Low_Voltage_Switchboards_Pre-Purchase_Package_SPECS_DRAWINGS.pdf

Architectural & Engineering Services for Wastewater Treatment Backup Generators

Low Voltage Switchboards Pre-Purchase Package March 2026

Hazen and Sawyer

999 Ponce de Leon Boulevard, Suite 1150

Coral Gables, Florida 33134 • (305) 443-4001

Hazen and Sawyer

EXECUTIVE SUMMARY

Architectural & Engineering Services for Wastewater Treatment Plant Backup Generators

Low Voltage Switchboards Pre-Purchase Package

The City of Homestead (City) is undertaking a critical infrastructure initiative to enhance the resilience and operational reliability of its wastewater treatment facility during electrical service interruptions. Supported by funding from the U.S. Department of Housing and Urban

Development’s Community Development Block Grant Mitigation Program, the project will ensure that the facility can maintain full operational capability during utility outages.

Due to extended equipment lead times, the City has elected to pre-purchase key components of the facility’s backup power system. These components include three (3) diesel engine generators, a generator output switchboard (SWBD-GEN) equipped with permanent connections for a portable generator, and a distribution switchboard (SWBD-DIST) housing an Automatic Transfer

Controller (ATC).

The three (3) generators will operate in parallel under the control of a Master Paralleling

Controller. The generator output switchboard will serve as the common collection point for the generator outputs, combining them into one output connection that powers the distribution switchboard. The generator output switchboard also includes a permanent portable generator connection, as required by the National Electrical Code (NEC), to provide an additional layer of operational continuity during scheduled maintenance or when the permanent generators are unavailable. The ATC at the distribution switchboard will perform all monitoring, control, and transfer operations required to automatically switch between utility and generator power during outages and subsequently return the load to utility power once conditions stabilize.

For procurement efficiency, the City has divided the overall pre-purchase effort has been divided into two packages. This package specifically covers the furnishing of the generator output switchboard (SWBD-GEN) and the distribution switchboard (SWBD-DIST).

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LOW VOLTAGE SWITCHBOARDS PRE-PURCHASE PACKAGE

SECTION 00 01 10

TABLE OF CONTENTS

DIVISION 26 − ELECTRICAL

Section Title

26 05 73 Power System Studies

26 09 16 Electric Controls and Relays

26 24 13 Low Voltage Switchboards

26 43 13 Surge Protective Devices

ATTACHMENTS

Attachment A Low Voltage Switchboards Division of Responsibilities

Attachment B Electrical Drawings

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SECTION 26 05 73

POWER SYSTEM STUDIES

PART 1 – GENERAL

1.01 THE REQUIREMENT

A. The SWITCHBOARD MANUFACTURER shall provide all power system studies for the project as specified herein. The following shall be performed:

1. Short Circuit Studies

2. Load Flow Analyses

3. Protective Device Coordination Studies

4. Equipment Evaluation

5. Arc Flash Risk Assessment

B. The scope of the work for these studies shall include all existing electrical equipment as well as new electrical equipment furnished under this Contract at the project site.

C. The studies shall include all electric utility protective devices, transformers, generators, cables, switchgear, switchboards, motor control centers, individual motor controllers, variable-frequency drives, panelboards, protection relays, and control panels.

D. Prior to receiving final approval of the distribution equipment shop drawings for the equipment proposed under this Contract and/or prior to release of that equipment for manufacture, the Preliminary Report, as specified herein, shall be submitted and approved. SWITCHBOARD MANUFACTURER shall expedite the completion of the

Preliminary Report so that final approval of proposed equipment is not delayed.

E. The studies shall be performed with the aid of SKM Systems Analysis Power Tools for

Windows (PTW) software, Version 11.0 or newer. No other software analysis packages are acceptable.

1.02 CODES AND STANDARDS

A. All work shall be performed in accordance with the following Codes and Standards, as applicable (latest edition, unless otherwise specified):

1. Institute of Electrical and Electronic Engineers (IEEE):

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a. Standard 141, Recommended Practice for Electric Power Distribution for

Industrial Plants

b. Standard 241, Recommended Practice for Electric Power Systems in

Commercial Buildings

c. Standard 242, Recommended Practice for Protection and Coordination of

Industrial and Commercial Power Systems

d. Standard 3002.2, IEEE Recommended Practice for Conducting Load Flow

Studies and Analysis of Industrial and Commercial Power Systems

e. Standard 3002.3, IEEE Recommended Practice for Conducting Short-Circuit

Studies and Analysis of Industrial and Commercial Power Systems

f. Standard 1584-2018, IEEE Guide for Performing Arc-Flash Hazard

Calculations

2. American National Standards Institute (ANSI):

a. Standard C37.90, IEEE Standard for Relays and Relay Systems Associated with Electric Power Apparatus

b. Standard C37.91, Guide for Protective Relay Applications to Power

Transformers

c. Standard C37.95, Guide for Protective Relaying of Utility-Consumer

Interconnections

d. Standard C37.96, Guide for AC Motor Protection

e. Standard C57.12.59, Guide Dry-Type Transformer Through-Fault Current

Duration

f. Standard C.57.13, Standard Requirements for Instrumentation Transformers

g. Standard C57.109, Guide for Liquid-Immersed Transformer Through Fault-

Current Duration

h. Standard Z535.4, Product Safety Signs and Labels

3. National Fire Protection Association (NFPA):

a. NFPA 70, National Electrical Code (NEC)

b. NFPA 70E, Standard for Electrical Safety in the Workplace (2024 Edition)

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1.03 SUBMITTALS

A. The SWITCHBOARD MANUFACTURER shall submit the following reports for review and approval:

1. One (1) printed copy and one (1) electronic copy of the Preliminary Report.

2. One (1) printed copy and one (1) electronic copy of the Pre-final Report.

3. Two (2) printed copies and one (1) electronic copy of the Final Report.

B. The SWITCHBOARD MANUFACTURER shall submit one (1) complete electronic copy of the final power system model and all required database files generated by the software analysis package used. Files shall be placed on portable storage media (USB

3.0 flash storage device) or be uploaded to a cloud-based file sharing service and be submitted with the Final Report. Furnish any necessary documentation requiring the

Owner’s signature to allow model to be transferred to the Owner.

