26 36 23- Transfer Switches.pdf

26 36 23 – TRANSFER SWITCHES

Herbert, Rowland & Grubic, Inc. 26 36 23-1 005153.0436

SECTION 26 36 23 - TRANSFER SWITCHES

PART 1 - GENERAL

1.1 SUMMARY

A. Provide transfer switches individually wall or floor mounted as shown to transfer from one service source to the other. Units shall receive power from the source to which the switch will transfer.

1.2 SECTION INCLUDES

A. Automatic transfer switches.

1.3 RELATED SECTIONS

A. Division 26.

1.4 REFERENCES

A. NFPA 70 - National Electrical Code.

B. NEMA ICS 1 - General Standards for Industrial Control and Systems.

C. NEMA ICS 2 - Standards for Industrial Control Devices, Controllers, and Assemblies.

D. NEMA ICS 6 - Enclosures for Industrial Controls and Systems.

1.5 SUBMITTALS

A. Submit under provisions of Section 01 33 00 - Submittals.

B. Shop drawings shall be submitted for all materials furnished under this section.

C. The shop drawing shall include, as a minimum, the following equipment specification information. The information shall be highlighted and prove compliance with these specifications.

1. Electrical Ratings - voltage, switch ampere rating, and short circuit ratings.

2. Protective devices and ratings.

3. Elevation drawings, estimated weights, and mounting methods.

4. AC and DC schematic drawings.

5. Performance functions.

6. Sequence of operation.

D. Manufacturer's Instruction - The Contractor shall furnish three copies of a composite instruction book covering this equipment. Each instruction book shall not necessarily be limited to, but shall include as a minimum, the following:

1. Instructions covering overall equipment.

Herbert, Rowland & Grubic, Inc. 26 36 23-2 005153.0436

2. Instructions covering all major and serviceable components.

3. Instructions covering all accessories.

4. Recommended spare parts with current prices, applicable to foregoing paragraphs 1, 2, and 3.

5. Complete renewal parts information.

6. Indicate application conditions and limitations of use stipulated by product testing agency specified under Article 1.08. Include instructions for storage, handling, protection, examination, preparation, installation, and starting of product.

1.6 OPERATION AND MAINTENANCE DATA

A. Contractor shall submit operation and maintenance data in both hard copy and electronic formats. Submit under provisions of Section 01 78 23 – Operations and Maintenance Data. Contractor shall provide manufacturer/supplier with a copy of Section 01 78 23 – Operations and Maintenance Data.

B. Operation Data - Include instructions for operating equipment. Include instructions for operating equipment under emergency conditions when the "normal" electric service is disconnected.

C. Maintenance Data - Include routine preventative maintenance and lubrication schedule.

List special tools, maintenance materials, and replacement parts.

1.7 QUALIFICATIONS

A. Manufacturer - Company specializing in manufacturing the products specified in this section with minimum 10 years' documented experience, and with service facilities within 100 miles of project.

B. Supplier - Authorized distributor of specified manufacturer with minimum 10 years' documented experience.

1.8 REGULATORY REQUIREMENTS

A. Conform to requirements of NFPA 70.

B. Furnish products listed and classified by UL or testing firm acceptable to authority having jurisdiction as suitable for purpose specified and indicated.

C. American National Standards Institute (ANSI).

D. American Society for Testing and Materials (ASTM).

E. National Electrical Manufacturer's Association (NEMA), latest version:

1. ICS 1 - General Standards for Industrial Control and Systems

2. ICS 2 - Standards for Industrial Control Devices, Controllers and Assemblies

3. ICS 4 - Terminal Blocks for Industrial Control Equipment and Systems

Herbert, Rowland & Grubic, Inc. 26 36 23-3 005153.0436

4. ICS 6 - Enclosures for Industrial Controls and Systems

1.9 DELIVERY, STORAGE, AND HANDLING

A. Deliver and store in a clean, dry space. Maintain factory wrapping or provide an additional heavy canvas or heavy plastic cover to protect units from dirt, water, construction debris, and traffic.

B. Handle in accordance with manufacturer's written instructions. Lift only with lugs provided for the purpose. Handle carefully to avoid damage to internal components, enclosure and finish.

1.10 FIELD MEASUREMENTS

A. Transfer switches are wall or pad mounted as shown. Verify switch will fit into the location indicated on the Contract Drawings.

1.11 MAINTENANCE SERVICE

A. Furnish service and maintenance of transfer switch for one year from Date of Substantial Completion.

1.12 MAINTENANCE MATERIALS

A. Provide maintenance materials under provisions of Section 01 78 23 – Operations and Maintenance Data.

1.13 WARRANTY

A. The transfer switch and all appurtenances shall be warranted in accordance with Section 26 05 00 – Electrical-General.

