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Engineering Bulletin
Starters, Drives, and Electrical Components
for CenTraVac™ Chillers
Models: CVHE, CVHF , CVHG, CDHF , CDHG
Only qualified personnel should install and service the equipment. The installation, starting up, and
servicing of heating, ventilating, and air-conditioning equipment can be hazardous and requires specific
knowledge and training. Improperly installed, adjusted or altered equipment by an unqualified person could
result in death or serious injury. When working on the equipment, observe all precautions in the literature
and on the tags, stickers, and labels that are attached to the equipment.
December 2011
SAFETY WARNING
CTV-PRB004-EN
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Table of Contents
Related Manuals for Trane Starters
Summary of Contents for Trane Starters
- Page 1 Engineering Bulletin Starters, Drives, and Electrical Components for CenTraVac™ Chillers Models: CVHE, CVHF , CVHG, CDHF , CDHG SAFETY WARNING Only qualified personnel should install and service the equipment. The installation, starting up, and servicing of heating, ventilating, and air-conditioning equipment can be hazardous and requires specific knowledge and training.
- Page 2 CFCs such as HCFCs and HFCs. Responsible Refrigerant Practices! Trane believes that responsible refrigerant practices are important to the environment, our customers, and the air conditioning industry. All technicians who handle refrigerants must be certified.The Federal Clean Air Act (Section 608) sets forth the requirements for handling, reclaiming, recovering and recycling of certain refrigerants and the equipment that is used in these service procedures.
- Page 3 Adaptive Frequency, CenTraVac, Duplex,TOPSS,Tracer AdaptiView,Tracer Summit,Trane, and the Trane logo are trademarks or registered trademarks ofTrane in the United States and other countries.Trane is a business of Ingersoll Rand. All trademarks referenced in this document are the trademarks of their respective owners.
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Page 4: Table Of Contents
......10 Standard Components of Trane Starters ......10 Chiller Selection Report . - Page 5 Industrial-Grade Starters ........
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Page 6: Introduction
Field connection diagrams are also available on the website. All unit-mounted starters are designed for top-entry line power only. Remote starters are typically designed for top-entry line power and a bottom exit for load wires.The medium-voltage starter submittals show conduit space for alternate wiring options. -
Page 7: About Starters
The second function of the starter is to keep the initial current inrush below a specified level.Third, the starter communicates with the unit controller to coordinate motor protection. Starters can be as simple or as complex as necessary to meet various engineering specifications and/or customer needs. A variable-speed drive can provide starter functions, among other things (see “Low Voltage—Unit-Mounted Adaptive Frequency Drive, ”... -
Page 8: Motor Types And Voltage Classes
1,700 amps. Medium voltage has two main voltage groups. One ranging from 2,300 to 6,600 volts and the other ranging from 10,000 to 13,800 volts. Starters in this class have sizes up to 360 amps and 94 amps respectively. - Page 9 The ceramic insulators combined with the larger spacing between the motor terminals help prevent electrical arcing. Higher voltage motors and starters are being used in large chiller plants where incoming line power makes 10–13.8 kV accessible. In some cases, higher voltage chillers allow for the elimination of electrical components with their associated space requirements and energy losses.
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Page 10: Chiller Selection And Electrical Specification
A terminal block for line power connection is standard. Load-side lugs are standard for remote ® starters.The lug sizes and configuration are shown on the submittal drawing.TheTrane has a circuit breaker as standard. Medium-voltage starters have provisions for a bolted connection. Chiller Selection Report The following terms are found on a typicalTOPSS product report. - Page 11 Chiller Selection and Electrical Specification F. Minimum circuit ampacity (MCA). This term appears on the chiller nameplate and is used by the electrical engineer to determine the size and number of conductors needed to bring power to the starter. 4000 MCA = 1.25 x (Primary RLA [incoming line])+ volts motor...
- Page 12 Chiller Selection and Electrical Specification Figure 4. Excerpt from chiller selection report CTV-PRB004-EN...
