York VSD 292 User manual

Models VSD 270, 292, 351, 385, 419, 424, 503, 608, 658, 704, 790, 868, 882,
917, 948, and 1055
Models LVD 270, 292, 351, 385, 419, 424, 503, 608, 658, 704, and 900
LIQUID COOLED OPTISPEED
COMPRESSOR SPEED DRIVE
OPERATION MANUAL Supersedes: 160.00-O4 (1217) Form 160.00-O4 (719)
Issue Date:
July 31, 2019
VSD MODELS LVD MODELS
270 HP – 60 HZ, 400 VAC 608 HP – 60 HZ, 575 VAC 270 HP – 60 HZ, 380 VAC 608 HP – 60HZ, 575 VAC
292 HP – 50 HZ, 400 VAC 658 HP – 50 HZ, 380 VAC 270 HP – 60 HZ, 400 VAC 658 HP – 50 HZ, 400 VAC
292 HP – 50 HZ, 415 VAC 658 HP – 50 HZ, 400 VAC 292 HP – 50 HZ, 400 VAC 704 HP – 50 HZ, 415 VAC
351 HP – 60 HZ, 460 VAC 704 HP – 50 HZ, 415 VAC 292 HP – 50 HZ, 415 VAC 900 HP – 50 HZ, 400 VAC
385 HP – 60 HZ, 400 VAC 790 HP – 60 HZ, 460 VAC 351 HP – 60 HZ, 460 VAC 900 HP – 50 HZ, 415 VAC
419 HP – 50 HZ, 400 VAC 868 HP – 50 HZ, 380 VAC 385 HP – 60 HZ, 380 VAC
419 HP – 50 HZ, 415 VAC 882 HP – 60 HZ, 380 VAC 385 HP – 60 HZ, 400 VAC
424 HP – 60 HZ, 575 VAC 914 HP – 50 HZ, 400 VAC 419 HP – 50 HZ, 400 VAC
503 HP – 60 HZ, 460 VAC 917 HP – 60 HZ, 400 VAC 419 HP – 50 HZ, 415 VAC
608 HP – 60 HZ, 380 VAC 948 HP – 50 HZ, 415 VAC 424 HP – 60 HZ, 575 VAC
608 HP – 60 HZ, 400 VAC 1055 HP – 60 HZ, 460 VAC 503 HP – 60HZ, 460 VAC
035-27337-100

JOHNSON CONTROLS
2
FORM 160.00-O4
ISSUE DATE: 07/31/2019
This equipment is a relatively complicated apparatus.
During rigging, installation, operation, maintenance,
or service, individuals may be exposed to certain com-
ponents or conditions including, but not limited to:
heavy objects, refrigerants, materials under pressure,
rotating components, and both high and low voltage.
Each of these items has the potential, if misused or
handled improperly, to cause bodily injury or death. It
is the obligation and responsibility of rigging, instal-
lation, and operating/service personnel to identify and
recognize these inherent hazards, protect themselves,
and proceed safely in completing their tasks. Failure
to comply with any of these requirements could result
in serious damage to the equipment and the property in
IMPORTANT!
READ BEFORE PROCEEDING!
GENERAL SAFETY GUIDELINES
which it is situated, as well as severe personal injury or
death to themselves and people at the site.
This document is intended for use by owner-authorized
rigging, installation, and operating/service personnel. It
is expected that these individuals possess independent
training that will enable them to perform their assigned
tasks properly and safely. It is essential that, prior to
performing any task on this equipment, this individual
shall have read and understood the on-product labels,
this document and any referenced materials. This in-
dividual shall also be familiar with and comply with
all applicable industry and governmental standards and
regulations pertaining to the task in question.
SAFETY SYMBOLS
The following symbols are used in this document to alert the reader to specific situations:
Indicates a possible hazardous situation
which will result in death or serious injury
if proper care is not taken.
Indicates a potentially hazardous situa-
tion which will result in possible injuries
or damage to equipment if proper care is
not taken.
Identies a hazard which could lead to
damage to the machine, damage to other
equipment and/or environmental pollu-
tion if proper care is not taken or instruc-
tions and are not followed.
Highlights additional information useful
to the technician in completing the work
being performed properly.
External wiring, unless specied as an optional connection in the manufacturer’s product line, is not
to be connected inside the control cabinet. Devices such as relays, switches, transducers and controls
and any external wiring must not be installed inside the micro panel. All wiring must be in accor-
dance with Johnson Controls’ published specications and must be performed only by a qualied
electrician. Johnson Controls will NOT be responsible for damage/problems resulting from improper
connections to the controls or application of improper control signals. Failure to follow this warn-
ing will void the manufacturer’s warranty and cause serious damage to property or personal injury.

JOHNSON CONTROLS 3
FORM 160.00-O4
ISSUE DATE: 07/31/2019
CHANGEABILITY OF THIS DOCUMENT
In complying with Johnson Controls’ policy for con-
tinuous product improvement, the information con-
tained in this document is subject to change without
notice. Johnson Controls makes no commitment to
update or provide current information automatically
to the manual or product owner. Updated manuals, if
applicable, can be obtained by contacting the nearest
Johnson Controls Service office or accessing the John-
son Controls QuickLIT website at http://cgproducts.
johnsoncontrols.com.
It is the responsibility of rigging, lifting, and operating/
service personnel to verify the applicability of these
documents to the equipment. If there is any question
regarding the applicability of these documents, rig-
ging, lifting, and operating/service personnel should
verify whether the equipment has been modified and
if current literature is available from the owner of the
equipment prior to performing any work on the chiller.
CHANGE BARS
Revisions made to this document are indicated with a
line along the left or right hand column in the area the
revision was made. These revisions are to technical in-
formation and any other changes in spelling, grammar
or formatting are not included.
MANUAL DESCRIPTION FORM NUMBER
Wiring Diagrams - Field Connections YK Style F and G - LV VSD 160.54-PW6
Wiring Diagrams - OptiView Control Center YK Style G and SSS, LV VSD, MV VSD 160.75-PW6
Wiring Diagrams - OptiView Control Center YK Style G and SSS, LV VSD, MV VSD with the LTC
I/O Board 160.75-PW8
Wiring Diagrams - Field Control Modications YK Style G 160.75-PW4
Wiring Diagrams - Field Connections YK Style H - LV VSD 160.76-PW7
Wiring Diagrams - OptiView Control Center YK Style H and SSS, LV VSD, MV VSD 160.76-PW6
Wiring Diagrams - Field Control Modications YK Style H 160.76-PW4
Chiller Operation and Maintenance YK Style G 160.75-O1
Operation OptiView Panel YK Style G 160.54-O1
Chiller Operation and Maintenance YK Style H 160.76-O1
Operation OptiView Panel YK Style H 160.76-O2
ASSOCIATED LITERATURE