B. In addition to the Contractor's warranty period, the transfer switch shall be warranted by the manufacturer for two years.

PART 2 - PRODUCTS

2.1 MANUFACTURERS

A. ASCO.

B. Cummins.

C. Kohler.

D. Or equal.

Herbert, Rowland & Grubic, Inc. 26 36 23-4 005153.0436

2.2 GENERAL

A. Transfer switches shall be fully rated to protect all types of loads, inductive and resistive, from loss of continuity of power, without derating in the enclosure.

B. It shall not be possible for load circuits to be connected to normal and alternate sources simultaneously. Provide position indicator visible from the front to show the source to which the switch is connected.

C. Double throw, mechanically and electrically interlocked. Breaker-type transfer switches are not acceptable.

D. Operated by momentary energization of bi-directional linear induction motors or single solenoid-type operator with mechanical latching in both normal and emergency positions.

E. Vertical pole arrangement.

F. Switched Neutral.

G. Main Contacts

1. Replaceable, long life, high pressure, silver or silver alloy contacts resistant to burning and pitting.

2. Provide separately removable arcing contacts to protect the main contacts.

3. Contacts shall be sized for maximum amperage rating of the utility supply service as required.

H. Arc Interruption

1. Provide magnetic blowout coils and arc barriers on each pole.

2. Provide covers to prevent interphase flashover. Covers shall be transparent for visual inspection.

I. Connection Lugs - For switches larger than 400 amperes, provide compression type long-barrel, one-hole cable lugs for each power cable, phase and neutral or manufacturer's standard. UL listed solder less screw-type terminal lugs shall also be acceptable, providing they will accommodate the quantity, size and conductor type cable as shown on the Contract Documents or required for the equipment. All terminals front connected and space shall be provided for all lugs as required. Smaller switches shall utilize mechanical lugs.

2.3 AUTOMATIC TRANSFER SWITCH

A. Description - NEMA ICS 2, automatic transfer switch.

B. Configuration - Electrically operated, mechanically held transfer switch.

C. Enclosure Type - NEMA 12.

Herbert, Rowland & Grubic, Inc. 26 36 23-5 005153.0436

2.4 RATINGS

A. Voltage – 208/120 volts, three phase, four wire, 60 Hertz.

B. Poles - three-pole with switched neutral.

C. Continuous Rating – 400 amperes.

D. Interrupting Capacity - 100 percent of continuous rating.

E. Withstand Current Rating - 65,000 rms symmetrical amperes, when used with molded case circuit breaker.

2.5 PRODUCT OPTIONS AND FEATURES

A. Solid-state under voltage sensors to simultaneously monitor all phases of the normal power source and alternate utility source and arrange system for automatic transfer upon failure of or a drop below the adjustable percentage of the normal source voltage.

Field adjustable from 85 to 100 percent of normal source voltage.

B. Retransfer of loads from alternate utility source to normal utility source shall be manually initiated.

C. Operating voltage for transfer shall be obtained from the source to which the load is to be transferred.

D. Provide 0 to 60-second adjustable timer for a "programmed transition," causing the switch to pause in the neutral position during transfer and retransfer for the set period.

E. Provide voltage supervisory relays on each phase, such that transfer is affected should normal three-phase supply fall below 70 percent on normal voltage.

F. Provide four (minimum) auxiliary contacts on shaft (field convertible). No common wires for contacts. Bring wires to terminal block, suitably labeled.

G. Provide indicating lights (door mounted) for the following:

1. Normal switch position.

2. Normal source available.

3. Emergency switch position.

H. Provide auxiliary contacts wired to a terminal block, suitably labeled, for connection to Owner's SCADA system (for future implementation) for indication of the following conditions:

1. Normal source switch position.

2. Normal source available.

3. Alternate source switch position.

Herbert, Rowland & Grubic, Inc. 26 36 23-6 005153.0436

I. Provide any other accessories as may be required to achieve operation as described in this specification.

2.6 AUTOMATIC TRANSFER SWITCH CONTROLS

A. The transfer switch shall be equipped with a microprocessor based control system, to provide all the operational functions of the automatic transfer switch. The controller shall have two asynchronous serial ports. The controller shall have a real time clock with Nicad battery back-up.

B. The CPU shall be equipped with self diagnostics which perform periodic checks of the memory I/O and communication circuits, with a watchdog/power fail circuit

C. The controller shall use industry standard open architecture communication protocol for high speed serial communications via multidrop connection to other controllers and to a master terminal with up to 4000 feet of cable, or further with the addition of a communication repeater. The serial communication port shall be RS422/485 compatible.

