McQuay RVSS14 User manual

Installation, Operation and Maintenance Manual IOMM Starter
Group: Chiller
Part Number: 331375501
Effective: Sept. 2005
Supercedes: New
Starters for Centrifugal Chillers
Low Voltage, Solid State and Wye-Delta
Medium/High Voltage, Solid State and Across-the-Line

2IOMM Starter
Table of Contents
General....................................................................................................................3
Variable Frequency Drives............................................................................................................4
Basic Electrical Terms...................................................................................................................4
Installation..............................................................................................................5
Mounting Arrangements................................................................................................................5
Receiving and Setting....................................................................................................................6
Location and Mounting.................................................................................................................6
Power Wiring .........................................................................................................8
Connection Sizes.........................................................................................................................10
Control Wiring.....................................................................................................13
Low Voltage Starters...................................................................................................................14
Medium/high Voltage Starters.....................................................................................................15
Startup ..................................................................................................................18
Low Voltage Solid State (LVSS).................................................................................................18
Low Voltage Wye-Delta (LVYD .................................................................................................21
Medium/High Voltage, Solid State..............................................................................................24
Operation, Low Voltage Starters, 200 – 600 Volts.............................................27
Introduction.................................................................................................................................27
Viewing Data...............................................................................................................................27
Changing Parameters...................................................................................................................32
Fault Code Troubleshooting Chart..............................................................................................40
General Troubleshooting Chart...................................................................................................48
Operation, Medium/High Voltage Starters, 2300V – 7.2KV............................52
Introduction.................................................................................................................................52
Viewing Data...............................................................................................................................52
Changing Parameters...................................................................................................................53
Quick Start ..................................................................................................................................55
Troubleshooting ..........................................................................................................................57
Fault/Log Codes..........................................................................................................................59
LED Diagnostics.........................................................................................................................62
Maintenance.........................................................................................................63
Index of Figures & Tables...................................................................................65
"McQuay" is a registered trademark of McQuay International
©2005 McQuay International
"Illustrations and data cover McQuay International products at the time of publication and we reserve the right to
make changes in design and construction at anytime without notice".

IOMM Starter 3
General
These starters are completely automatic and require no operator intervention (other than
clearing and resetting faults) to perform their function of providing a controlled connection
of the compressor motor to the power supply.
The Wye-Delta and solid-state starters have many similar software characteristics and are
discussed together in their operating section. However, some parameters and data are
different. Where this occurs, separate tables and figures are provided.
The low voltage (200-600 volts) starters are characterized by their control software, known
as “D3 Control”. Certain electrical operating data for these low voltage starters is
transmitted to the chiller and can be viewed on the operator touch screen if the “Full
Metering Option” has been ordered. See page 27 for details.
Medium and high voltage (2300-7200 volts) starters share common software known as
“Micro II Control”, not to be confused with the McQuay MicroTech II™chiller control
system.
Figure 1, Wye-Delta Starter
LED Display
Incomin
g
Lu
g
s
Sur
g
e Ca
p
acito
r
Terminal Strip
D3 Controller
Control Transformer and Fuses
Contactors
Transition Resistors

4IOMM Starter
Figure 2, Solid State Starter, Wall Mounted
Variable Frequency Drives
While known and specified for their ability to control compressor motor speed for
efficiency enhancement, VFDs also perform starting and motor protection functions. They
are only available for 3/60/460-480 service.
VFDs are available only from McQuay and when purchased as part of the original chiller
purchase. Installation and operation are covered in McQuay manual IOMM VFD.
Basic Electrical Terms
Locked rotor amps (LRA): The amount of current that a specific motor will draw at start-
up, when full voltage is applied across the line. The LRA may be 6 to 8 times FLA, or
possibly higher in some cases.
Inrush current: The amount of current that a specific motor and starter combination will
draw during start-up. Normal inrush current will be substantially less than LRA for all
starter types, except for across-the-line starters.
Full load amps (FLA): The maximum amps the motor is designed for.
Rated load amps (RLA): Actual amperage that the motor draws for a specific application.
Centrifugal compressor motors operate at a RLA significantly below their maximum full
load amps. RLA is used to determine electrical component sizing such as wire size and
disconnect switches.
Starting torque: Minimum torque required to begin the motor’s rotation.
Bypass contactor: Contactors that bypass auto-transformers, reactors, or SCRs, and allow
full power to reach the motor directly.
Terminal Strip
Disconnect Switch
Primary Control Circuit
Fuses
Control Transformer
SCRs (Behind)
D3 Controller
Bypass Contactor
LED Display