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FORM 160.00-O4
ISSUE DATE: 07/31/2019
W
NOMENCLATURE
VSD351_RKFT- 46
Voltage Rating: 40 = 400 VAC, 60 Hz
46 = 460 VAC, 60 Hz
50 = 400 VAC, 50 Hz
58 = 575 VAC, 60 Hz
68 = 415 VAC, 50 Hz
Optional 519: Filter-Installed (FT) or Not (_)
Chiller Type: YK (K), YT (T)
Retrot Package (R), Factory Package (_)
Horsepower Rating: 270, 292, 351, 385, 419, 424, 503, 608
Type of Drive
(W) Asia, (_) Global Design
OPTISPEED™ MODEL PART NUMBERS
The X in the part number below indicates which type of communications is used between the Micropanel and the
OSCD: 1 = YORK Protocol, 7 = MODBUS Protocol, 8 = MODBUS with CPC, W = Asia (W in the 4th position
taking place of the first hyphen in the part number)
TABLE 1 - VSD PART NUMBERS AND DESCRIPTIONS
MODEL PART NUMBER DESCRIPTION
60 HZ 50 HZ
270 HP
400 VAC
VSD270T-40 371-02767-X21 Factory Pack, YT Base Model
VSD270K-40 371-02767-X22 Factory Pack, YK Base Model
VSD270TFT-40 371-02767-X25 Factory Pack, YT Filter Model
VSD270KFT-40 371-02767-X26 Factory Pack, YK Filter Model
VSD270RT-40 371-02767-X31 Retrot, YT Base Model
VSD270RK-40 371-02767-X32 Retrot, YK Base Model
VSD270RTFT-40 371-02767-X35 Retrot, YT Filter Model
VSD270RKFT-40 371-02767-X36 Retrot, YK Filter Model
292 HP
400 VAC
VSD292T-50 371-03700-X01 Factory Pack, YT Base Model
VSD292K-50 371-03700-X02 Factory Pack, YK Base Model
VSD292TFT-50 371-03700-X05 Factory Pack, YT Filter Model
VSD292KFT-50 371-03700-X06 Factory Pack, YK Filter Model
VSD292RT-50 371-03700-X11 Retrot, YT Base Model
VSD292RK-50 371-03700-X12 Retrot, YK Base Model
VSD292RTFT-50 371-03700-X15 Retrot, YT Filter Model
VSD292RKFT-50 371-03700-X16 Retrot, YK Filter Model
W-VSD292K-50 371W06040-X02 Factory Pack, YK Base Model
W-VSD292KFT-50 371W06040-X06 Factory Pack, YK Filter Model

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FORM 160.00-O4
ISSUE DATE: 07/31/2019
MODEL PART NUMBER DESCRIPTION
60 HZ 50 HZ
292 HP
415 VAC
VSD292T-68 371-03700-X21 Factory Pack, YT Base Model
VSD292K-68 371-03700-X22 Factory Pack, YK Base Model
VSD292TFT-68 371-03700-X25 Factory Pack, YT Filter Model
VSD292KFT-68 371-03700-X26 Factory Pack, YK Filter Model
VSD292RT-68 371-03700-X31 Retrot, YT Base Model
VSD292RK-68 371-03700-X32 Retrot, YK Base Model
VSD292RTFT-68 371-03700-X35 Retrot, YT Filter Model
VSD292RKFT-68 371-03700-X36 Retrot, YK Filter Model
W-VSD292K-68 371W06040-X22 Factory Pack, YK Base Model
W-VSD292KFT-68 371W06040-X26 Factory Pack, YK Filter Model
351 HP
460 VAC
VSD351T-46 371-02767-X01 Factory Pack, YT Base Model
VSD351K-46 371-02767-X02 Factory Pack, YK Base Model
VSD351TFT-46 371-02767-X05 Factory Pack, YT Filter Model
VSD351TFK-46 371-02767-X06 Factory Pack, YK Filter Model
VSD351RT-46 371-02767-X11 Retrot, YT Base Model
VSD351RK-46 371-02767-X12 Retrot, YK Base Model
VSD351RTFT-46 371-02767-X15 Retrot, YT Filter Model
VSD351RTFK-46 371-02767-X16 Retrot, YK Filter Model
385 HP
400 VAC
VSD385T-40 371-03789-X21 Factory Pack, YT Base Model
VSD385K-40 371-03789-X22 Factory Pack, YK Base Model
VSD385TFT-40 371-03789-X23 Factory Pack, YT Filter Model
VSD385KFT-40 371-03789-X24 Factory Pack, YK Filter Model
VSD385RT-40 371-03789-X31 Retrot, YT Base Model
VSD385RK-40 371-03789-X32 Retrot, YK Base Model
VSD385RTFT-40 371-03789-X33 Retrot, YT Filter Model
VSD385RKFT-40 371-03789-X34 Retrot, YK Filter Model
419 HP
400 VAC
VSD419T-50 371-03789-X05 Factory Pack, YT Base Model
VSD419K-50 371-03789-X06 Factory Pack, YK Base Model
VSD419TFT-50 371-03789-X07 Factory Pack, YT Filter Model
VSD419KFT-50 371-03789-X08 Factory Pack, YK Filter Model
VSD419RT-50 371-03789-X15 Retrot, YT Base Model
VSD419RK-50 371-03789-X16 Retrot, YK Base Model
VSD419RTFT-50 371-03789-X17 Retrot, YT Filter Model
VSD419RKFT-50 371-03789-X18 Retrot, YK Filter Model
W-VSD419K-50 371W06431-X06 Factory Pack, YK Base Model
W-VSD419KFT-50 371W06431-X08 Factory Pack, YK Filter Model
W-VSD419T-50 371-05395-X05 Factory Pack, YT Base Model
W-VSD419K-50 371-05395-X06 Factory Pack, YK Base Model
W-VSD419TFT-50 371-05395-X07 Factory Pack, YT Filter Model
W-VSD419KFT-50 371-05395-X08 Factory Pack, YK Filter Model
W-VSD419RT-50 371-05395-X15 Retrot, YT Base Model
W-VSD419RK-50 371-05395-X16 Retrot, YK Base Model
W-VSD419RTFT-50 371-05395-X17 Retrot, YT Filter Model
W-VSD419RKFT-50 371-05395-X18 Retrot, YK Filter Model
TABLE 1 - VSD PART NUMBERS AND DESCRIPTIONS (CONT'D)

