July 22, 1994

Contract #TW0592

**SPECIAL SPECIFICATION**

**SECTION 16495**

**[TRANSFER SWITCHES]{.underline}**

**[PART 1 - GENERAL]{.underline} [Page]{.underline}**

1.01 Related Documents 2

1.02 Summary 2

1.03 Remote Annunciation System Description 3

1.04 Remote Annunciation and Control System Description 3

1.05 Submittals 3

1.06 Quality Assurance 4

**[PART 2 - PRODUCTS]{.underline}**

2.01 Manufacturers 6

2.02 Transfer Switch Products, General 6

2.03 Automatic Transfer Switches 8

2.04 Automatic Transfer Switch Features 8

2.05 Bypass/Isolation Switch 10

2.06 Remote Annunciator Panel 10

2.07 Remote Annunciator and Control Panel 11

2.08 Finishes 11

2.09 Source Quality Control 11

**[PART 3 - EXECUTION]{.underline}**

3.01 Installation 12

3.02 Wiring to Remote Components 12

3.03 Connections 12

3.04 Grounding 12

3.05 Field Quality Control 12

3.06 Demonstration 14

**SPECIAL SPECIFICATION**

**SECTION 16495**

**[TRANSFER SWITCHES]{.underline}**

**[PART 1 - GENERAL]{.underline}**

**1.01 [RELATED DOCUMENTS]{.underline}**

> A. Drawings and general provisions of the Contract, including General
> and Supplementary Conditions and Division 1 Specification Sections,
> apply to this Section.

**1.02 [SUMMARY]{.underline}**

> A. This Section includes transfer switches rated 600 V and less. It
> includes the following items:
>
> 1\. Automatic transfer switch (ATS).
>
> 2\. Bypass/isolation switch (BP/IS).
>
> 3\. Nonautomatic transfer switch (NATS).
>
> 4\. Remote annunciation system.
>
> 5\. Remote annunciation and control system.
>
> B. Related Sections: The following Sections contain requirements that
> relate to this Section:
>
> 1\. Transfer switches integral with uninterruptible power supply
> systems are specified in Division 16 Section \"Uninterruptible Power
> Supply Systems.\"
>
> 2\. Transfer switches integral with battery systems are specified in
> Division 16 Section \"Central Battery Inverter System.\"
>
> 3\. Conductors for hard-wired connections between transfer switches
> and remote equipment are specified in Division 16 Section \"Wires and
> Cables.\"
>
> 4\. Data circuits between transfer switches and remote panels are
> specified in Division 16 Section \"Control/Signal Transmission
> Media.\"

**1.03 [REMOTE ANNUNCIATION SYSTEM DESCRIPTION]{.underline}**

> A. Functional Description: A remote annunciator panel annunciates
> conditions at indicated transfer switches including:
>
> 1\. Sources available (as defined by actual pick-up and drop-out
> settings of transfer switch controls).
>
> 2\. Switch position.
>
> 3\. Switch in test mode.
>
> 4\. Failure of digital communications link.

**1.04 [REMOTE ANNUNCIATION AND CONTROL SYSTEM
DESCRIPTION]{.underline}**

> A. Functional Description: A remote annunciation and control panel
> provides the functions listed below at indicated transfer switches:
>
> 1\. Sources-available indication (as defined by actual pick-up and
> drop-out settings of transfer switch controls).
>
> 2\. Switch position indication.
>
> 3\. Switch in test mode indication.
>
> 4\. Failure of digital communications link indication.
>
> 5\. Key switch or user code access to control functions of panel.
>
> 6\. Control of switch test initiation.
>
> 7\. Control of switch operation in either direction.
>
> 8\. Control of bypass of time delay for transfer to normal source.
>
> B. Malfunction of the annunciator unit or communication link does not
> affect functions of the ATS. In the event of a failure of the
> communication link the ATS automatically reverts to stand-alone,
> self-contained operation. No ATS sensing, controlling, or operating
> function depends on the remote panel for proper operation.

