02415-XXX
419 - 50C (50 HZ) 371-02416-XXX
658 - 50C (50 HZ) 371-02417-XXX
Style “D” – This series incorporates changes to the
‘519’ Filter Logic Board and Filter Gate Driver Board,
resulting in improved Percent TDD values:
Model Number Part Number
351 -46D 371-02526-XXX
503 -46D 371-02527-XXX
790 -46D 371-02528-XXX
1100 -46D 371-02461-XXX
292 -50D 371-02529-XXX
419 -50D 371-02530-XXX
658 -50D 371-02531-XXX
900 -50D 371-02532-XXX
- XXX Suffix:
-101 Factory Package YT Basic
-102 Factory Package YK Basic
-103 Factory Package YT w/ Filter
-104 Factory Package YK w/ Filter
-111 Retrofit YT Basic
-112 Retrofit YK Basic
-113 Retrofit YT w/ Filter
-114 Retrofit YK w/ Filter
VSD UNIT AND HARMONIC FILTER
COMPONENT OVERVIEW
Variable Speed Drive
The new YORK VSD is a liquid cooled, transistorized,
PWM inverter packaged in a compact cabinet small
enough to mount directly onto the chiller and directly onto
the motor. The power section of the drive is composed of
four major blocks: an AC to DC rectifier section with ac -
companying pre-charge circuit and free-wheeling diode,
a DC link filter section, a three phase DC to AC inverter
section and an output suppression network.
The AC to DC rectifier utilizes a semi-converter
formed by the connection of three SCR/diode modules
(1SCR-3SCR) in a three phase bridge configuration
(See Fig. 1). The modules are mounted on a liquid
cooled heatsink. Use of the semi-converter configura -
tion permits implementation of a separate pre-charge
circuit to limit the flow of current into the DC link filter
capacitors when the drive is switched on and it also
provides a fast disconnect from the power mains when
the drive is switched off. When the drive is turned off,
the SCRs in the semi-converter remain in a non-con-
ducting mode and the DC link filter capacitors remain
uncharged. When the drive is commanded to run, a set
of precharge resistors (1RES, 2RES) are switched into
the circuit by contactor 1M. The DC link filter capacitors
are slowly charged via the precharge resistors and the
diodes of the semi-converter for a fixed time period of 15
seconds. After the 15 second time period has expired,
the SCR’s are gated fully on and the contactor 1M is
dropped out. A “free-wheeling” diode 1CR is included
to reduce the surge current which must be conducted
through the semi-converter if a serious fault were to oc-
cur across the DC link. Three power fuses (1FU - 3FU)
and an electronic circuit breaker (1SW) with ground fault
sensing connects the AC to DC converter to the power
mains. Very fast semiconductor power fuses are utilized
to ensure that the SCR/diode module packages do not
rupture if a catastrophic failure were to occur on the DC
link. The SCR Trigger board (031-01472) provides the
gating pulses for the SCR’s as commanded by the VSD
Logic board (031-01433).
The DC Link filter section of the drive consists of two
basic components, a DC Link “smoothing” inductor or
pair of inductors (1L, 2L) and a series of electrolytic
filter capacitors (C1-C36). This inductor / capacitor
combination forms a low-pass L-C filter which effectively
smooths the ripple voltage from the AC to DC rectifier
while simultaneously providing a large energy reservoir
for use by the DC to AC inverter section of the drive.
In order to achieve a suitable voltage capability for the
capacitor portion of the filter, filter capacitor “banks” are
formed by connecting two capacitors in series to form a
“pair”, and then paralleling a suitable number of “pairs”