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FORM 160.00-O4
ISSUE DATE: 07/31/2019
MODEL PART NUMBER DESCRIPTION
60 HZ 50 HZ
419 HP
415 VAC
VSD419T-68 371-03789-X25 Factory Pack, YT Base Model
VSD419K-68 371-03789-X26 Factory Pack, YK Base Model
VSD419TFT-68 371-03789-X27 Factory Pack, YT Filter Model
VSD419KFT-68 371-03789-X28 Factory Pack, YK Filter Model
VSD419RT-68 371-03789-X35 Retrot, YT Base Model
VSD419RK-68 371-03789-X36 Retrot, YK Base Model
VSD419RTFT-68 371-03789-X37 Retrot, YT Filter Model
VSD419RKFT-68 371-03789-X38 Retrot, YK Filter Model
W-VSD419K-68 371W06431-X26 Factory Pack, YK Base Model
W-VSD419KFT-68 371W06431-X28 Factory Pack, YK Filter Model
424 HP
575 VAC
VSD424T-58 371-04881-X01 Factory Pack, YT Base Model
VSD424K-58 371-04881-X02 Factory Pack, YK Base Model
VSD424TFT-58 371-04881-X03 Factory Pack, YT Filter Model
VSD424TFK-58 371-04881-X04 Factory Pack, YK Filter Model
VSD424RT-58 371-04881-X11 Retrot, YT Base Model
VSD424RK-58 371-04881-X12 Retrot, YK Base Model
VSD424RTFT-58 371-04881-X13 Retrot, YT Filter Model
VSD424RTFK-58 371-04881-X14 Retrot, YK Filter Model
503 HP
460 VAC
VSD503T-46 371-03789-X01 Factory Pack, YT Base Model
VSD503K-46 371-03789-X02 Factory Pack, YK Base Model
VSD503TFT-46 371-03789-X03 Factory Pack, YT Filter Model
VSD503TFK-46 371-03789-X04 Factory Pack, YK Filter Model
VSD503RT-46 371-03789-X11 Retrot, YT Base Model
VSD503RK-46 371-03789-X12 Retrot, YK Base Model
VSD503RTFT-46 371-03789-X13 Retrot, YT Filter Model
VSD503RTFK-46 371-03789-X14 Retrot, YK Filter Model
608 HP
380 VAC
VSD608K-40 371-06982-X22 Factory Pack, YK Base Model
VSD608KFT-40 371-06982-X24 Factory Pack, YK Filter Model
VSD608RK-40 371-06982-X32 Retrot, YK Base Model
VSD608RKFT-40 371-06982-X34 Retrot, YK Filter Model
608 HP
400 VAC
VSD608K-42 371-06982-X46 Factory Pack, YK Base Model
VSD608KFT-42 371-06982-X48 Factory Pack, YK Filter Model
VSD608RK-42 371-06982-X56 Retrot, YK Base Model
VSD608RKFT-42 371-06982-X58 Retrot, YK Filter Model
608 HP
575 VAC
VSD608T-58 371-04563-X01 Factory Pack, YT Base Model
VSD608K-58 371-04563-X02 Factory Pack, YK Base Model
VSD608TFT-58 371-04563-X03 Factory Pack, YT Filter Model
VSD608KFT-58 371-04563-X04 Factory Pack, YK Filter Model
VSD608RT-58 371-04563-X11 Retrot, YT Base Model
VSD608RK-58 371-04563-X12 Retrot, YK Base Model
VSD608RTFT-58 371-04563-X13 Retrot, YT Filter Model
VSD608RKFT-58 371-04563-X14 Retrot, YK Filter Model
TABLE 1 - VSD PART NUMBERS AND DESCRIPTIONS (CONT'D)

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FORM 160.00-O4
ISSUE DATE: 07/31/2019
TABLE 1 - VSD PART NUMBERS AND DESCRIPTIONS (CONT'D)
MODEL PART NUMBER DESCRIPTION
60 HZ 50 HZ
658 HP
380 VAC
VSD658K-50 371-06982-X06 Factory Pack, YK Base Model
VSD658KFT-50 371-06982-X08 Factory Pack, YK Filter Model
VSD658RK-50 371-06982-X16 Retrot, YK Base Model
VSD658RKFT-50 371-06982-X18 Retrot, YK Filter Model
W-VSD658K-50 371W06212-X02 Factory Pack, YK Base Model
W-VSD658KFT-50 371W06212-X04 Factory Pack, YK Filter Model
658 HP
400 VAC
VSD658K-43 371-06982-X62 Factory Pack, YK Base Model
VSD658KFT-43 371-06982-X64 Factory Pack, YK Filter Model
VSD658RK-43 371-06982-X72 Retrot, YK Base Model
VSD658RKFT-43 371-06982-X74 Retrot, YK Filter Model
704 HP
415 VAC
VSD704K-68 371-06982-X26 Factory Pack, YK Base Model
VSD704KFT-68 371-06982-X28 Factory Pack, YK Filter Model
VSD704RK-68 371-06982-X36 Retrot, YK Base Model
VSD704RKFT-68 371-06982-X38 Retrot, YK Filter Model
W-VSD704K-68 371W06212-X22 Factory Pack, YK Base Model
W-VSD704KFT-68 371W06212-X24 Factory Pack, YK Filter Model
790 HP
460 VAC
VSD790K-46 371-06982-X02 Factory Pack, YK Base Model
VSD790KFT-46 371-06982-X04 Factory Pack, YK Filter Model
VSD790RK-46 371-06982-X12 Retrot, YK Base Model
VSD790RKFT-46 371-06982-X14 Retrot, YK Filter Model
868 HP
380 VAC
VSD868K-50 371-06863-X06 Factory Pack, YK Base Model
VSD868KFT-50 371-06863-X08 Factory Pack, YK Filter Model
VSD868RK-50 371-06863-X16 Retrot, YK Base Model
VSD868RKFT-50 371-06863-X18 Retrot, YK Filter Model
882 HP
380 VAC
VSD882K-40 371-06863-X22 Factory Pack, YK Base Model
VSD882KFT-40 371-06863-X24 Factory Pack, YK Filter Model
VSD882RK-40 371-06863-X32 Retrot, YK Base Model
VSD882RKFT-40 371-06863-X34 Retrot, YK Filter Model
914 HP
400 VAC
VSD914K-43 371-06863-X62 Factory Pack, YK Base Model
VSD914KFT-43 371-06863-X64 Factory Pack, YK Filter Model
VSD914RK-43 371-06863-X72 Retrot, YK Base Model
VSD914RKFT-43 371-06863-X74 Retrot, YK Filter Model
917 HP
400 VAC
VSD917K-42 371-06863-X46 Factory Pack, YK Base Model
VSD917KFT-42 371-06863-X48 Factory Pack, YK Filter Model
VSD917RK-42 371-06863-X56 Retrot, YK Base Model
VSD917RKFT-42 371-06863-X58 Retrot, YK Filter Model
948 HP
415 VAC
VSD948K-68 371-06863-X26 Factory Pack, YK Base Model
VSD948KFT-68 371-06863-X28 Factory Pack, YK Filter Model
VSD948RK-68 371-06863-X36 Retrot, YK Base Model
VSD948RKFT-68 371-06863-X38 Retrot, YK Filter Model
1055 HP
460 VAC
VSD1055K-46 371-06863-X02 Factory Pack, YK Base Model
VSD1055KFT-46 371-06863-X04 Factory Pack, YK Filter Model
VSD1055RK-46 371-06863-X12 Retrot, YK Base Model
VSD1055RKFT-46 371-06863-X14 Retrot, YK Filter Model