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Page 13: Motor Protection
(d) For this option, add one or two sets (three RTDs per set) of 100-ohm platinum RTDs to the motor. Contact La Crosse Field Sales Support. (e) Under/over phase-voltage sensors include volts per phase, kW, power factor, kWh, and under/overvoltage. A required pick on medium-voltage starters. -
Page 14: Overload Protection
(a) The MP 3000 features Intel-I-Trip overload protection, enhanced custom trip curve development, UL 1053 ground fault, and advanced data logging and diagnostics. (b) Under/over phase-voltage sensors include volts per phase, kW, power factor, kWh, and under/overvoltage. A required pick on medium-voltage starters. Overload protection Overload or overcurrent protection shields the motor from small levels of overcurrent ranging from 107 to 140 percent of the primary RLA of the chiller. - Page 15 Motor Protection Figure 5. Tracer AdaptiView chiller controller overload time-to-trip curves Nominal Overload Trip Minimum Time (sec) Maximum % Run-Load Amps Overload situations, left unchecked by protection, can cause excessive motor heat, that can permanently damage the windings and lead to motor failure.The time until motor damage depends mainly on the magnitude of the overcurrent and has an inverse time versus current relationship.The greater the overcurrent, the less time it takes to cause motor damage.
- Page 16 Motor Protection Phase failure/loss protection The chiller will shut down if any of the three-phases of current feeding the motor drop below 10 percent RLA for 2.5 seconds. Phase imbalance protection Based on an average of the three phases of current, the ultimate phase-imbalance trip point is 30 percent.The RLA of the motor can be derated depending on the percent of this imbalance.The phase-imbalance trip point varies based on the motor load.
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Page 17: Low-Voltage Starter Types
AFD is appropriate for a specific application and location. Unit or remote mounted? Unit-mounted starters can save on installed cost and space, and they can be tested in the factory and shipped on the chiller in a NEMA 1 enclosure. Remote-mounted starters provide more options for multiple starter lineups, and may be chosen in order to implement some of the industrial starter options such as high-fault and NEMA 12/3R. -
Page 18: Low Voltage-Wye-Delta
Low Voltage—Wye-Delta Wye-Delta Starters One of the most common starters in the industry is the wye/star-delta. It is an electromechanical starter initially set up in a “wye” or “star” configuration, then it transitions to a “delta” configuration during the starting sequence.To illustrate a typical starting sequence using a generic (non-Trane) schematic, refer to Figure 7, p. - Page 19 Low-Voltage Starter Types Figure 7. Simplified wye-delta wiring schematic LINE VOLTAGE WYE-DELTA STARTER WIRING MOTOR START- STOP TRANSITION Starting sequence 1. The “start” signal from the CenTraVac controller energizes the pilot relay (PR). 2. The PR contacts close to energize the star contactor (S). 3.
- Page 20 Low-Voltage Starter Types The one-door remote-mounted starter size is generally used for 155- to 606-amp starters with no disconnect.The two-door size is used for 640- to 1,700-amp starters with no disconnect.The three- door size is used for 1,385- to 1,700-amps when disconnects are included.
- Page 21 Low-Voltage Starter Types Figure 12. Unit-mounted, wye-delta starter 1. Top-entry power only 2. 4 kVA control-power transformer 3. Circuit breaker (optional) 4. Transition resistors Standard features • Unit or floor mounted • Control-power transformer • Padlock tab for additional locking of the starter door •...
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Page 22: Low Voltage-Solid-State
An SCR will conduct current in one direction only when a control signal (gate signal) is applied. Because solid-state starters use alternating current (AC), two SCRs per phase are connected in parallel, opposing each other so that current may flow in both directions. - Page 23 Padlock tab for additional locking of starter door • Line-side connection terminal block/main lug only • UL and CUL certified Dimensions Typical dimensions for unit- or remote-mounted solid-state starters are shown in Figure 15. Always consult the submittal drawings for as-built dimensions. Figure 15. Solid-state dimensions 60"...