IOMM Starter 5
Interrupting capacity: The maximum fault current that a circuit breaker or fused
disconnect can successfully interrupt. As the rating increases, the construction becomes
heavier duty. For disconnect switches with fuses, the rating is based on 0 to 600 volts.
For circuit breakers, the voltage and amperage relationship is considered with interrupting
capacity decreasing as voltage increases.
Withstand rating: There is a period of time that the short circuit current passes to the
shorted circuit before the protection device can open. This time can be as long as 0.020
seconds (one cycle). The withstand rating of a starter is the maximum short circuit current
that it can pass safely without emitting sparks or debris.
Phase amps: The current draw inside the delta connection of a wye-delta motor winding.
It is equal to 0.577 x RLAof the motor for a specific load.
Open transition: A reduced voltage starter characteristic occurring when the motor is
temporarily disconnected from power at the time the starter changes from the starting
mode to the final running mode. A second smaller inrush spike will occur. McQuay does
not recommend use of this type of starter.
Closed transition: A reduced voltage starter characteristic when the motor is NOT
temporarily disconnected from the line during the transition from starting mode to
operating mode. The electrical load is transferred to resistors during the transition phase
and the second inrush spike is suppressed.
Installation
Mounting Arrangements
Low voltage starters can be factory-mounted with power and control wiring factory-
installed or they can be free-standing, requiring field mounting remote from the unit and
field-wiring of power and control wiring. Because of dimension restrictions for shipping,
some “factory-mounted” starters for large chillers are shipped separate from the unit.
Mounting supports are on the unit and preassembled cable kits are provided. Mounting
and wiring on site are the customer’s responsibility and can be subcontracted to McQuay
Factory Service if desired.
Medium voltage starters and some size low voltage starters on WSC 100 through 126 are
only available for free-standing applications.
Low voltage starters can be supplied in several different mounting arrangements
depending on the chiller size and starter type. See Table 1 for available arrangements.
• Factory-Mounted (optional): The starter is mounted on the chiller unit with the back of
the starter against the motor terminal box and wired directly to the motor. This
arrangement is only available on WSC/WDC 063, 079, or 087 units (cover
photograph).
On models WSC/WDC 048/050, the starter is factory-mounted on the front of the
chiller unit and connected to the motor with conduit and cable.
• Free-standing (standard): Floor-mounted, separate from the chiller unit, and field
wired to the compressor motor. This is available on all units and is the only starter
arrangement available for WDC/WCC 100 and 126 dual compressor units.
• Brackets and cable (optional): Starters for WSC 100 and 126 single compressor units
may be shipped separately from the chiller unit and furnished with mounting brackets
and interconnecting cables for field mounting and connection by others. This option
must be clearly specified when chillers are ordered since brackets are welded onto the
evaporator during its construction.

6IOMM Starter
Table 1, Starter/VFD Mounting Arrangements
Size Factory-
Mounted Free- Standing Brackets & Cables
WSC/WDC 050 X X
WSC/WDC 063 X X
WSC/WDC 079 X X
WSC/WDC 087 X X
WSC 100 - 126 X X
WDC 100 - 126 X
WCC 100 - 126 X
Receiving and Setting
Since factory-mounted starters are mounted and wired at the factory, this section will only
apply to free-standing units.
The unit should be inspected immediately after receipt for possible damage.
All McQuay centrifugal starters are shipped FOB factory and all claims for handling and
shipping damage are the responsibility of the consignee.
Extreme care must be used when rigging the starter to prevent damage. See the certified
dimension drawings included in the job submittal for the center of gravity of the unit.
Consult the local McQuay sales office for assistance if the drawings are not available.
The starter can be lifted by fastening the rigging hooks to the four lifting eyes located on the
top of the unit.
Location and Mounting
Clearance
The starter must be mounted on a level concrete or steel base and must be located to provide
adequate service. Local codes or the National Electric Code (NEC) can require more
clearance in and around electrical components and must be checked.
Mounting
Make sure that the floor or structural support is adequate to support the full weight of the
unit.
Standard NEMA 1 and NEMA 12 starters must be installed indoors in an area that is not
exposed to direct water spray. Do not install in areas where the ambient temperature falls
below 32°F (0°C) or exceeds 104°F (40°C) enclosed, or 122°F (50°C) open unless this was
noted at the time of order placement and special precautions were taken to protect against
these abnormal temperatures.
Heatsink temperatures can run as high as 158°F (70°C) during normal operation. Do not
mount the starter in contact with any material that cannot accept this heat. The starter must be
mounted with the heat sink fins oriented vertically in an area that will not experience
excessive shock or vibration.
Ventilation Requirements
Provisions should be provided in the starter enclosure to ensure that the temperature inside
the enclosure never rises above 122°F (50°C) or the starter could be damaged or the life of
the starter could be reduced. As a general rule of thumb the following ventilation guidelines
should be followed. These values are for starters with bypass. Bypassed starters generally
do not require ventilation.