JOHNSON CONTROLS
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FORM 160.00-O4
ISSUE DATE: 07/31/2019
NOMENCLATURE
I II III IV V VI VII VIII IX X XI XII XIII XIV
LVD 0503 G R N01 K C 30 B 06 L Z - 46 A
I - Drive Type
LVD
(historical models)
VSD
TM
HYP
II - Horsepower and Amp Rating
(4 digits fixed length)
III - Design Center/Source
G = Global Design
W = Asia Design
T = Toshiba
B = Benshaw
IV - VSD Mounting Method
X = Unit Mount (Factory Pack)
R = Remote Mount (Floor Standing)
V - Enclosure Type Rating
N01 = NEMA 1
N04 = NEMA4
N3R = NEMA 3R
I33 = IP33
*** = Not yet defined
VI - Chiller Type
H = YMC2 (YH)
K = YK
T = YT
VII - Chiller Cooling Method/VSD Cooling
Medium
C = Condenser liquid cooled / water
E = Evaporator liquid cooled / water
D = Condenser liquid cooled / glycol
F = Evaporator liquid cooled / glycol
B = Air cooled / glycol
A = Air cooled / air
R = Refrigerant / refrigerant
* = Not yet defined
VIII - Liquid DWP
15 = 150 psig
30 = 300 psig
* = Not yet defined
IX - Input Connection
D = Disconnect Switch
B = Circuit Breaker
T = Terminal Block
* = Not yet defined
X - Input Connection Rating
04 = 400 A
06 = 600 A
08 = 800 A
10 = 1000 A
12 = 1200 A
00 = None (terminal block)
* = Not yet defined
XI - Code Agency Approval
L = cUL/cETL
C = CE
G =GB
Q = Special
X = None
XII - Harmonic Mitigation
F = Filter Model
Z = Base Model
A = Active Front End Model
XIII - Input Voltage/Frequency
(Per M-527)
40 = 380/400 V 60 Hz
50 = 380/400 V 50 Hz
42 = 400 V 60 Hz
46 = 460 V 60 Hz
68 = 415 V 50 Hz
58 = 575 V 60 Hz
XIV - Product Mod Level Suffix
A = Mod Level "A"
B = Mod Level "B"

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FORM 160.00-O4
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TABLE 2 - LVD PART NUMBERS AND DESCRIPTIONS
MODEL NUMBER PART NUMBER DESCRIPTION
270 HP – 60 HZ, 380 – 400 VAC LVD0270GXN01KC30B04LZ-40A 371-06976-X22 Factory Pack, YK Chiller
270 HP – 60 HZ, 400 VAC LVD0270GXN01KC30B04LZ-42A 371-06976-X46 Factory Pack, YK Chiller
(Saudi)
292 HP – 50 HZ, 400 VAC LVD0292WXI22KC30B04GZ-50A 371W06640-X02 Factory Pack, YK Chiller
292 HP – 50 HZ, 380 – 400 VAC LVD0292GXN01KC30B04LZ-50A 371-06976-X06 Factory Pack, YK Chiller
292 HP – 50 HZ, 415 VAC LVD0292WXI22KC30B04GZ-68A 371W06640-X22 Factory Pack, YK Chiller
292 HP – 50 HZ, 415 VAC LVD0292GXN01KC30B04LZ-68A 371-06976-X26 Factory Pack, YK Chiller
351 HP – 60 HZ, 460 VAC LVD0315GXN01KC30B04LZ-46A 371-06976-X02 Factory Pack, YK Chiller
385 HP – 60 HZ, 380 – 400 VAC LVD0385GXN01KC30B06LZ-40A 371-06697-X22 Factory Pack, YK Chiller
385 HP – 60 HZ, 400 VAC LVD0385GXN01KC30B06LZ-42A 371-06697-X46 Factory Pack, YK Chiller
419 HP – 50 HZ, 380 – 400 VAC LVD0419GXN01KC30B06LZ-50A 371-06697-X06 Factory Pack, YK Chiller
419 HP – 50 HZ, 400 VAC LVD0419WXI22KC30B06GZ-50A 371W06642-X06 Factory Pack, YK Chiller
419 HP – 50 HZ, 415 VAC LVD0419WXI22KC30B06GZ-68A 371W06642-X26 Factory Pack, YK Chiller
419 HP – 50 HZ, 415 VAC LVD0419GXN01KC30B06LZ-68A 371-06697-X26 Factory Pack, YK Chiller
424 HP – 60 HZ, 575 VAC LVD0424GXN01KC30B04LZ-58A 371-06976-X42 Factory Pack, YK Chiller
503 HP – 60 HZ, 460 VAC LVD0503GXN01KC30B06LZ-46A 371-06697-X02 Factory Pack, YK Chiller
608 HP – 60 HZ, 575 VAC LVD0608GXN01KC30B06LZ-58A 371-06697-X42 Factory Pack, YK Chiller
658 HP – 50 HZ, 400 VAC LVD0658WXI22KC30B10GZ-50A 371W06644-X02 Factory Pack, YK Chiller
704 HP – 50 HZ, 415 VAC LVD0704WXI22KC30B10GZ-68A 371W06644-X22 Factory Pack, YK Chiller
900 HP – 50 HZ, 400 VAC LVD0900WXI22KC30B12GZ-50A 371W06646-X02 Factory Pack, YK Chiller
900 HP – 50 HZ, 415 VAC LVD0900WXI22KC30B12GZ-68A 371W06646-X22 Factory Pack, YK Chiller
OPTISPEED™ MODEL PART NUMBERS (CONT'D)
The X in the part number below indicates which type of communications is used between the Micropanel and the
OSCD: 1 = YORK Protocol, 7 = MODBUS Protocol, 8 = MODBUS w/ CPC, W = Asia (4th position taking place
of the first hyphen in the part number)

JOHNSON CONTROLS
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FORM 160.00-O4
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TABLE OF CONTENTS
SECTION 1 - GENERAL INFORMATION ..............................................................................................................13
OptiSpeed/Harmonic Filter Component Overview ........................................................................................13
Differences Between the G and W Designs ...................................................................................................15
Differences for the VSD and LVD Model Drives .............................................................................................15
OptiSpeed Compressor Drive Control System Overview ..............................................................................15
VSD Adaptive Capacity Control...................................................................................................................... 17
SECTION 2 - OPTISPEED COMPRESSOR DRIVE DETAILS ..............................................................................19
SECTION 3 - SAFETY SHUTDOWNS....................................................................................................................31
General Information .......................................................................................................................................31
Motor or Starter – Current Imbalance............................................................................................................. 31
VSD - 105 % Motor Current Overload............................................................................................................31
VSD - High Converter Heatsink Temperature.................................................................................................32
VSD - High Inverter Baseplate Temperature (270, 292, 351 and 424 Hp drives) .......................................... 32
VSD - High Phase (X) Inverter Baseplate Temperature
(on models where 3 transistors modules are used) ................................................................................32
VSD - Precharge Lockout...............................................................................................................................33
Harmonic Filter - High Baseplate Temperature ..............................................................................................33
Harmonic Filter - High Total Demand Distortion .............................................................................................33
SECTION 4 - CYCLING SHUTDOWNS..................................................................................................................35
General Information........................................................................................................................................35
VSD - DC Bus Voltage Imbalance..................................................................................................................35
VSD - High DC Bus Voltage ...........................................................................................................................35
VSD - High Internal Ambient Temperature .....................................................................................................35
VSD - High Phase A (or B, C) Instantaneous Current ....................................................................................36
VSD - Initialization Failed ...............................................................................................................................36
VSD - Invalid Current Scale Selection............................................................................................................ 36
VSD - Logic Board Power Supply ..................................................................................................................36
VSD - Logic Board Processor ........................................................................................................................36
VSD - Low Converter Heatsink Temperature .................................................................................................36
VSD - Low DC Bus Voltage............................................................................................................................36
VSD - Low Inverter Baseplate Temperature................................................................................................... 37
VSD - Phase A (or B, C) Gate Driver.............................................................................................................. 37
VSD - Precharge - DC Bus Voltage Imbalance .............................................................................................. 37
VSD - Precharge - Low DC Bus Voltage ........................................................................................................37
VSD - Run Signal ...........................................................................................................................................37
VSD - Serial Communications........................................................................................................................37
VSD - Single Phase Input Power ...................................................................................................................37
VSD - Stop Contacts Open ............................................................................................................................37
Harmonic Filter - 110 % Input Current Overload ............................................................................................ 38
Harmonic Filter - DC Bus Voltage Imbalance.................................................................................................38
Harmonic Filter - DC Current Transformer 1 (or 2).........................................................................................38
Harmonic Filter - High DC Bus Voltage ..........................................................................................................38
Harmonic Filter - High Phase A (or B, C) Current...........................................................................................38
Harmonic Filter Communications ...................................................................................................................39
Harmonic Filter - Logic Board Power Supply .................................................................................................39