- Page 24 Low-Voltage Starter Types Figure 16. Unit-mounted, solid-state starter 1. Top-entry line power 2. Intelligent technology (IT) controller 3. Starter control board 4. Potential transformers 5. 4 kVA control-power transformer Environmental specification • Designed, developed, and tested in accordance with UL 508 •...
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Page 25: Low Voltage-Unit-Mounted Adaptive Frequency Drive
“pulse” in PWM. Starting sequence Trane AFDs are programmed to start the compressor motor using low frequency and low voltage, thereby minimizing the inrush current.The motor is then brought up to speed by gradually increasing both frequency and voltage at the same time.Thus, current and torque are much lower during startup and motor acceleration than the high current, high torque associated with across- the-line or even reduced-voltage starters;... - Page 26 The AFD is rated by output current and is limited to a maximum of 100-percent continuous RLA ® (rated-load amps) by theTrane chiller unit controller. A 100-percent output current capability results in 100-percent torque generated by the motor. Figure 18. Trane AFD 1. Pre-charge contactor 2. Inductor (behind the panel) 3. Adjustable-speed drive (inverter) 4.
- Page 27 Low-Voltage Starter Types Environmental specification • 32°F to 104°F (0°C to 40°C) operating ambient temperature. • Altitude to 3,300 feet (1,000 m), amperage derate of 1 percent per every 300 feet above 3,300 feet. • Humidity, 95 percent non-condensing. Dimensions Typical dimensions for the unit-mounted Adaptive Frequency Drive are shown in Figure 19 Figure...
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Page 28: Low Voltage-Remote-Mounted Adaptive Frequency Drive
Low Voltage—Remote-Mounted Adaptive Frequency Drive Depending on the application,Trane also offers a remote free standing Adaptive Frequency Drive (AFD).The remote AFD comes as a complete, free-standing package that includes the necessary controls, control power and programming needed for operation. - Page 29 Low-Voltage Starter Types Inverter IGBTs. Use the pulse width modulation (pwM) method to convert the DC voltage from the capacitor bank into a synthesized output AC voltage that controls both the voltage and frequency applied to the motor Figure 21. Front view, remote-mounted AFD Features The standard design features for the AFD include: •...
- Page 30 Low-Voltage Starter Types Environmental specification • Operating temperature: 32°F to 104°F (0°C to 40°C). • Storage temperature: -4°F to 149°F (-20°C to 65°C). • Humidity: 95 percent non-condensing. • Maximum elevation: 3280 ft (1000 m) rated output current. • Derate 4 percent/3280 ft over rated altitudes up to 9840 ft (3000 m). Dimensions Table 6 provides some basic reference dimensions and weights for the remote AFD.
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Page 31: Medium-Voltage Starter Types (2,300-6,600 Volts)
One question often asked is: “Which is better, full voltage or reduced voltage?” Because medium- voltage starters by nature use less current than low voltage, and therefore have significantly less current inrush. Across-the-line medium-voltage starters are more commonly used; however, in certain applications reduced voltage will be used to minimize starting strain on the electrical system. -
Page 32: Medium Voltage-Across-The-Line (2.3-6.6 Kv)
Medium-Voltage Starter Types (2,300–6,600 Volts) Other options for remote-mounted starters are available in the Enhanced Electrical Protection Package (see “Industrial-Grade Starters, ” p. 63.) NEC 2005 changes for medium-voltage (2,300–6,600 volt) wire NEC code for 2005 requires that medium-voltage cable is shielded.This affects the power wire selection and connection provisions to the chiller, and between the chiller and starter when it is remote mounted. - Page 33 Medium-Voltage Starter Types (2,300–6,600 Volts) Figure 23. Simplified across-the-line wiring diagram LINE VOLTAGE ACROSS-THE-LINE STARTER WIRING MOTOR START- STOP Figure 24. Unit-mounted, across-the-line starter dimensions Top Hat 9.13" 27" 60" 26.2" 40" 20" 38" Standard features • Control-power transformer • Primary and secondary current transformers (CTs) •...