IOMM Starter 7
Safety Precautions
Electrical codes require that all equipment (starter, motor, operator station, etc.) be properly
grounded. An incoming disconnect must be locked open before wiring or servicing the starter,
motor, or other related equipment. The equipment must only be serviced by qualified
personnel fully familiar with the equipment.
The opening of the branch circuit protective device may be an indication that a fault current
has been interrupted. To reduce the risk of electrical shock, current carrying parts and other
components of the starter should be inspected and replaced if damaged.
Equipment is at line voltage when AC power is connected. Pressing the Stop push-button on
the chiller control panel does not remove AC mains potential. All phases must be
disconnected before it is safe to work on machinery or touch motor terminals and control
equipment parts.
Power Factor Capacitors, Surge Capacitors and Lightning Arrestors
These devices MUST NOT be used with solid state starters. The SCR’s in the starter will be
damaged by the di/dt levels created.
On wye-delta starters, they are connected between the starter and the motor.

8IOMM Starter
Power Wiring
Power wiring between the starter and the compressor motor terminals is field supplied and
installed on units with remote-mounted, free-standing starters. See the field wiring diagram
on page 16.
Wiring, fuse and wire size must be in accordance with the National Electric Code (NEC).
Standard NEMA motor starters require modification to meet McQuay specifications. Refer to
McQuay Specification R35999901.
CAUTION
Important: Voltage unbalance not to exceed 2% with a resultant current
unbalance of 6 to 10 times the voltage unbalance per NEMAMG-1, 1998
Standard. This is an important restriction that must be adhered to.
WARNING
Qualified and licensed electricians must perform wiring.
Shock hazard exists.
Refer to Figure 5 on page 16 for power wiring connections.
Power wiring to compressors must be in proper phase sequence. Motor rotation is set up for
clockwise rotation facing the lead end with phase sequence of 1-2-3. Care must be taken that
the proper phase sequence is carried through the starter to compressor. With the phase
sequence of 1-2-3 and L1 connected to T1 and T6, L2 connected to T2 and T4, and L3
connected to T3 and T5, rotation is proper. See diagram in terminal box cover.
The McQuay start-up technician will check the phase sequence. Note: Do not make final
connections to motor terminals until wiring has been checked and approved by a McQuay
technician.
CAUTION
Connections to terminals must be made with
copper lugs and copper wire.
Under no circumstances should a compressor be brought up to speed unless proper sequence
and rotation have been established. Serious damage can result if the compressor starts in the
wrong direction. Such damage is not covered by product warranty.

IOMM Starter 9
Motor Terminal Insulation
It is the installing contractor's responsibility to insulate the compressor motor terminals when
the unit voltage is 600 volts or greater, or in high humidity locations that could cause
condensation on the motor terminals that are at about 50°F (10°C). The required material is
shipped in as a kit (775123601) placed in the motor terminal box on all medium and high
voltage units. It can be ordered for high humidity applications.
This is to be done after the McQuay start-up technician has checked for proper phase sequence
and motor rotation.
Following this verification by the McQuay technician, the contractor should apply the
following items.
Materials required for 600+volts or high humidity:
1. Loctite®brand safety solvent (12 oz. package available as McQuay part number
350A263H72)
2. 3M™Co. Scotchfil brand electrical insulation putty (available in a 60-inch roll as
McQuay part number 350A263H81)
3. 3M Co. Scotchkote™brand electrical coating (available in a 15 oz. can with brush as
McQuay Part Number 350A263H16)
4. Vinyl plastic electrical tape
The above items are also available at most electrical supply outlets.
Application procedure:
1. Disconnect and lock out the power source to the compressor motor.
2. Using the safety solvent, clean the motor terminals, motor barrel adjacent to the
terminals, lead lugs, and electrical cables within the terminal 4OX to remove all dirt,
grime, moisture and oil.
3. Wrap the terminal with Scotchfil putty, filling in all irregularities. The final result
should be smooth and cylindrical.
4. Doing one terminal at a time, brush the Scotchkote coating on the motor barrel to a
distance of up to 1/2 in. around the terminal and on the wrapped terminal, the rubber
insulation next to the terminal, and the lug and cable for approximately 10 in. Wrap
additional Scotchfil insulation over the Scotchkote coating.
5. Tape the entire wrapped length with electrical tape to form a protective jacket.
6. Finally, brush on one more coat of Scotchkote coating to provide an extra moisture
barrier.
General Wiring Practice
Wire groups
Signal wiring refers to wires connected to the control terminals that are low voltage, below
15V.
• Shielded wire is required to prevent electrical noise interference from causing
improper operation or nuisance trips.
• Signal wire should be rated for at least 300V.
• Keep signal wire as far away as possible from control and power wiring.
Control wiring is wiring connected to the control terminal strip that carry 24V to 220V.
• Use only UL or CSA recognized wire.
• Use copper wire rated for 60/75°C.
• Power wiring to the motor must have the maximum possible separation from all other
wiring. Do not run control wiring in the same conduit; this separation reduces the
possibility of coupling electrical noise between circuits. Minimum spacing between
metallic conduits containing different wiring groups should be three inches (76 mm).
• Minimum spacing between different wiring groups should be six inches (152 mm).