**1.05 [SUBMITTALS]{.underline}**

> A. General: Submit the following according to Conditions of Contract
> and Division 1 Specification Sections.
>
> B. Shop drawings or published product data for each transfer switch,
> including dimensioned plans, sections, and elevations showing minimum
> clearances; conductor entry provisions; gutter space; installed
> features and devices; and materials lists.
>
> C. Wiring diagrams, elementary or schematic, differentiating between
> manufacturer-installed and field-installed wiring.
>
> D. Single-line diagrams of transfer switch units showing connections
> between automatic transfer switch, bypass/isolation switch, power
> source, and load, plus interlocking provisions.
>
> E. Operation and maintenance data for each type of product, for
> inclusion in Operating and Maintenance Manual specified in Division 1.
> Include all features and operating sequences, both automatic and
> manual. List all factory settings of relays and provide relay setting
> and calibration instructions.
>
> F. Manufacturer\'s certificate of compliance to the referenced
> standards and tested short-circuit closing and withstand ratings
> applicable to the protective devices and current ratings used in this
> Project, as indicated and as specified in paragraph \"Tested Fault
> Current Ratings.\"

**1.06 [QUALITY ASSURANCE]{.underline}**

> A. Manufacturer\'s Qualifications: Firms are experienced in
> manufacturing equipment of the types and capacities indicated and have
> a record of successful in-service performance.
>
> B. Emergency Service: Manufacturer maintains a service center capable
> of providing emergency maintenance and repairs at the Project site
> with an 8-hour maximum response time.
>
> C. Comply with NFPA 70, \"National Electrical Code,\" for components
> and installation.
>
> D. Comply with NFPA 99, \"Standard for Essential Electrical Systems
> for Health Care Facilities,\" and NFPA 110, \"Standard for Emergency
> and Standby Power Systems.\"
>
> E. Comply with NEMA ICS 1, \"General Standards for Industrial
> Control,\" ICS 2, \"Industrial Control Devices, Controllers and
> Assemblies,\" and ICS 6, \"Enclosures for Industrial Controls and
> Systems.\"
>
> F. UL Listing and Labeling: Items furnished under this Section are
> listed and labeled by UL for emergency service under UL Standard 1008.
>
> G. Nationally Recognized Testing Laboratory Listing (NRTL) and
> Labeling: Items furnished under this Section are listed and labeled by
> a NRTL for emergency service under UL Standard 1008.
>
> 1\. Terms \"Listed\" and \"Labeled\": As defined in the \"National
> Electrical Code,\" Article 100.
>
> 2\. Listing and Labeling Agency Qualifications: A \"Nationally
> Recognized Testing Laboratory\" (NRTL) as defined in OSHA Regulation
> 1910.7.
>
> H. UL Compliance: Comply with UL Standard 1008, \"Automatic Transfer
> Switches,\" except where requirements of these Specifications are
> stricter.
>
> I. Single-Source Responsibility: Obtain ATSs, BP/ISs, remote
> annunciators, and remote annunciator and control panels from a single
> manufacturer that assumes responsibility for all system components
> furnished.

**[PART 2 - PRODUCTS]{.underline}**

**2.01 [MANUFACTURERS]{.underline}**

> A. Available Manufacturers: Subject to compliance with requirements,
> manufacturers offering products that may be incorporated in the Work
> include, but are not limited to, the following:
>
> B. Manufacturers: Subject to compliance with requirements, provide
> products by the following:
>
> 1\. Automatic Switch Co.
>
> 2\. Caterpillar, Inc.
>
> 3\. Kohler Co.
>
> 4\. Onan Corp.
>
> 5\. Russelectric, Inc.
>
> 6\. Zenith Controls, Inc.