- Page 34 Non-operating ambient temperature range -40°F to 158°F (-40°C to 70°C) • Voltage utilization range ±10 percent Dimensions Typical dimensions for unit- and remote-mounted across-the-line starters are shown in Figure 24, p. 33 Figure 25, p. 34. Always consult the submittal drawings for as-built dimensions.
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Page 35: Medium Voltage-Primary Reactor (2.3-6.6 Kv)
Medium Voltage—Primary Reactor (2.3–6.6 kV) Primary Reactor Starter (2,300–6,600 volts) One of the most common starters in the industry is the primary reactor.To illustrate a typical starting sequence using a generic (non-Trane) schematic, refer to Figure 27, p. 36 and the starting sequence below. - Page 36 Non-operating ambient temperature range -40°F to 158°F (-40°C to 70°C) • Voltage utilization range ±10% Dimensions Typical dimensions for remote-mounted primary reactor starters are shown in Figure 28, p. Unit-mounted primary reactor starter dimensions are shown in Figure 29, p.
- Page 37 Medium-Voltage Starter Types (2,300–6,600 Volts) Figure 28. Remote-mounted, reduced-voltage starter dimensions 80" 30" 72" Figure 29. Reduced-voltage, unit-mounted starter dimensions Reduced-Voltage Top Hat Section (mounted 9.13" on the condenser) 27" 60" 26.2" 40" 20" 38" CTV-PRB004-EN...
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Page 38: Medium Voltage-Autotransformer (2.3-6.6 Kv)
Figure 30. CenTraVac with a reduced-voltage autotransformer starter (CH530 unit controller) Medium Voltage—Autotransformer (2.3–6.6 kV) Autotransformer Starter (2,300–6,600 volts) Another medium-voltage starter type is the autotransformer.To illustrate a typical starting sequence using a generic (non-Trane) schematic, refer to Figure 31, p. 39 and the starting sequence below. - Page 39 • Potential transformers (PTs) • Grounding provisions • Bolted line-power connections • Bolted load-side connections for remote starters • Standard motor protection Environmental specification • Designed, developed, and tested in accordance with UL 347 • NEMA 1 enclosure as standard •...
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Page 40: Unit-Mounted Starter Top Hat-Nec 2005 Code Requirement
AutoTransformer, as does the relative complexity, and size.These starters are considered simple to begin with in comparison to solid state starters; however, we always want to use the simplest design if the performance (inrush level) meets the requirements of the application.This is why the X-Line type is often used at this voltage, because the amps are generally low to begin with based on the voltage class (i.e., 4,160 volts).Trane has shipped thousands of chillers and starters with... - Page 41 Medium-Voltage Starter Types (2,300–6,600 Volts) Figure 32. Top Hat placement for shipment and installation Sheet Metal “Top Hat” Section (allows space for shielded cable/stress cones—field provided) Stowed for Shipment Installed for Stress Cones CTV-PRB004-EN...
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Page 42: Medium Voltage-Remote-Mounted Adaptive Frequency Drive
Medium-Voltage Starter Types (2,300–6,600 Volts) Medium Voltage—Remote-Mounted Adaptive Frequency Drive TheTrane AFD is a remote-mounted air-cooled, microprocessor based pulse width modulation PWM design.The AFD use a “direct to drive” design that connects the power supply directly to the medium voltage drive with out the use of an isolation transformer.The AFD is a current source inverter that uses Symmetrical Gate CommutatedThyristors (SGCTs) power semi-conductor switches in both the rectifier and inverter sections.The active front end rectifier and common mode choke blocks any common mode voltages, smooths the DC current, and mitigates the motor neutral... -
Page 43: Chiller Unit Control Features For The Afd
Medium-Voltage Starter Types (2,300–6,600 Volts) • Displacement power factor is 0.96 at all loads. • Efficiency is 97.7 percent at rated load, 60 Hz. • Soft-start; linear acceleration; coast to stop. • All control circuit voltages are physically and electrically isolated from the power circuit voltage. - Page 44 Medium-Voltage Starter Types (2,300–6,600 Volts) The AFD is designed for a maximum operating temperature of 104°F . However, optimal operation and design life will be experienced if the ambient temperatures are kept well below this maximum. The maximum AFD heat rejection is listed on the AFD submittal drawing in this package. Additional equipment room cooling provisions may be required.