JOHNSON CONTROLS 11
FORM 160.00-O4
ISSUE DATE: 07/31/2019
Harmonic Filter - Low DC Bus Voltage...........................................................................................................39
Harmonic Filter - Phase Locked Loop ............................................................................................................39
Harmonic Filter - Precharge - Low DC Bus Voltage ....................................................................................... 39
Harmonic Filter - Run Signal ..........................................................................................................................39
SECTION 5 - WARNING MESSAGES....................................................................................................................41
General Information........................................................................................................................................41
Warning - Vanes Uncalibrated - Fixed Speed ................................................................................................ 41
Warning - Harmonic Filter - Data Loss ...........................................................................................................41
Warning - Harmonic Filter - Operation Inhibited .............................................................................................41
SECTION 6 - VSD FREQUENTLY ASKED QUESTIONS .....................................................................................43
TABLE OF CONTENTS (CONT'D)

JOHNSON CONTROLS
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FORM 160.00-O4
ISSUE DATE: 07/31/2019
LIST OF FIGURES
LIST OF TABLES
TABLE 1 - VSD Part Numbers And Descriptions ......................................................................................................4
TABLE 2 - LVD Part Numbers And Descriptions.......................................................................................................9
TABLE 3 - Safety Shutdowns..................................................................................................................................31
TABLE 4 - Cycling Shutdown Message ..................................................................................................................35
TABLE 5 - Warning Messages................................................................................................................................41
TABLE 6 - SI Metric Conversion .............................................................................................................................45
FIGURE 1 - OptiSpeed System Architecture
(Model VSD 351 without Harmonic Filter shown, similar to 270, 292, 424 Models)............................19
FIGURE 2 - OptiSpeed System Architecture
(Model LVD 419 shown, similar to 385, 503, 608, 658, 704, and 900 Models) ..................................21
FIGURE 3 - OptiSpeed System Architecture
(Model LVD 419 shown, similar to 385, 503, 608, 658, 704, and 900 Models) ...................................21
FIGURE 4 - OptiSpeed System Architecture
(Model VSD 503 with Harmonic Filter shown, similar to 385, 419, 608 Models).................................22
FIGURE 5 - OptiSpeed System Architecture
(Model VSD 790 shown, similar to 608, 658, and 704 Models) .........................................................24
FIGURE 6 - OptiSpeed System Architecture
(Model 1055 shown, similar to 868, 882, 914, 917, and 948 Models) ...............................................26
FIGURE 7 - VSD Logic Board (Located on Panel Door).........................................................................................28
FIGURE 8 - SCR Trigger Board ..............................................................................................................................28
FIGURE 9 - Optional Harmonic Filter Logic Board (Located on Panel Door)..........................................................29
FIGURE 10 - Gate Driver Board and Power Module
(Model 351 shown, similar to 270, 292, 424 Models) ........................................................................29

JOHNSON CONTROLS 13
FORM 160.00-O4
ISSUE DATE: 07/31/2019
1
SECTION 1 - GENERAL INFORMATION
This instruction is to be used in conjunction with the
Operation Instructions for YORK Centrifugal chillers
furnished with an optional OptiSpeed™ Compressor
Drive (OSCD).
OPTISPEED/HARMONIC FILTER COMPONENT
OVERVIEW
OptiSpeed Compressor Drive 270, 292, 351,
and 424 Hp (Low HP Model)
The YORK® OptiSpeed Compressor Drive (OSCD) is
a liquid cooled, transistorized, PWM inverter in a high-
ly integrated package. This package is small enough
to mount directly onto the chiller motor, and small
enough to be applied in many retrofit chiller applica-
tions. The power section of the drive is composed of
four major blocks: an AC to DC rectifier section with
an integrated pre-charge circuit, a DC bus filter sec-
tion, a three phase DC to AC inverter section and an
output suppression network.
An electronic circuit breaker with ground fault sens-
ing connects the AC line to an AC line inductor and
then to the DC converter. The line inductor will limit
the amount of fault current so that the electronic circuit
breaker is sufficient for protecting the OSCD. Input
fuses to the OSCD are no longer needed. The follow-
ing description of operation is specific for the 351 Hp
OSCD unless otherwise noted.
The AC to DC converter uses 3 Silicon Controlled
Rectifiers (SCRs) and 3 diodes. One SCR and one di-
ode are contained in each module. Three modules are
required to converter the 3 phase input AC voltage into
DC voltage. The modules are mounted on the bottom
of the liquid cooled heatsink. The use of the SCRs in
the converter permits pre-charge of the DC bus capaci-
tors when the chiller enters the prelube cycle, and it
also provides a fast disconnect from the AC line when
the chiller enters the coastdown cycle. At this time, the
OSCD is turned off, the SCRs in the converter are no
longer turned on and remain in a turned off condition
until the next pre-charge cycle. The DC bus capacitors
will start to discharge through the bleeder resistors.
When the chiller enters the prelube cycle, the OSCD is
commanded to pre-charge and the SCRs are gradually
turned on to slowly charge the DC bus capacitors. This
is called the pre-charge period, which last for 20-sec-
onds. At this time the SCRs are fully turned on. The
SCR Trigger board provides the turn on commands for
the SCRs. The OSCD Logic board provides the com-
mand to the SCR trigger board when to precharge.
Although many of these parts are similar
to the parts used in previous Variable
Speed Drive (VSD) designs, these parts
are only compatible with drives having the
base part numbers included on the cover
of this form. Failure to use the correct
parts may cause major damage to these
and other components in the drive. For
example, the VSD logic board 031-02077-
000 used in this drive is not compatible
with 031-01433-000 logic board used in
previous designs. A new VSD logic board
was designed in 2006. The part number
of the new board is 031-02506-002. The
part number of the new board for the
575 VAC application is 031-02506-003.
The software is not interchangeable be-
tween the 575 VAC version and all other
applications. Also the software is not
interchangeable between the 031-01433,
031-02077, or the 031-02506 boards.
The DC Bus filter section of the drive consists of one
basic component, a series of electrolytic filter capaci-
tors. The capacitors provide a large energy reservoir
for use by the DC to AC inverter section of the OSCD.
The capacitors are contained in the OSCD Power Unit.
“Bleeder” resistors are mounted on the side of the
Power Unit to provide a discharge path for the stored
energy in the capacitors.
The DC to AC inverter section of the OSCD serves
to convert the DC voltage to AC voltage at the proper
magnitude and frequency as commanded by the OSCD
Logic board. The inverter section is actually composed
of one power unit. This power unit contains one very
fast switching transistor module mounted on the same
liquid cooled heatsink as the converter modules, the
DC Bus capacitors, and an OSCD Gate Driver board.
The gate driver board provides the turn on and turn off
commands to the output transistors. The OptiSpeed
Compressor Drive Logic board determines when the
turn on and turn off commands should occur. The gate
driver board is mounted directly on top of the transistor
module, and it is held in place with mounting screws
and soldered to the transistor module.