**2.02 [TRANSFER SWITCH PRODUCTS, GENERAL]{.underline}**

> A. Number of Poles and Current and Voltage Ratings: As indicated.
>
> 1\. Units smaller than 600 amperes do not have different current
> ratings for different classes or mixtures of loads, including 100
> percent tungsten filament lamp or 100 percent inductive load.
>
> 2\. Units 600 amperes and larger have current ratings that apply to
> mixtures of loads including 30-percent-maximum tungsten filament lamp
> load.
>
> B. Tested Fault-Current Ratings: Closing and withstand ratings exceed
> the indicated available rms symmetrical fault current at the equipment
> terminals based on testing according to UL Standard 1008, conducted at
> full-rated system voltage and 20 percent power factor. Rate each
> product for withstand duration time as follows when tested for rated
> short-circuit current correlated with the actual type of circuit
> protective device indicated for transfer switches for this Project:
>
> 1\. Molded-Case Circuit Breakers, 150 Amperes or Smaller: 1.5 closing
> and withstand duration cycles.
>
> 2\. Molded-Case Circuit Breakers, Larger than 150 Amperes: 3 closing
> and withstand duration cycles.
>
> 3\. Power Circuit Breakers: 10 closing and withstand duration cycles.
>
> 4\. Current-Limiting Fuses: 0.5 (nominal) closing and withstand
> duration cycles.
>
> C. Annunciation and Control Interface Components: Devices at transfer
> switches for communicating with remote annunciators or
> annunciator/control panels have communications capability matched with
> the remote device.
>
> D. Solid-State Controls: Repetitive accuracy of all settings is plus
> or minus 2 percent or better over an operating temperature range of
> minus 20 deg C to 70 deg C.
>
> E. Resistance to Damage by Voltage Transients: Components meet or
> exceed voltage surge withstand capability requirements when tested
> according to ANSI C37.90.1, IEEE Guide for Surge Withstand Capability
> (SWC) Tests. Components meet or exceed voltage impulse withstand test
> of NEMA ICS 1.
>
> F. Four-Pole Switches: Provide full-capacity neutral switching.
>
> G. Enclosures: General-purpose NEMA 1, conforming to UL Standard 508,
> \"Electric Industrial Control Equipment,\" except as otherwise
> indicated.
>
> H. Factory Wiring: Train and bundle factory wiring and identify
> consistently with shop drawings, either by color code or by numbered
> or lettered wire and cable tape markers at terminations.
>
> 1\. Designated terminals accommodate field wiring.
>
> 2\. Power Terminals Arrangement and Field Wiring Space: Suitable for
> top, side, or bottom entrance of feeder conductors as indicated.
>
> 3\. Terminals: Pressure-type, suitable for copper or aluminum
> conductors of sizes indicated.
>
> 4\. Control Wiring: Equipped with lugs suitable for connection to
> terminal strips.
>
> I. Electrical Operation: Where indicated, accomplish by a nonfused,
> momentarily energized solenoid or electric motor-operated mechanism,
> mechanically and electrically interlocked in both directions. Switches
> using components of molded-case circuit breakers or contactors not
> designed for continuous-duty, repetitive switching between active
> power sources are not acceptable.
>
> J. Switch Action: Mechanically held in both directions for
> double-throw switches.
>
> K. Switch Contacts: Use silver composition for switching load current.
> Units rated 225 amperes and more have separate arcing contacts.
>
> L. Overcurrent devices are not part of switch products.

**2.03 [AUTOMATIC TRANSFER SWITCHES (ATSs)]{.underline}**

> A. Comply with Level 1 equipment according to NFPA 110, \"Standard for
> Emergency and Standby Power Systems.\"
>
> B. Switching Arrangement: Double-throw type, incapable of pauses or
> intermediate position stops during normal functioning except as
> indicated.
>
> C. Manual Switch Operation: Manually operated under load with the door
> closed with either or both sources energized. Transfer time is same as
> for electrical operation. Control circuit automatically disconnects
> from electrical operator during manual operation.
>
> D. Signal-Before-Transfer Contacts: A set of normally open/normally
> closed dry contacts operates in advance of retransfer to normal
> source. Interval is adjustable from 1 to 30 seconds.
>
> E. Digital Communications Interface: Full-duplex RS 422 type, matched
> to capability of remote annunciator or annunciator and control panel.