10 IOMM Starter
• Wire runs outside of an enclosure should be run in metallic conduit or have
shielding/armor with equivalent attenuation.
• Different wire groups should cross at 90 degrees whenever power and control wiring
cross.
• Different wire groups should be run in separate conduits.
• Adhere to local electrical codes.
• The National Electrical Code and Canadian Electrical Code requires that an approved
circuit disconnecting device be installed in series with the incomingAC supply in a
location readily accessible to personnel installing or servicing this equipment. If a
disconnect switch is not supplied with the starter, one must be installed.
• Supply and motor wiring will usually enter and leave the enclosure from the top. Wire
connections can be determined to best suit specific installations. Wire runs should be
properly braced to handle both starting and fault currents. Size power cable per local
electrical codes. Long lengths of cable to the motor of over 150 feet must be de-rated.
BEFORE APPLYING MAIN POWER
The starter has been fully tested before leaving the factory to help a rapid and problem-
free start-up. Before applying power to the starter, consult the start-up checklist below.
1. Inspect starter and remove any foreign matter.
2. Inspect the starter for any shipping damage.
3. Ensure that all electrical connections are as per the system schematics supplied with
the starter and/or connection diagrams.
4. Ensure that all connections are properly tightened.
5. Test L to T resistance of each phase and ensure that it is greater than 50 kohms.
Reverse leads and test again.
6. Check that the gate to cathode resistance of each SCR is between 8 and 50 ohms.
7. Check the resistance of all power and motor leads to ground to ensure that there is no
foreign matter present or damage to the insulation which can short one or more of the
phases to ground.
8. Apply 120 Vac control voltage to the starter.
Connection Sizes
Low Voltage Solid State
Table 2, Solid State Connection Sizes, Power Block
Starter
Model No.
(Note 1)
Incoming
Connection to
Power Block
Outgoing
Connection Size
(Note 2)
RVSS14 2/C #6-300 0.5
RVSS17 2/C #6-300 0.5
RVSS20 2/C #6-300 0.5
RVSS27 2/C #6-300 0.5
RVSS34 2/C #6-300 0.5
RVSS41 2/C #6-300 0.5
RVSS47 2/C #6-350 0.5
RVSS57 4/C 1/0 - 750 0.5
RVSS67 4/C 1/0 - 750 0.5
RVSS82 4/C 1/0 - 750 0.5
RVSS96 4/C 1/0 - 750 0.5
RVSS2K 4/C 1/0 - 750 0.5
RVSS4K 4/C 1/0 - 750 0.5
NOTES:
1. Data is the same for unit-mounted
starters, RVST14, etc.
2. Outgoing are NEMA 1 hole pattern.
3. Outgoing connections are factory-
connected to the motor on factory-
mounted starters.
4. When connecting to a starter with
the standard power block, the
incoming connection size is
determined by the starter size as
listed in the above table.

IOMM Starter 11
Table 3, Solid State, Connection Sizes, Disconnect & Circuit Breaker
50/60 HZ
Max RLA Incoming Size Disc. Switch Incoming Size Circuit Breaker
74 #6- 350 #6- 350
93 #6- 350 #6- 350
148 #6- 350 #6- 350
163 #6- 350 #6- 350
185 2/C 3/0 - 500 2/C 3/0 - 500
296 2/C 3/0 - 500 2/C 3/0 - 500
444 3/C 1/0 - 500 3/C 1/0 - 500
593 4/C 250 - 500 4/C 250 - 500
889 5/C 300 - 600 5/C 300 - 600
1185 5/C 300 - 600 5/C 300 - 600
1481 5/C 300 - 600 5/C 300 - 600
NOTES:
1. For field wiring free-standing starters, the outgoing connection size is determined by
the starter size as listed under the “Outgoing Connection Size” column in Table 2.
Outgoing connections are factory-connected to the motor on factory-mounted starters.
2. When wiring to a starter (either factory-mounted or free-standing) with an optional
disconnect switch or circuit breaker, the incoming connection size is determined by the
device size as shown in the above table. For standard power block, the incoming
connections are as shown in Table 2.
Low Voltage Wye-Delta
Table 4, Wye-Delta Connection Sizes, Standard Power Block
Starter
Model No
(Note 1).
Incoming
Connection Size,
Power Block
Outgoing
Connection Size
(Note 2)
D3WD11 2/C #6 - 300 0.31
D3WD12 2/C #6 - 300 0.31
D3WD14 2/C #6 - 300 0.31
D3WD15 2/C #6 - 300 0.31
D3WD25 2/C #6 - 300 0.31
D3WD31 2/C #6 - 300 0.38
D3WD34 2/C #6 - 300 0.38
D3WD43 2/C #6 - 300 0.44
D3WD62 2/C #6 - 350 0.44
D3WD65 2/C #6 - 350 0.44
D3WD86 4/C 1/0 - 750 0.63
D3WD1K 4/C 1/0 - 750 0.63
D3WD2K 4/C 1/0 - 750 0.63
NOTES:
1. Data is the same for unit-mounted starters, D3WT11, etc.
2. Outgoing connection is NEMA 1 hole pattern, diameter in inches as shown.
3. Outgoing connections are factory-connected to the motor on factory-mounted starters.
4. When connecting to a power block, the connection size is determined by the starter size.