D. The serial communication port shall allow interface to either the manufacturer's or the Owner's supervisory control.

E. The controller shall have password protection required to limit access to qualified and authorized personnel.

F. The controller shall include a 20-character, LCD display, with a keypad, which allows access to the system.

G. The controller shall include single & three phase over/under voltage, over/under frequency, phase sequence detection and phase differential monitoring on both normal and alternate utility sources.

H. The controller shall be capable of storing the following records in memory for access either locally or remotely:

1. Number of hours transfer switch is in the emergency position (total since record reset).

2. Number of hours emergency power is available (total since record reset).

3. Total transfer in either direction (total since record reset).

4. Date, time, and description of the last four source failures.

I. Provision to select either "no commit" or "commit" to transfer operation in the event of a normal power failure shall be included. In the "no commit position," the load will transfer to the emergency position unless normal power returns before the emergency source has reach 90 percent of its rated values (switch will remain in normal). In the "commit position" the load will transfer to the emergency position after any normal power failure. Keypad initiated.

Herbert, Rowland & Grubic, Inc. 26 36 23-7 005153.0436

J. A digital LCD voltage readout, with 1 percent accuracy shall display all separate phase to phase voltages simultaneously, for both the normal and alternate utility source.

K. A digital LCD frequency readout with 1 percent accuracy shall display frequency for both normal and alternate utility sources.

L. An LCD readout shall display normal source and alternate utility source availability.

2.7 CONTROLLER

A. The controller shall also be capable of monitoring, logging and trending power data and shall include the following:

1. The controller shall be accurate to 1 percent measured. Voltage and current for all phases shall be sampled simultaneously to assure high accuracy in conditions of low power factor or large waveform distortions (harmonics).

2. The controller shall be capable of operating at nominal frequencies of 45 to 66 Hertz.

3. The controller shall accept inputs from industry standard current transformers (5A secondary). Direct phase voltage connections, 600 VAC and under, shall be possible without the use of PTs.

4. The controller shall be capable of being applied in single or 3-phase, three- and four-wire circuits.

5. All setup parameters required by the controller for power monitoring shall be stored in non-volatile memory and retained in the event of a control power interruption.

6. The following metered readings shall be communicated by the Controller, via local display and serial communication:

a. Current, per phase RMS.

b. Current unbalance percent.

c. Voltage, phase-to-phase and phase-to-neutral.

d. Voltage unbalance percent.

e. Real power (KW), per phase and three-phase total.

f. Apparent power (KVA), per phase and three-phase total.

g. Reactive power (KVAR), per phase and three-phase total.

h. Power factor, three-phase total and per phase.

i. Frequency.

j. Accumulated Energy (KWH, KVAH, and KVARH).

7. Displaying each of the metered quantities shall be accomplished through the use of menu scroll buttons.

8. Setup for systems requirements shall be allowed through the local access display. Setup provisions shall include:

a. CT rating.

b. System type (4-wire).

9. Reset of the following electrical parameters shall also be allowed from the local access display:

a. Real Energy (KWH).

b. Apparent Energy (KVAH).

Herbert, Rowland & Grubic, Inc. 26 36 23-8 005153.0436

c. Reactive Energy (KVARH).

10. All reset and setup functions shall have a menu for protection against unauthorized/accidental changes.

11. The controller shall be capable of storing records in memory for access either locally or remotely for up to 100 events. The reports shall include date, time and a description of the event and shall be maintained in a non-volatile memory.

2.8 ACCESSORIES

A. The following accessories shall be available by simple activation, via the key pad, if required:

1. Include two time delay contacts that open simultaneously just (milliseconds) prior to transfer in either direction. These contacts close after a time delay upon transfer. Programmable 0-9999 seconds after transfer.

2. A load shed function shall be included to disconnect the load from the alternate utility source when an overload condition occurs.

2.9 MOUNTING

A. Automatic transfer switch is to be wall or pad mounted as required.

PART 3 - EXECUTION

3.1 GENERAL

A. Standards and Tests - Equipment covered by these specifications shall be designed, manufactured, assembled, and tested in accordance with the latest revisions of all applicable published ANSI, NEMA, and IEEE standards, and the requirements of the NEC.

B. The Contractor shall submit shop and field test reports and conduct field tests.

C. Owner Acceptance - Final acceptance by the Owner or his duly authorized representative of this equipment shall be contingent upon the equipment satisfactorily meeting these specifications and tests stipulated herein.

3.2 PREPARATION

A. Provide dimensions and weights to the Contractor for his use in providing housekeeping pads where pad mounting is shown. Coordinate installation sequence with the Contractor.

3.3 INSTALLATION

A. The transfer switch and all necessary appurtenances and/or accessories shall be installed in accordance with the manufacturer's installation instructions, approved shop drawings, Contract Drawings and this section.