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FORM 160.00-O4
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SECTION 1 - GENERAL INFORMATION
The OSCD output suppression network is composed
of a series of capacitors and resistors. The job of the
suppressor network is to increase the time it takes for
the output voltage to switch as seen by the motor, and
reduce the peak voltage applied to the motor windings.
This network protects the compressor motor from prob-
lems commonly associated with PWM motor drives.
Other sensors and boards are used to provide safe oper-
ation of the OptiSpeed Compressor Drive. The transis-
tor module and heatsink have thermistors mounted on
them to provide temperature information to the OSCD
logic board. These sensors protect the OSCD from over
temperature conditions. A Bus Voltage Isolator board is
used to ensure that the DC bus capacitors are properly
charged. Three output current transformers protect the
OSCD and motor from over current conditions.
OptiSpeed Compressor Drive 385, 419, 503,
608, 658, 704, 790, 868, 882, 914, 917, 948, and
1055 Hp (High HP Model)
The high HP models' OSCDs function in the same
manner as the low HP models, and have the same ba-
sic components. The power requirements of these high
horsepower drives require more capacitors in the DC
Bus and 3 output transistor sections are needed. One
section is used for each output phase. Each transistor
module within the output transistor section contains
a thermistor, which is connected to the OSCD logic
board. The transistor gate driver board is mounted on
top of the transistor section in the same manner as the
low horsepower model, but it only contains 2 transis-
tor drivers. The modules and gate driver boards are not
interchangeable between the various models.
Harmonic Filter Option
The VSD model of OptiSpeed Compressor Drive
(OSCD) system may also include an optional harmon-
ic filter and high frequency trap designed to meet the
IEEE Std 519, “IEEE Recommended Practices and Re-
quirements for Harmonic Control in Electrical Power
Systems”. The harmonic filter is offered as a means
to improve the input current waveform drawn by the
OSCD from the AC line, thus reducing the possibil-
ity of causing electrical interference with other sensi-
tive electronic equipment connected to the same power
source. An additional benefit of the optional harmonic
filter is that it will correct the system power factor to
nearly unity.
The power section of the Harmonic Filter is composed
of three major blocks: a pre-charge section, a three
phase inductor and a Filter Power Unit.
The pre-charge section contains pre-charge resistors, a
pre-charge contactor and a supply contactor. The pre-
charge network serves two purposes, to slowly charge
the DC bus capacitors associated with the Filter Power
Unit, and to provide a means of disconnecting the fil-
ter power unit from the AC line. When the chiller is
turned off, both contactors are de-energized and the fil-
ter power unit is disconnected from the AC line. When
the chiller starts to run, the pre-charge resistors are
switched into the circuit via the precharge contactor for
a fixed time period of 5 seconds. This permits the fil-
ter capacitors in the filter power unit to slowly charge.
After the 5-second time period, the supply contactor is
energized and the pre-charge contactor is de-energized,
permitting the filter power unit to completely charge.
Three power fuses connect the filter power compo-
nents to the AC line. Very fast semiconductor power
fuses are utilized to quickly disconnect the transistor
module from the power source if a catastrophic failure
were to occur on the DC bus of the filter power unit.
The three phase inductor provides some impedance for
the filter to “work against”. It effectively limits the rate
of change in current at the input to the filter to a reason-
able level.
The Filter Power Unit is the most complicated power
component in the optional filter. Its purpose is to gen-
erate the harmonic currents required by the OSCD’s
AC-to-DC converter so that these harmonic currents
are not drawn from the AC line. The Filter Power Unit
is identical to the OSCD's Power Unit in the 351 Hp
drive, except for 2 less capacitors in the filter capacitor
“bank”, and a smaller transistor module and modified
gate driver board. The Harmonic Filter Gate Driver
board provides turn on and turn off commands as deter-
mined by the Harmonic Filter Logic board. “Bleeder”
resistors are mounted on the side of the Filter Power
Unit to provide a discharge path for the DC bus capaci-
tors.
Other sensors and boards are used to provide safe op-
eration of the harmonic filter. The transistor module
contains a temperature sensor that provides tempera-
ture information back to the Filter Logic Board. This
sensor protects the filter transistor module from over
temperature conditions. A Bus Isolator board is used to
ensure that the DC bus capacitors are properly charged
and the voltage is balanced. Two output current sensors