12 IOMM Starter
Table 5, Wye-Delta Connection Size, Disconnects & Circuit Breakers
50/60 HZ
Max RLA Incoming Size Disc. Switch Incoming Size Circuit Breaker
74 #6- 350 #6- 350
93 #6- 350 #6- 350
148 #6- 350 #6- 350
163 #6- 350 #6- 350
185 2/C 3/0 - 500 2/C 3/0 - 500
296 2/C 3/0 - 500 2/C 3/0 - 500
444 3/C 1/0 - 500 3/C 1/0 - 500
593 4/C 250 - 500 4/C 250 - 500
889 5/C 300 - 600 5/C 300 - 600
1185 5/C 300 - 600 5/C 300 - 600
1481 5/C 300 - 600 5/C 300 - 600
NOTES:
1. For field wiring free-standing starters, the outgoing connection size is determined by
the starter size as listed under the “Outgoing Connection Size” column in Table 2.
Outgoing lugs are factory-connected to the motor on factory-mounted starters.
2. When wiring to a starter (either factory-mounted or free-standing) with an optional
disconnect switch or circuit breaker, the incoming lug size is determined by the device
size as shown in the above table. For standard power block, the incoming connections
are as shown in Table 2.
Medium Voltage, Solid State, Across-the-Line
Incoming and outgoing connections are crimp-type connectors, standard bus tabs are
NEMA 2.
Compressor Motor Connections
Power wiring connections at the motor are “spark plug” type terminals with threaded
copper bar, sized per the following table.
Type/Size Comp. Size Terminal Size
Low Voltage to 275 A, to 575 V CE 050 0.375-16 UNC-2A, 0.94 in. long
Low Voltage to 750 A, to 575V CE 063-126 0.635-11 UNC-2A, 1.88 in. long
Med. Voltage to 275 A, to 4160 V CE 063-126 0.375-16 UNC-2A, 0.97 in. long
Hi Voltage to 275 A, to 7200 V CE 063-126 0.375-16 UNC-2A, 1.00 in. long

IOMM Starter 13
Control Wiring
Control wiring is required between the starter and the unit for three purposes:
1. Transmit start and stop commands from the unit to the starter.
2. Transmit electrical information concerning motor operation from the starter to the unit
control system.
3. Supply control power from the starter transformer to the unit control panels.
General Practice
Signal wiring refers to wires connected to the control terminals that are low voltage, below
15V.
• Shielded wire is required to prevent electrical noise interference from
causing improper operation or nuisance trips.
• Signal wire should be rated for at least 300V.
• Keep signal wire as far away as possible from control and power wiring.
Control wiring refers to wires connected to the control terminal strip that carry 24V to 220V.
• Use only UL or CSA recognized wire.
• Use copper wire rated for 60/75°C.
Control Power Wiring
Control power wiring for starters covered in this manual is shown on Figure 5 on page
16. Low voltage starters may have additional control wiring as shown on Figure 4 if the
optional full metering package is ordered with the unit.
The control circuit on the McQuay centrifugal packaged chiller is designed for 115-volts.
Control power can be supplied from three different sources:
• If the unit is supplied with a factory-mounted starter, the control circuit power supply
is factory-wired from a transformer located in the starter.
• A free-standing starter furnished by McQuay, or by the customer to McQuay
specifications, will have a control transformer in it and requires field wiring to
terminals in the compressor terminal box.
• Power can be supplied from a separate circuit and fused at 20 amps inductive load.
The control circuit disconnect switch must be tagged to prevent current interruption.
Other than for service work, the switch is to remain on at all times in order to
keep oil heaters operative and prevent refrigerant from diluting in oil.
DANGER
If a separate control power source is used, the following must be done to avoid
severe personal injury or death from electrical shock:
Place a notice on the unit that multiple power sources
are connected to the unit.
Place a notice on the main and control power disconnects that
another source of power to the unit exists.