**2.04 [AUTOMATIC TRANSFER SWITCH FEATURES]{.underline}**

> A. Voltage sensing for each phase of normal source. Pick-up voltage is
> adjustable from 85 percent to 100 percent nominal, and drop-out
> voltage is adjustable from 75 percent to 98 percent pick-up value.
> Factory set for pick-up at 90 percent and drop-out at 85 percent.
>
> B. Time-delay override of normal source voltage-sensing delays
> transfer and engine start signals. Adjustable 0 to 6 seconds, and
> factory set at 1 second.
>
> C. Voltage/Frequency Lockout Relay: Prevent premature transfer.
> Voltage pick-up is adjustable from 85 percent to 100 percent nominal.
> Factory set to pick-up at 90 percent. Pick-up frequency is adjustable
> from 90 percent to 100 percent nominal. Factory set to pick-up at 95
> percent.
>
> D. Retransfer Time Delay: Adjustable from 0 to 30 minutes and factory
> set at 10 minutes. Provides automatic defeat of the delay upon loss of
> voltage or sustained undervoltage of the emergency source, provided
> the normal supply has been restored.
>
> E. Test Switch: Simulates normal source failure.
>
> F. Switch-Position Pilot Lights: Indicate source to which the load is
> connected.
>
> G. Source-Available Indicating Lights: Supervise sources via the
> transfer switch normal and emergency source-sensing circuits.
>
> 1\. Normal Power Supervision: Green light with nameplate engraved
> \"Normal Source Available.\"
>
> 2\. Emergency Power Supervision: Red light with nameplate engraved
> \"Emergency Source Available.\"
>
> H. Unassigned Auxiliary Contacts: Two normally open SPDT contacts for
> each switch position.
>
> 1\. Rating: 10 amperes at 240 V a.c.
>
> I. Transfer Override Switch: Overrides automatic retransfer control so
> the ATS will remain connected to the emergency power source regardless
> of the condition of the normal source. A pilot light indicates the
> override status.
>
> J. Engine Starting Contacts: One isolated normally closed and 1
> isolated normally open. Contacts are gold flashed or gold plated and
> rated 10 amperes at 32 V d.c. minimum.
>
> K. Engine Shut-Down Contacts: Instantaneous, to initiate shut-down
> sequence at remote engine-generator controls after retransfer of the
> load to normal or preferred source.
>
> L. Engine Shut-Down Contacts: Time delay adjustable from 0 to 5
> minutes; factory set at 5 minutes.
>
> M. Engine-Generator Exerciser: Solid-state programmable time switch
> starts engine-generator set and transfers load to it from normal
> source for a preset time, then retransfers and shuts down engine after
> a preset cool-down period. Initiate exercise cycle at preset intervals
> adjustable from 7 to 30 days. Running periods are adjustable from 10
> to 30 minutes. Factory-set periods are for 7 days and 20 minutes,
> respectively. Exerciser features include:
>
> 1\. Exerciser transfer selector switch, which permits selection
> between exercise with and without load transfer.
>
> 2\. Push button programming controls with digital display of settings.
>
> 3\. Integral battery operation of time switch when normal control
> power is not available.

**2.05 [BYPASS/ISOLATION SWITCH (BP/IS)]{.underline}**

> A. Comply with requirements for Level 1 equipment per NFPA 110,
> Standard for Emergency and Standby Power Systems.
>
> B. Description: Manual type, arranged to select and connect either
> source of power directly to the load, isolating the transfer switch
> from the load and from both power sources. Include the following
> features:
>
> 1\. Means to lock the BP/IS in the position that isolates the transfer
> switch, with an arrangement that permits complete electrical testing
> of the transfer switch while isolated. While isolated, interlocks
> prevent transfer switch operation except for testing or maintenance.
>
> 2\. Draw-Out Arrangement for the Transfer Switch: Provides physical
> separation from live parts for testing and maintenance operations.
>
> 3\. Current, Voltage, Closing, and Short-Circuit Withstand Ratings:
> Equal to or greater than that of the associated ATS, with the same
> phase arrangement and number of poles.
>
> 4\. Contact temperatures of BP/IS do not exceed those of ATS contacts
> when they are carrying rated load.
>
> 5\. Operability: Constructed so that load bypass and transfer switch
> isolation can be performed by 1 person in no more than 2 operations in
> 15 seconds or less.
>
> 6\. Legend: Manufacturer\'s standard legend for control labels and
> instruction signs give detailed operating instructions.
>
> 7\. Maintainability: Fabricate BP/IS to allow convenient removal of
> major components from the front without removal of other parts or main
> power conductors.
>
> C. Interconnect BP/IS and ATS with copper bus bars plated at
> connection points and braced for the indicated available short circuit
> current.

**2.06 [REMOTE ANNUNCIATOR PANEL]{.underline}**

> A. Description: Hard-wired lamp type with audible signal and silencing
> switch. Indicating lights are grouped for each transfer switch
> monitored. Label each group indicating the transfer switch it
> monitors, the location of the switch, and the identity of the load it
> serves.
>
> B. Mounting: Flush, modular, steel cabinet except as indicated.
>
> C. Lamp Test: Push-to-test or \"lamp test\" switch on front panel.

**2.07 [REMOTE ANNUNCIATOR AND CONTROL PANEL]{.underline}**

> A. Description: Solid-state control and indicating panel. Group
> controls and indicating lights for each transfer switch together.
> Label each group indicating the transfer switch it controls, the
> location of that switch, and the load it serves.
>
> B. Digital Communications Capability: Matched to that of transfer
> switches supervised.
>
> C. Mounting: Flush, modular, steel cabinet except as indicated.