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Page 45: Medium-Voltage Starter Types (10,000-13,800 Volts)
Note: UL certification of these starters is not available due to AC voltage ranges exceeding 7,200 volts as specified in UL Standard 347.This includes all chiller starter manufacturers selling 10–13.8 kV refrigeration equipment. - Page 46 Medium-Voltage Starter Types (10,000–13,800 Volts) Figure 34. Remote-mounted, across-the-line dimensions MAIN BUS 95" INCOMING LOW-VOLTAGE LINE SECTION 36" 60" Figure 35. Remote-mounted, 11-kV, across-the-line starter 1. Current-limiting power fuses 2. Isolation switch (provision for one lock) 3. Control-power transformer 4. Vacuum contactors CTV-PRB004-EN...
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Page 47: Medium Voltage-Primary Reactor (10-13.8 Kv)
Bolted load-side connections for remote starters • Standard motor protection Dimensions Typical dimensions for remote-mounted primary reactor starters are shown in Figure 36, p. PFCCs, if required, are housed in a 36-inch wide auxiliary cabinet (not shown). Always consult the submittal drawings for as-built dimensions. -
Page 48: Medium Voltage-Autotransformer (10-13.8 Kv)
Bolted load-side connections for remote starters • Standard motor protection Dimensions Typical dimensions for remote-mounted autotransformer starters are shown in Figure 37, p. PFCCs, if required, are housed in a 36-inch wide auxiliary cabinet (not shown). Always consult the submittal drawings for as-built dimensions. -
Page 49: Electrical System-Ratings
Electrical System—Ratings “Normal” and “overload” conditions … “fault current” … “interrupt” versus “short-circuit” ratings” … “current-limiting. ” Knowing what these terms mean and applying them correctly are fundamental to designing safe, reliable electrical distribution systems.This is especially true in light of more stringent code enforcement and the current design trend to deliver energy savings by selecting low-impedance transformers: How does this influence safety? Lower transformer impedances result in higher short-circuit currents. - Page 50 Electrical System—Ratings 1,500 kVA x 1000/k 480 V x 1.73 x 0.0575 = 31,400 amps Short-circuit current is often two orders of magnitude greater than normal operating current. Unless a circuit breaker or fuse successfully interrupts the fault, this enormous amperage rapidly heats components to very high temperatures that destroy insulation, melt metal, start fires …...
- Page 51 Electrical System—Ratings Overcurrent protective devices (such as fuses and circuit breakers) should be selected to ensure that the short-circuit withstand rating of the system components will not be exceeded should a short circuit or high-level ground fault occur. System components include wire, bus structures, switching, protection and disconnect devices, distribution equipment, etc., all of which have limited short-circuit current ratings and would be damaged or destroyed if these short-circuit current ratings are exceeded.
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Page 52: Electrical System-Design Guidelines
Disconnect Means Low-voltage disconnect Low-voltage starters fromTrane do not have a disconnect means as standard.The standard line power connection is a terminal block (i.e., main lug only) connection. An optional non-fused disconnect switch, in a molded case as shown in Figure 40, can be installed.These non-fused... -
Page 53: Short-Circuit Interruption
All medium- voltage starters have a mechanical interlock to prevent opening the isolation switch while the main contactor is closed and the compressor is running. -
Page 54: Power Circuit Requirements
If you need more detail on the fuses for a particular starter contact CenTraVac Field Sales Support. It turns out that the starter short-circuit current rating is not an issue with medium-voltage starters. ® BecauseTrane medium-voltage starters meet UL 347, current-limiting power fuses are required and provided as standard, and the starter short-circuit current rating no longer applies. - Page 55 Electrical System—Design Guidelines • Additional (non-chiller) loads on the power circuit When evaluating a power system for a chiller-compressor motor with a specified starter type, calculations must be done in order to size or “correct” the power circuit properly in order to successfully start the motor and keep the motor-starter combination online during operation.