14 IOMM Starter
Separate Power Source
Chiller control power usually comes from a control transformer located in the starter and
factory or field wired to the chiller control panel. In the event a separate transformer supplies
control voltage, it must be rated at 3 KVA, with an inrush rating of 12 KVA minimum at 80%
power factor and 95% secondary voltage. For control wire sizing, refer to NEC. Articles 215
and 310. In the absence of complete information to permit calculations, the voltage drop
should be physically measured.
Table 6, Control Power Line Sizing
Maximum Length, ft (m) Wire Size (AWG) Maximum Length, ft (m) Wire Size (AWG)
0 (0) to 50 (15.2) 12 120 (36.6) to 200 (61.0) 6
50 (15.2) to 75 (22.9) 10 200 (61.0) to 275 (83.8) 4
75 (22.9) to 120 (36.6) 8 275 (83.8) to 350 (106.7) 3
Notes:
1. Maximum length is the distance a conductor will traverse between the control power
source and the unit control panel.
2. Panel terminal connectors will accommodate up to number 10 AWG wire. Larger
conductors will require an intermediate junction box.
The Unit On/Off switch located in the Unit Control Panel should be turned to the "Off"
position any time compressor operation is not desired.
Low Voltage Starters
Control wiring for low voltage starters is per the wiring diagram on page 16. If the optional
“Full Metering Display” has been ordered, the following section will apply.
Wiring for Optional Remote D3 Display Figure 3, Starter Panel
Remote mounted low voltage wye-delta and solid state
starters require field wiring to activate the optional full
metering display on the chiller’s operator interface panel.
The wiring is from the D3 board in the starter to the
compressor controller and to the bias block; both located
in the compressor control panel. See Figure 4, Field
Wiring for Optional D3 .
The location of the connections in the starter are shown to
the right.
Wiring Connection on Starter for Optional Display

IOMM Starter 15
Figure 4, Field Wiring for Optional D3 Communication
NOTES.
1. See Figure 3 for Starter connection location.
2. The compressor controller serial card location is in the lower-center of the compressor
controller, under the operating buttons.
3. The bias block is located on the rail, just to the left of the compressor controller.
4. Note that the connections are (-) to (-), (+) to (+), and SCOM to GND, with a shield
connection on the starter terminal board.
Medium/high Voltage Starters
Control wiring for medium and high voltage solid state and across-the-line starters is per the
wiring diagram on page 16.

16 IOMM Starter
Figure 5, Control and Power Field Wiring
80
CP2
CP1
H
O
A
C4
H
A
O
C3
H
A
O
79
78
77
74
73
54
CF
86
EF
86
C
25
1
2
11
11
12
22
1
2
6
11
12
22
NOTE 2
NOTE 2
(115V) (24V)
25
55
70
H
A
O
H
A
O
H
O
A
C
H
O
A
C
H
O
A
C
C2
C1 T3-S
PE
L1
L2
CP2
CP1
24
23(5A)
24(5)
23
3
4
3
4
76
75
PE
85
86
81
84
A
82(NO)
83(NC)
POWER
EP2
EP1
L1 L2 L3
GND
T4 T5 T6
T1 T2 T3
T4 T5 T6T1 T2 T3
T1 T2 T3
T3T1 T2
UVW
T4 T3 T5T1 T6 T2
T1 T2 T3
T4 T3 T5T1 T6 T2
GND
LESS
THAN
30V
OR
24VAC
53
71
71
52
1-10 VDC
1-10 VDC
MI
C
R
O
TE
C
H
CO
NTR
O
L
BOX TERMINALS
* COOLING
TOWER
FOURTH
STAGE
STARTER
* COOLING
TOWER
THIRD
STAGE
STARTER
* COOLING
TOWER
SECONDH
STAGE
STARTER
* COOLING
TOWER
FIRST
STAGE
STARTER
COOLING TOWER
BYPASS VALVE
COOLING TOWER VFD
ALARM RELAY
(NOTE 4)
MICROTECH
COMPRESSOR CONTROL
BOX TERMINALS
CTB1
-LOAD-
COMPRESSOR
MOTOR
STARTER
(NOTE 1)
115 VAC
STARTER LOAD SIDE TERMINBALS
VFD
STARTER LOAD SIDE TERMINBALS
WYE-DELTA
STARTER LOAD SIDE TERMINBALS
SOLID STATE
STARTER LOAD SIDE TERMINBALS
MEDIUM AND HIGH VOLTAGE
COMPRESSOR TERMINALS
COMPRESSOR TERMINALS
COMPRESSOR TERMINALS
COMPRESSOR TERMINALS
NOTE 12
- FOR DC VOLTAGE AND 4-20 MA
CONNECTIONS (SEE NOTE 3)
- FOR DETAILS OF CONTROL REFER
TO UNIT CONTROL SCHEMATIC
330342101
- COMPRESSOR CONTROL
SCHEMATIC 330342201
- LEGEND: 330343001
* FIELD SUPPLIED ITEM
* NOTE 7
* NOTE 10
* NOTE 10
* NOTE 10
* NOTE 10
330387901-0A
COMMON
NEUTRAL
POWER
See notes on the following page.