JOHNSON CONTROLS 15
SECTION 1 - GENERAL INFORMATION
FORM 160.00-O4
ISSUE DATE: 07/31/2019
1
are used to protect the filter against an over current or
an overload condition. Input current transformers sense
the input current drawn by the OSCD’s AC to DC con-
verter. The Line Voltage Isolation board provides AC
line voltage information to the Harmonic Filter Logic
board. This information is used to determine the proper
bus voltage value.
The “trap” filter is standard on all OSCD's that con-
tain an optional Harmonic Filter. The “trap” filter is
composed of a series of capacitors, inductors, and re-
sistors. The “trap” filter is used to reduce the effects
of the PWM switching frequency of the filter on the
power source.
DIFFERENCES BETWEEN THE G AND W
DESIGNS
Within the drive model number nomenclature there are
2 different letters for the design center of the drive. A
‘G’ for the design center is a drive that is designed to
the UL and CE requirements. A ‘W’ for the design cen-
ter is a drive that is designed to standards that govern
products built for the Asia market. The way the drive
functions, protects itself, and the motor are the same
for both designs. The ‘W’ design takes advantage of
local components, and local manufacturing. The cool-
ing system is the area where most of the changes occur
and only effect the 50 Hz application. The ‘W’ design
solves the problem of reduce cooling because of 50
Hz power by using a large cooling fan and a different
cooling pump. The cooling fan and pump require a 230
VAC 50 Hz source. This higher power source allows
the fan and pump to provide the same amount of cool-
ing as the 60 Hz application. The 230 VAC source is
provided by an additional voltage tap from the control
transformer. This new transformer provides the voltage
required for the 230 VAC and 120 VAC components.
DIFFERENCES FOR THE VSD AND LVD
MODEL DRIVES
The VSD model drives are designed so that the har-
monic filter system can be included in the drive enclo-
sure. The VSD model also contains the control wiring,
additional cooling capacity, and pre-charge resistors for
the harmonic filter system, regardless if the harmonic
filter system is installed or not. This process allowed
for an easier method to retrofit the harmonic filter sys-
tem later if the customer desired. The LVD model does
not contain any support for the harmonic filter system.
The enclosure size is reduced, and the harmonic filter
cannot be added as an option later. The function of the
drive is identical between the 2 designs.
OPTISPEED COMPRESSOR DRIVE CONTROL
SYSTEM OVERVIEW
The OSCD control system can be connected to a Mi-
crocomputer Control Center or to an OptiView Control
Center. Regardless of which control center is used each
component performs the same function.
The OSCD control system is composed of various
components located within both the Control Center
and the OSCD. Thus integrating the Control Center
with the OSCD. The OSCD system utilizes various
microprocessors, which are linked together through a
network of communications links.
The Control Center before 2005
The Control Center contains two boards that act upon
OSCD related information, the Microboard and the
Adaptive Capacity Control board (ACC). The ACC
board performs two major functions in the OSCD con-
trol system - (1) to act as a gateway for information
flow between the Control Center and the OSCD. (2) To
determine the optimum operating speed for maximum
chiller system efficiency.
The ACC board acts as an information gateway for all
data flowing between the OSCD and the Control Cen-
ter. The ACC board has a communication link to the
OSCD logic board, and one communication link from
the optional Harmonic Filter logic board. Once the
ACC board receives the information, the information
is then passed onto the Control Center via a software
communication link. The Microcomputer Control Cen-
ter communicates in a parallel fashion via two ribbon
cables connecting the ACC board to the Microboard.
The OptiView™ Control Center communicates
through communications port via a bi-directional serial
port via a three wire cable connecting the ACC board
to the Microboard.
In order to achieve the most efficient operation of a cen-
trifugal compressor, the speed of the compressor must
be reduced to match the “lift” or “head” of the load.
This “lift” or “head” is determined by the evaporator
and condenser refrigerant pressures. However, if the
compressor speed is reduced too much, the refrigerant
gas will flow backwards through the compressor wheel
causing the compressor to “surge”, an undesirable and
extremely inefficient operating condition. Thus there
exists one particular optimum operating speed (on the
“edge” of surge) for a given head, which provides the
optimum system efficiency.

JOHNSON CONTROLS
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FORM 160.00-O4
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SECTION 1 - GENERAL INFORMATION
The compressor’s inlet guide vanes, which are used
in fixed speed applications to control the amount of
refrigerant gas flowing through the compressor, are
controlled together with the compressor speed on an
OSCD chiller system to obtain the required chilled liq-
uid temperature while simultaneously requiring mini-
mum power from the AC line.
The ACC board automatically generates its own
“Adaptive” three-dimensional surge surface map while
the chiller system is in operation. This “Adaptive” op-
eration is accomplished through the use of a patented
surge detection algorithm. The novel surge detection
system utilizes pressure information obtained from the
chiller’s two pressure transducers or the OSCD’s in-
stantaneous power output to determine if the system
is in “surge”. Thus the adaptive system permits con-
struction of a customized compressor map for each in-
dividual chiller system. Benefits of this new adaptive
system include: (1) a customized compressor map for
each chiller which eliminates inefficient operation due
to the safety margin built into the previous designs 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 com-
pressor map if changes in refrigerant are implemented
at a later date.
The Control Center beginning in 2005
A major change in the control system took place in
2005. Several redesigns took place in the OptiView
panel and the OSCD. The redesign replaced micropro-
cessors that were becoming obsolete. This was a time
to take advantage of new components that were now
available. An additional communications port was add-
ed so that the communications between the microboard
and the OSCD logic board is faster. In the changes to
the microboard the function of the Adaptive Capacity
Board was placed into the microboard, and the ACC
board was longer needed in new production. The new
microboard is also compatible with the older designs
microboards used in the OptiView panel. The new
OSCD logic also added this new communication port,
but also retained all of the functions required to still
communicate with the ACC board.
OptiSpeed and Optional Harmonic Filter Logic
Control Boards
Within the enclosure of the VSD model drive, the
OSCD logic board and optional Harmonic Filter log-
ic board are interconnected via a 16-position ribbon
cable. This cable provides power for the Filter logic
board and a method of communications between the
two boards.
The OSCD Logic board performs numerous functions,
control of the OSCD’s cooling fans and pumps, when
to pre-charge the bus capacitors, and generates the
PWM.
The OSCD Logic board also determines shutdown
conditions by monitoring the three phases of motor
current, heatsink temperature, baseplate temperature,
internal ambient temperature, and the DC bus voltage.
The optional Harmonic Filter logic board determines
when to precharge the harmonic filter power unit, when
to switch the transistors in the harmonic filter power
unit, and collects data to determine power calculations.
This board also uses this data to determine shutdown
conditions.
Microcomputer Control Panel VSD Related
Keypad Functions
Refer to 160.00-M4 for related keypad functions.
Some of the displayed data in this form is different
from the 160.00-M1. Under the Options Key – the
following changes will be displayed:
VSD PHASE A INVERTER HEATSINK TEMP = ___°F.
VSD PHASE B INVERTER HEATSINK TEMP = ___°F.
VSD PHASE C INVERTER HEATSINK TEMP = ___°F.
These three temperature values are replaced with:
VSD BASEPLATE TEMP = ___°F
For the low HP model drives. The high HP model
drives will display 3 phases of Baseplate temperature.
When the Filter is present, the following data will
change from:
FILTER HEATSINK TEMP = ___°F.
This temperature data will now be called:
FILTER BASEPLATE TEMP = ___°F.