Herbert, Rowland & Grubic, Inc. 26 36 23-9 005153.0436

B. The Contractor shall field verify existing conditions and shall notify the Owner's Representative of any conditions that need to be corrected prior to commencing the work of this Section. Commencement of work by the Contractor is acceptance of existing conditions.

C. A manufacturer's representative shall supervise, check or assist in the installation of the transfer switch.

D. Provide engraved plastic nameplates under the provisions of Section 26 05 53 – Electrical System Identification.

3.4 FIELD TESTING

A. Field tests shall be conducted on the transfer switch to ensure that the equipment is assembled and installed in accordance with the manufacturer's installation instructions, approved shop drawings, Contract Drawings, and this section. The primary goal of field testing is to ensure the proper installation, setup and operation of equipment or systems. Field testing includes all testing, measuring and adjusting of equipment or systems by the Contractor and/or manufacturer's representative prior to performance testing.

B. Field tests shall be conducted in accordance with the manufacturer's instructions and requirements.

C. Deficiencies identified during field tests shall be corrected.

D. All labor, equipment, water, special tools or apparatus and supplies required for field tests shall be supplied by the Contractor.

E. Field tests shall include, but are not limited to the following, where applicable:

1. Checking the voltage to a piece of equipment or system.

2. Checking the rotation of a motor.

3. Checking the clearance between mounting and mating surfaces.

4. Testing the operation of a manually operated or motorized piece of equipment to ensure smooth operation of mechanisms.

5. Checking the flow rate through a piece of equipment, system or structure.

6. Testing the operation of equipment controls.

7. Any testing of the operation of a piece of equipment or system prior to performance testing.

3.5 PERFORMANCE TESTING AND REPORTING

A. Performance tests shall be conducted on the transfer switch. Performance testing consists of operating the transfer switch in both directions a minimum of ten (10) operations, under actual working or design conditions, of all facility equipment and systems. Installation and all other field testing and adjustments to equipment and systems shall be completed and checked by a manufacturer's representative prior to

Herbert, Rowland & Grubic, Inc. 26 36 23-10 005153.0436 performance testing. A manufacturer's representative shall be present during performance testing. A startup report outlining the results of performance testing shall be prepared by the manufacturer's representative and submitted to the Engineer.

B. Performance tests shall be conducted in accordance with the manufacturer's instructions and requirements.

C. Performance tests shall also be performed in accordance with NETA-Acceptance Testing Specification, Article 7.22.3, latest edition.

D. Deficiencies identified during performance tests shall be corrected and the performance test shall be resumed.

E. All labor, equipment, special tools or apparatus and supplies required for performance tests shall be supplied by the Contractor.

3.6 SERVICES OF MANUFACTURER'S REPRESENTATIVE

A. The Contractor shall arrange for the equipment manufacturer to furnish the services of an authorized and qualified factory representative in accordance with Section 26 05 00 - Electrical General. The manufacturer's representative shall be available to perform the services listed for the durations noted in Sections 01 10 00 - Summary of Work and 01 91 00. Testing shall be conducted by representatives of the manufacturer during the Owner's normal working hours. The Engineer and Owner shall be notified one week in advance in writing and shall witness the tests. Tests to be conducted on-site shall include, but not be limited to, transfer and re-transfer underload.

B. The manufacturer's representative shall prepare a written start-up report per Section 01 33 00 - Submittals, at the conclusion of performance testing. The start-up report shall include an installation certification and shall be submitted directly to the Engineer.

3.7 APPROVALS

A. As a condition of approval, the manufacturer of the automatic transfer switches shall verify that their switches are listed by Underwriters Laboratories, Inc., Standard UL-1008 with three-cycle short circuit closing and withstand.

B. During the three-cycle closing and withstand tests, there shall be no contact welding or damage. The three-cycle tests shall be performed without the use of current limiting fuses. The test shall verify that contacts separation has not occurred, and there is contact continuity across all phases. Test procedures shall be in accordance with UL- 1008, and testing shall be certified by Underwriters' Laboratories, Inc.

C. When conducting temperature rise tests to UL-1008, the manufacturer shall include post-endurance temperature rise tests to verify the ability of the transfer switch to carry full rated current after completing the overload and endurance tests.

D. The microprocessor controller shall meet the following requirements:

Herbert, Rowland & Grubic, Inc. 26 36 23-11 005153.0436

1. Storage Conditions - 25 degrees C to 85 degrees C.

2. Operation Conditions - 20 degrees C to 70 degrees C ambient.

3. Humidity 0 to 99 percent relative humidity, noncondensing.

4. Capable of withstanding infinite power interruptions.

5. Surge withstand per ANSI/IEEE C-37.90A-1978

3.8 DEMONSTRATION

A. Provide systems demonstration under provisions of Section 01 91 00 Commissioning.

Demonstrate operation of transfer switch in normal and alternate utility source modes.

END OF SECTION