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Page 56: Electrical System-Power Wire Sizing
Wiring to motors used with variable frequency drive, across-the-line, autotransformer, or primary reactor starters must be in multiples of three. Wire for these starters is sized following the procedure used for sizing supply wire from the distribution system to the starter. - Page 57 Electrical System–Power Wire Sizing other electrical loads. Branch circuit wires supplying the unit must have an ampacity greater than the MCA. Table 11, p. 58 through Table 16, p. 60 are based on the 2011 NEC conductor ampacities tables for copper wire, run in conduit, in air, for several common wire types and configurations.
- Page 58 Table 11. MCA look-up table for 75°C copper conductors rated for 0–2,000 Volts Note: Use this table to select supply leads for all starters, and motor leads for remote-mounted across-the- line, primary reactor, autotransformer, and Adaptive Frequency Drives. Value in table must be larger than the MCA to use the wire combination.
- Page 59 2375 2850 Note: Use this table to select supply leads for all starters and motor leads for remote-mounted across-the-line, primary reactor, autotransformer, and Adaptive Frequency Drives. Value in table must be larger than the MCA to use the wire combination.
- Page 60 Electrical System–Power Wire Sizing Table 15. MCA look-up table for 90°C copper conductors rated for 2,001–5,000 Volts 1 Conduit 2 Conduits 3 Conduits Wire Size 3 Wires 3 Wires ea. 3 Wires ea. 0000 1155 1425 1200 1800 Note: Use this table to select line-side wiring to the starter and load-side wiring between the starter and the motor. Value in table must be larger than the MCA to use the wire combination.
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Page 61: Starter Options
“bussed” together.This option has a single line power feed for the starter “line-up. ” Additional starters can be added to the lineup as long as each starter has the top-mounted main bus section. Each starter has its own load wires that will run out to the chillers. - Page 62 Starter Options Figure 43. Top-entry, multiple, across-the-line starter arrangement (2.3–6.6 kV) incoming line power 12" 18" pull box main bus X- Line starter X- Line starter 80" 30" 72" Bottom-entry line power Figure 44, p. 63 shows the same concept as above; however, it uses what is called an auxiliary section that allows the customer to bring wires in from the bottom to power the main bus.
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Page 63: Industrial-Grade Starters
72" incoming line power Multiple starter lineups for 10–13.8 kV starters Side-by-side starter lineups are available for 10–13.8 kV starters. Contact CenTraVac Field Sales Support for dimensions and availability. Industrial-Grade Starters High-fault starters can be selected independently of the Enhanced Electrical Protection Package. - Page 64 Starter Options Figure 45. High-fault wye-delta starter Enhanced Electrical Protection Package Applications that require the utmost reliability and rugged construction may prompt the selection of the Enhanced Electrical Protection Package. CenTraVac chillers equipped with the Enhanced Electrical Protection Package are constructed to NEMA 4 guidelines and feature completely enclosed wiring in seal-tight conduits and junction boxes.The Enhanced Electrical Protection Package control panel also includes some additional installation features and layout improvements.The purge is also upgraded to NEMA 4 construction.The entire chiller is silicone-...
- Page 65 Starter Options These and other features listed in the following section allow the CenTraVac to meet or exceed the rigorous criteria of the Society of Automotive Engineers “Standard for Electrical Equipment for Automotive Industrial Machinery, 2002 Edition” (SAE HS-1738). HS-1738 provides requirements and recommendations relating to the electrical equipment of machines so as to promote: •...
- Page 66 In addition to the above standard elements, customers who purchase the Enhanced Electrical Protection Package have additional options.These options can be applied to remote-mounted medium-voltage starters, both fromTrane and from other starter manufacturers. CPTR, Control-Power Transformer (Enhanced Electrical Protection Package option).