JOHNSON CONTROLS 17
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FORM 160.00-O4
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The names for the above data were changed because
the temperature sensor is now inside the transistor
module instead of the chill plate where the transistor
modules are mounted. This new sensor gives a better
indication of true temperature of the power electronics.
OptiView Control Panel VSD Functions
Refer to the specific OptiView™ Control Panel opera-
tions manual for detailed information. All of the OSCD
related information is contained under the Motor and
Compressor Screens.
VSD ADAPTIVE CAPACITY CONTROL
The YORK® OptiSpeed™ Compressor Drive utilizes
a different approach to speed reduction compared to
earlier variable speed products. There is no longer a
pre-programmed surge map – the YORK® adaptive
system experiments with the speed and vanes to find
the optimum speed for any given condition. It does not
always encounter a “Surge” in the process, but when
it does, the Adaptive Capacity Control (ACC) stores
into memory, the conditions surrounding the Surge,
and therefore remembers to avoid the stored operating
point anytime in the future.
Early versions of the ACC software required that the
drive always start and run up to full speed. ACC soft-
ware starting with version C.ACC.01.04 applies a new
slow ramp up of the drive speed. This new software
lowers the peak current demand from the drive during
start up, saves additional energy, and reduces the pos-
sibility of the chiller running in a stall condition.
The new software will quickly ramp the compressor
speed up to 1/2 speed, and then it takes 5 minutes to
ramp up to full speed. During this slow ramp up pe-
riod the vanes will open to meet the cooling demand.
If the leaving chilled liquid temperature is within +0.5
or lower of the leaving chilled liquid temperature
setpoint, then the drive speed will stop increasing the
RPM of the compressor motor, and start to search for a
surge map point. On extremely hot days the chiller may
surge during the slow ramp period. The new software
has a method to limit the surging. If 2 surges were to
occur during the slow ramp period, then the speed of
the drive will increase to full speed.
Now that the ACC function is provided by the mi-
croboard in the OptiView panel future control changes
will be covered by the operation manual for the chill-
er model of interest. All versions of software require
two conditions to be met for speed reduction to occur.
These two conditions are:
Setpoint Requirements
The leaving chilled liquid temperature must be
within +0.5 °F or lower from the leaving chilled
liquid temperature setpoint. A programmable val-
ue is now available through the OptiView panel
on software versions C.OPT.01.21.307 for the YK
chiller. This programmable value is not available
on the YT chiller. Speed reduction will not occur
until the leaving chilled liquid temperature reach-
es this range.
Stability Requirements
The leaving chilled liquid temperature must be
stable. Lack of stability will be indicative of the
vanes hunting, the leaving chilled liquid tempera-
ture varying, and the green LED on the ACC will
be on. Once the above conditions are met, the ACC
may begin to lower the speed of the compressor
motor 1/10 of a hertz at a time. As the ACC lowers
the speed, the leaving chilled liquid temperature
will begin to creep up. As this occurs, the con-
trol center will begin to open the vanes slightly,
just enough to maintain the leaving chilled liquid
temperature within +/- 0.5°F of the leaving chilled
liquid temperature setpoint. The ACC will contin-
ue to lower speed, with the leaving chilled liquid
temperature control in turn driving the vanes to
a more open position. This process will continue
until one of three following situations occur. This
setting is no longer available after software ver-
sion C.OPT.01.21.307 for the YK chiller.
Full Open Vane Operation
Once the vanes reach the full open position, the ACC
knows it can no longer reduce speed and maintain the
leaving chilled liquid temperature setpoint. The ACC
will maintain operation at this point, with the vanes full
open, and the speed at the last point reached when the
vanes hit 100%. If there is an increase in load while at
this point, the ACC will increase speed until the vanes
are closed to 95% of open. The ACC will then be al-
lowed to continue to reduce speed again.
Effects of Surge
If in the process of reducing speed and opening vanes
the compressor should surge, the ACC will boost the
speed up by 0.8 Hz. The ACC will store in memory a
value that represents the ratio of condenser pressure to
evaporator pressure, the vane position, and the speed of
the drive. The ratio of condenser pressure to evaporator
pressure is displayed as Delta P/P on the Control Panel.

JOHNSON CONTROLS
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FORM 160.00-O4
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SECTION 1 - GENERAL INFORMATION
The ACC will then know not to reduce speed this low
again, if the same delta pressure, and the vane posi-
tion conditions are encounter again in the future. As
the chiller encounters various conditions, which result
in surge, it will store more points, and eventually this
storing of points creates a “Surge Map”. Surge may be
detected in two ways, by monitoring the pressure dif-
ferential across the compressor, or by monitoring the
compressor motor current. Either detection will light
the Red LED on the ACC, indicating a surge was de-
tected. The chiller may surge 6 to 8 times before the
ACC can raise the speed enough to get the chiller back
out of surge. Each surge is counted on the surge coun-
ter, which may be viewed on the control center. This
surge counter will always display the total number of
surges encountered by the chiller as determined by the
ACC. Surging which occurs at fixed speed will incre-
ment the surge counter as well, but only surges that
occur when speed reduction is possible are recorded in
the surge map.
Drive Not Reducing Speed
The ACC may begin the process of reducing speed, but
may stop speed reduction if instability is encountered.
This is the same instability discussed as one of the two
conditions which must be met to begin reducing speed
initially (See “Stability Requirements”). Once the sys-
tem again becomes unstable, no additional speed re-
duction can occur.
The most common causes for instability are:
• High Condenser liquid temperature.
• Dirty Condenser tubes.
• Chillers with very light loads.
• Rapid changes to chilled or condenser liquid ow.
• Valves on air-handler coils closing rapidly caus-
ing changes in heat-load.
• Extremely short chilled liquid loop.
• Parallel chiller with poor control is causing tem-
perature variations.
• Parallel Chiller with poor control of chilled or
condenser water ows.
• Improper evaporator refrigerant level.
If you experience a problem with an OSCD not re-
ducing speed at all, make certain the system is not
in manual speed control, or locked into fixed speed.
Either situation will cause the chiller to maintain full
speed. If the OSCD is reducing speed, but not running
as slow as you expect it should, it is likely because it
is either in an unstable condition, or running just above
a mapped surge point. As described above, the chiller
must achieve stability, which is evidenced by the Green
LED being extinguished, before speed reduction will
commence. Instability will cause the Green LED to be
illuminated.
Stability Limit Adjustment
Stability Limit Adjustment allows the system to prop-
erly function with larger amounts of temperature insta-
bility. Consult YORK Service to make this adjustment.
Surge Margin Adjustment
Surge Margin Adjustment allows the Service Techni-
cian to increase the speed of the drive for all mapped
surge points. This parameter is rarely used, and it de-
creases the efficiency of the OSCD chiller system.
The ACC board is no longer in production. The func-
tions of theACC board were transferred to the OptiView
panel in 2008 with software version C.OPT.01.19.307
and the 031-02430-xxx board.

JOHNSON CONTROLS 19
FORM 160.00-O4
ISSUE DATE: 07/31/2019
2
FIGURE 1 - OPTISPEED SYSTEM ARCHITECTURE
(MODEL VSD 351 WITHOUT HARMONIC FILTER SHOWN, SIMILAR TO 270, 292, 424 MODELS)
INPUT
BREAKER
CONTROL
TRANSFORMER
INDUCTOR
COOLING
FANS
COOLING
COIL
LD13164
SECTION 2 - OPTISPEED COMPRESSOR DRIVE DETAILS

JOHNSON CONTROLS
20
FORM 160.00-O4
ISSUE DATE: 07/31/2019
SECTION 2 - OPTISPEED COMPRESSOR DRIVE DETAILS
FIGURE 1 - OPTISPEED SYSTEM ARCHITECTURE
(MODEL VSD 351 WITHOUT HARMONIC FILTER SHOWN, SIMILAR TO 270, 292, 424 MODELS)
(CONT'D)
COOLING
FANS
COOLING
COIL
GATE
DRIVER
BOARD
IGBT DC BUS
ISOLATOR
BOARD
SCR/DIODE
MODULE
SCR
TRIGGER
BOARD LD13165