IOMM Starter 17
NOTES for Wiring Diagram
1. Compressor motor starters are either factory-mounted and wired, or shipped separate
for field-mounting and wiring. If provided by others, starters must comply with McQuay
specification 359AB99. All line and load side power conductors must be copper.
2. If starters are freestanding, then field control wiring between the starter and the control
panel is required. Minimum wire size for 115 Vac is 12 GA for a maximum length of 50
feet. If greater than 50 feet, refer to McQuay for recommended wire size minimum.
Wire size for 24 Vac is 18 GA. All wiring to be installed as NEC Class 1 wiring system
and must be made with copper wire and copper lugs only. All 24 Vac wiring must be
run in separate conduit from 115 Vac wiring.
3. Main power wiring between starter and motor terminal is factory-installed when chillers
are supplied with unit-mounted starters.
4. For wye-delta, and solid state starters connected to six (6) terminal motors (low
voltage), the conductors between the starter and motor carry phase current and wire
size selection is based on 58 percent of the motor rated load amperes (RLA). Wiring
of free-standing starters must be in accordance with the NEC and connection to the
compressor motor terminals shall be made with copper wire and copper lugs only.
Main power wiring between the starter and motor terminals is factory-installed when
chillers are supplied with unit-mounted starters.
5. The “Full Metering” option will require some field wiring when free-standing starters are
used, as shown in Figure 4 on page 15.

18 IOMM Starter
Startup
General
The startup of McQuay centrifugal chillers, including the starters, is performed by McQuay
authorized and trained technicians. They review the starter connections, phase sequence, and
settings prior to starting the chiller.
Setting a freestanding starter and power and control wiring from it to the chiller is the
responsibility of the owner/contractor. See the installation and power and control wiring
sections of this manual before commencing installation.
In the rare instances where a starter is being replaced after the chiller has been in service,
McQuay service is not automatically involved but can be contracted to supervise the starter
installation.
For general information, brief startup instructions are included on the following pages.
Low Voltage Solid State (LVSS)
LED Display
• Located on the starter control board
• View parameters, messages and faults.
• Shows software revision on power up.
Programming
• Press PARAM to enter the menu and
then UP or DOWN to reach the desired
parameter.
• Press ENTER to show the present value
of the parameter.
• Press UP or DOWN to change the
parameter value.
• Press ENTER to store the new value or PARAM to abandon the change.
Quick Meters
• Press DOWN to display the motor thermal overload content.
• Press UP to display the incoming line phase order.
• Press ENTER to display the status meter.
Fault Log·
• Select P32 and press ENTER. The most recent fault will be displayed as “xFyy”
where x will be 1 to indicate the most recent fault is being displayed and yy is the
fault code.
• Press DOWN to view older faults. Up to 9 faults may be stored in the log.
Resetting a Fault·
• Press RESET to reset from a fault.Resetting Parameters·
• Press and hold PARAM and ENTER on power up to reset parameters to default
values.