**2.08 [FINISHES]{.underline}**

> A. Enclosures: Manufacturer\'s standard enamel over
> corrosion-resistant pretreatment and primer.

**2.09 [SOURCE QUALITY CONTROL]{.underline}**

> A. Factory test components, assembled switches, and associated
> equipment to ensure proper operation. Check transfer time and voltage,
> frequency, and time-delay settings for conformance with specified
> requirements. Perform dielectric strength test conforming to NEMA ICS
> 1.

**[PART 3 - EXECUTION]{.underline}**

**3.01 [INSTALLATION]{.underline}**

> A. Floor Mounting of Transfer Switches: Level and anchor the unit to
> the floor.
>
> B. Annunciator Panel Mounting: Mount flush in wall except as
> indicated.
>
> C. Identify components according to Division 16 Section \"Electrical
> Identification.\"

**3.02 [WIRING TO REMOTE COMPONENTS]{.underline}**

> A. Match the type and number of cables and conductors to the control
> and communications requirements of the transfer switches used.
> Increase raceway sizes at no additional cost to the owner if necessary
> to accommodate required wiring.

**3.03 [CONNECTIONS]{.underline}**

> A. Tighten factory-made connections, including connectors, terminals,
> bus joints, mountings, and grounding. Tighten field-connected
> connectors and terminals, including screws and bolts, according to
> equipment manufacturer\'s published torque tightening values. When
> manufacturer\'s torquing requirements are not indicated, tighten
> connectors and terminals to comply with tightening torques specified
> in UL Standards 486A and 486B.

**3.04 [GROUNDING]{.underline}**

> A. Make equipment grounding connections for transfer switch units as
> indicated and as required by the NEC.

**3.05 [FIELD QUALITY CONTROL]{.underline}**

> A. Manufacturer\'s Field Services: Provide services of a
> factory-authorized service representative to supervise field tests.
>
> B. Preliminary Tests: Perform electrical tests as recommended by the
> manufacturer and as follows:
>
> 1\. Measure phase-to-phase and phase-to-ground insulation resistance
> levels with insulation resistance tester, including external
> annunciator and control circuits. Use test voltages and procedure
> recommended by the manufacturer. Meet manufacturer\'s specified
> minimum resistance.
>
> 2\. Check for electrical continuity of circuits and for short
> circuits.
>
> C. Field Tests: Give 7-day advance notice of the tests and perform
> tests in presence of owner\'s representative.
>
> D. Coordinate tests with tests of generator plant and run them
> concurrently.
>
> E. Tests: As recommended by the manufacturer and as follows:
>
> 1\. Contact Resistance Test: Measure resistance of power contacts for
> ATSs, NATSs, and BP/ISs. Resolve values in excess of 500 micro-ohms
> and differences between adjacent poles exceeding 50 percent.
>
> 2\. Ground Fault Tests: Coordinate with testing specified in Division
> 16 Section \"Overcurrent Protective Devices\" to ensure sensors are
> properly selected and located to optimize ground-fault protection
> where power is being delivered from either source.
>
> a\. Verify grounding points and sensor ratings and locations.
>
> b\. Apply simulated fault current at the sensors and observe reaction
> of circuit interrupting devices.
>
> 3\. Operational Tests: Demonstrate interlock, sequence, and
> operational function for each switch at least 3 times.
>
> a\. Simulate power failures of normal source to ATSs and of emergency
> source with normal source available.
>
> b\. Simulate low phase-to-ground voltage for each phase of normal
> source of ATSs.
>
> c\. Verify time-delay settings and pick-up and drop-out voltages.
>
> F. Test Failures: Correct deficiencies identified by tests and prepare
> for retest. Verify that equipment meets the specified requirements.
>
> G. Reports: Maintain a written record of observations and tests.
> Report defective materials and workmanship and retest corrected items.
> Record adjustable relay settings and measured insulation and contact
> resistances and time delays. Attach a label or tag to each tested
> component indicating satisfactory completion of tests.

**3.06 [DEMONSTRATION]{.underline}**

> A. Training: Furnish the services of a factory-authorized service
> representative to instruct Owner\'s personnel in the operation,
> maintenance, and adjustment of transfer switches and related
> equipment. Provide a minimum of 4 hours of instruction scheduled 7
> days in advance.
>
> END OF SECTION 16495