- Page 67 (SBO). Most of the accommodations that would need to be met by the customer who wishes to use a non-Trane starter are provided with the Enhanced Electrical Protection Package and the SMP option. Note: Trane-supplied starters already include these items.
- Page 68 It is also important to include the cost of conversion when determining the total cost of a non-Trane starter; therefore, the owner should be provided with the appropriate SBO specification before the decision is made to reuse or purchase a non-Trane starter.
- Page 69 Chillers used with non-Trane starters must ship with a special control panel to accommodate the non-Trane starter. It is the responsibility of theTrane sales representative to select the “Starter by Others (SBO)”...
- Page 70 Engineering Toolbox. Trane has a program called EngineeringToolbox, available online or throughTrane Desktop Manager, that can be used to calculate the kilovolt-amperes reactive (kVAR) of correction needed.Toolbox can calculate kVAR using information from the motor data sheets without adjustments at 60 and 50 Hz.
- Page 71 Starter Options Figure 49. PFCCs installed downstream of starter contactor, upstream of overloads Motor Starter Power Overload Contactor Circuit Protectors Motor Fusible Safety Switch Suitable Breaker Fuses 3-Phase Enclosed Capacitor Capacitor Unit If the capacitor connection points are downstream of the overload devices, route the PFCC leads through the overloads as shown in Figure 50, p.
- Page 72 While this configuration can be used with any type of starter, it is mandatory for all solid-state starters. Notice that the PFCCs are connected to the line side of the main contactor (or other switching device) via a separately controlled contactor.This separate contactor is governed by a pilot relay (PR) at/in the motor-starter...
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Page 73: Glossary
Aluminum conductors copper. It is also possible that the block itself may not be Trane requires that power wiring to the motor use copper suitable for use with aluminum wire as determined by the conductors. Aluminum conductors are not suitable for the block manufacturer. - Page 74 Glossary Amps, primary rated-load amps (RLA) voltage starters with terminal blocks require a special configuration which is available as a standard option in the Commonly referred to as the selection RLA or the unit order system. On medium voltage, the standard UL RLA.
- Page 75 Glossary Current transformer distribution faults—Trane refers to this type of fault as a momentary power loss (MPL). A device that produces a reduced current signal that is proportional to the primary current. A current transformer may resemble a square or round doughnut. Each motor...
- Page 76 The current drawn by a motor during acceleration. Inrush have been exceeded. The contacts of the ground fault current for various types of starters (in percent of LRA) is relay energize a shunt trip device to open the circuit and given in Figure 6, p.
- Page 77 Glossary functions are displayed as standard on the unit controller. voltage starters when customers want Trane to provide a See the comparison tables (Table 2, p. 13 Table 3, load-break switch. The standard isolation switch that 14). comes with medium-voltage starters is non-load break.
- Page 78 Glossary oil pump motor, and purge etc.) MCA is an output of the windblown dust and rain, splashing water, hose-directed TOPSS selection program. Table 11, p. 58 through water, and damage from external ice formation. Table 16, p. 60 show power wire sizing based on the NEMA 4X MCA.
- Page 79 Resistance temperature detector (RTD) Pilot relay A device whose electrical resistance varies with its A term describing the fact that all CenTraVac starters start temperature. RTDs may be used to monitor motor and stop the compressor by means of a relay that winding temperature.
- Page 80 A solid state signal controlled, one-way power switching Switchgear starters should be used with caution. Some device commonly used in solid-state starters and variable- switchgear starters contain a relay that will trip the circuit frequency drives. breaker if auxiliary power is lost. Others do not contain Single phase (single phasing) this auxiliary power monitoring relay.
- Page 81 All medium- voltage power used per time period (i.e., 15 minutes). The value starters used by Trane have vacuum break contactors. displayed is proportional to the electrical energy used in Vacuum break contactors are used typically only on the unit's time period.
- Page 82 HVAC systems, comprehensive building services, and parts. For more information, visit www.Trane.com. Trane has a policy of continuous product and product data improvement and reserves the right to change design and specifications without notice. © 2011 Trane All rights reserved...