IOMM Starter 19
Emergency Thermal Reset·
• Press RESET and DOWN to perform an emergency thermal reset.
Messages (LVSS)
No Line
Ready
Accelerating
Up to Speed
Run – Done with ramp but not yet
Up to Speed.
Decelerating
OverloadAlarm – The motor
overload level is between 90% and
100%.
Overload Fault – The motor
overload level has reached 100%.
Overload Lockout –A start is not
allowed until the motor overload
level cools below 60%.
Control Power Lockout –Astart is
not allowed because the control
power is too low.
xxx xxx = overload content. Press
DOWN to toggle.
xx xx = Alarm code. If the condition
persists, a fault will occur.
xx xx = Fault code. Press RESET to
clear.
Instantaneous Overcurrent – Press
RESET to clear.
Default – Flashes when parameter
defaults are loaded.
Default Meter Display (P13) (LVSS)
0: Status
1: Ave RMS Current
2: L1 RMS Current
3: L2 RMS Current
4: L3 RMS Current
5: Current Imbalance %
6: Ground Fault Current
7: Ave L-L Voltage RMS
8: L1-L2 Voltage RMS
9: L2-L3 Voltage RMS
10: L3-L1 Voltage RMS
11: Overload %
12: PF
13: KW
14: KVA
15: KWh
16: MWh
17: Phase Rotation
18: Line Frequency
19: Analog Input
Analog Output Function (P28) (LVSS)
0: OFF (no output)
1: Ave Current (0 – 200% RLA)
2: Ave Current (0 – 800% RLA)
3: Ave Voltage (0 – 750VAC)
4: Thermal Overload%
5: KW (0 - 10KW)
6: KW (0 – 100KW)
7: KW (0 – 1MW)
8: KW (0 – 10MW)
9: Analog Input
10: Output Voltage (% of FV)
11: Calibrate (full 100% output)
CT Burden Switch Settings (P1 and P23) (LVSS)
FLA in Amps Setting
864:1 CTs 2640:1 CTs 5760:1 CTs 8000:1 CTs SW1 SW2
24 to 42 73 to128 160 to 280 223 to 390 Off Off
42 to 50 128 to 151 280 to 330 390 to 465 Off On
50 to 108 151 to 330 330 to 720 465 to 1000 On Off
108 to 190 330 to 590 720 to 1280 1000 to 1800 On On
Parameters (LVSS)
DESCRIPTION Values DEFAULT
SET
TO:
P1 Motor FLA 1 to 9999 Amps 10
P2 Motor RLA 1 to 9999 Amps 10
P3 Motor Service Factor 1.00 to 1.99 1.08
P4 Motor Overload Class OFF, 1 to 40 10
P5 Initial Motor Current 50 to 400 %FLA 250
P6 Maximum Motor Current 100 to 800 %FLA 300
P7 Ramp Time 0 to 300 seconds 10
P8 UTS Time 1 to 900 seconds 15
P9 Stop Mode CoS: Coast
dcL: Voltage Decel CoS
P10 Decel Begin Level 100 to 0 %Volts 40
Continued on next page.

20 IOMM Starter
DESCRIPTION Values DEFAULT
SET
TO:
P11 Decel End Level 50 to 0 %Volts 20
P12 Decel Time 1 to 180 seconds 15
P13 Default Meter Display 0 to 19 1
P14 Overcurrent Trip Level OFF, 50 to 800 %RLA OFF
P15 Overcurrent Trip Delay
Time 0.1 to 90.0 seconds 2.0
P16 Rated RMS Voltage 100, 110, 120, 200, 208,
220, 230, 240, 350, 380,
400, 415, 440, 460, 480,
575, 600, 660, 1000 Volts
480
P17 Over Voltage Trip Level OFF, 1 to 40 % rated Volts 10
P18 Under Voltage Trip Level OFF, 1 to 40 % rated Volts 10
P19 Over/Under Voltage
Delay Time 0.1 to 90.0 seconds 1.0
P20 Current Imbalance Trip
Level 5 to 40 % 10
P21 Controlled Fault Stop OFF, On OFF
P22 Auto Fault Reset Time OFF, 1 to 120 seconds 60
P23 CT Ratio 72, 96, 144, 288, 864,
2640, 2880, 5760, 8000 2640
P24 Control Source TEr: Terminal
NEt: Network tEr
P25 Modbus Address 1 to 247 1
P26 Modbus Baud Rate 1.2, 2.4, 4.8, 9.6, 19.2 Kbps 19.2
P27 Modbus Timeout OFF, 1 to 120 seconds 3
P28 Analog Output Function 0 to 11 1
P29 Analog Output Span 1 to 125 % 100
P30 Analog Output Offset 0 to 99 % 0
P31 Passcode 0 to 9999 –
P32 Fault Log xFyy –
Fault/Alarm Codes (LVSS)
Description
Controlled
Stop Auto Reset
00 No fault - -
01 UTS Time Limit Expired Y Y
02 Motor Thermal Overload Trip Y N
10 Phase Rotation Error, not ABC N Y
12 Low Line Frequency N Y
13 High Line Frequency N Y
15 Input power not three phase N Y
21 Low Line L1-L2 Voltage Y Y
22 Low Line L2-L3 Voltage Y Y
23 Low Line L3-L1 Voltage Y Y
24 High Line L1-L2 Voltage Y Y
25 High Line L2-L3 Voltage Y Y
26 High Line L3-L1 Voltage Y Y
27 Phase Loss N Y
28 No Line Voltage N Y
30 I.O.C. (Instantaneous Overcurrent) N N
31 Overcurrent Y N
37 Current Imbalance Y Y
38 Ground Fault Y N
39 No Current at Run N Y
40 Shorted / Open SCR N N
41 Current While Stopped N N
47 Stack Protection Fault N Y
48 Bypass Contactor Fault (on STOP input) Y N
50 Control Power Low N Y
51 Current Sensor Offset Error - N
52 Burden Switch Error N N