1.04 QUALIFICATIONS

A. The studies shall be performed by a professional electrical engineer actively licensed in the state or commonwealth in which the project is located. The licensed professional electrical engineer shall have a minimum of five (5) years of experience in performing power system studies.

B. The resume of the licensed professional electrical engineer shall be submitted for approval prior to the start of work. An experience table shall also be provided detailing the power system studies of similar scope to this Contract that have been performed by the proposed engineer over the last two (2) years. The table shall, at a minimum, list the facility owner’s name, facility contact person with phone number and email address, and overall scope of work that was provided.

PART 2 – PRODUCTS (NOT USED)

PART 3 – EXECUTION

3.01 DATA COLLECTION

A. The SWITCHBOARD MANUFACTURER shall collect all required utility transformer and service information for use in these studies. The Engineer shall provide the electric utility representative contact information.

B. Approved equipment shop drawings and product information for all equipment furnished under this Contract shall be used for these studies. Including data for equipment that is not yet approved is not acceptable.

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C. One (1) field visit to the project site to collect pertinent data from existing equipment by the personnel performing the studies is permitted. The visit shall span as many days as required to collect all necessary information. This visit shall occur as soon after the

Contract is awarded as possible and shall be coordinated with the Owner. The

SWITCHBOARD MANUFACTURER and personnel performing these studies are responsible for collecting all required data for these studies. If equipment is to be examined while energized parts are exposed, the examining personnel shall wear appropriate PPE in accordance with the requirements of NFPA 70E.

D. Using data from record drawings, “as-built” drawings, or a previous power system study is not acceptable. All data for existing equipment shall be field verified.

3.02 STUDY PARAMETERS

A. The following parameters shall be used for all studies:

1. Transformers 75kVA (nominal) and larger shall be modeled with actual nameplate data including impedance data. Motors 30hp and larger shall be modeled with actual nameplate power factor and efficiency data.

2. Room heating and cooling loads are mutually exclusive. Only the larger of these two load types shall be configured as in-service in the model.

3. Some sets of pumps for a specific application have one redundant unit. For the purposes of these studies, that redundant unit shall be configured as out-of-service in the model. The SWITCHBOARD MANUFACTURER shall coordinate with the

Owner to determine which pumps are considered redundant.

4. The sources that shall be used in these studies are the serving electric utility and the standby generator. These sources are incapable of paralleling with each other, so each one shall be considered independent of the other for the purposes of these studies.

B. Other parameters may apply for specific studies if noted in the respective study requirements herein.

3.03 SHORT CIRCUIT STUDIES

A. The short circuit studies shall be performed in accordance with IEEE Standard 3002.3.

B. The study input data shall include the short circuit contribution obtained from each source. Short circuit close and latch duty values and interrupting duty values shall be calculated on the basis of assumed three-phase bolted short circuits at each bus. Single-line diagrams shall show the results of the analysis by using datablocks constructed as shown in Appendix A. Provide the results of this study in a tabular format as well, included as an appendix to the report.

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C. The short circuit study report shall include an analysis of whether the equipment short circuit and withstand ratings shown in the Contract Documents are suitable.

3.04 PROTECTIVE DEVICE COORDINATION STUDIES

A. A protective device coordination study shall be performed to provide the necessary calculations and logic decisions required to select or to check the selection of power fuse ratings, protective relay characteristics and settings, ratios and characteristics of associated current transformers, and low voltage circuit breaker trip characteristics and settings.

B. The coordination study shall include all equipment from the serving electric utility company source protective devices down to and including all adjustable circuit protective devices. The phase and ground overcurrent protection shall be included as well as settings of all other adjustable protective devices.

C. The time-current characteristics of the proposed protective devices shall be printed on log-log scale coordination plots as specified below.

1. Each plot shall be accompanied by a representative single-line diagram. The coordination plot and single-line diagram shall each occupy one-half of the same printed sheet for ease of cross reference. Each printed sheet shall have a distinct title that identifies the portion of the electrical system it represents.

2. Each coordination plot shall include the following:

a. Sufficient number of separate curves shall be used to clearly indicate the coordination achieved

b. Identification of each curve with its respective component’s name

c. Complete operating bands for fuse and low voltage circuit breaker trip curves

d. Transformer magnetizing inrush and ANSI transformer withstand parameters

e. Cable thermal overcurrent withstand limits

f. Significant symmetrical and asymmetrical fault currents for the portion of the electrical system represented by the plot

3. Each accompanying single-line shall include datablocks as described in Appendix

A.

4. All restrictions of the National Electrical Code shall be adhered to, and proper coordination intervals and separation of characteristic curves shall be maintained.

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D. The selection and settings of all protective devices shall be provided separately in the report in a tabulated form listing circuit identification, IEEE device number, current transformer ratios and connections, manufacturer and type, range of adjustment and recommended settings.

3.05 LOAD FLOW ANALYSIS

A. The load flow analysis shall be performed in accordance with IEEE Standard 3002.2.

B. A load flow analysis shall be performed to determine the steady-state loading profile of the system(s) being studied. From the results of the load flow analysis, the report shall indicate areas of overloaded conductors, busses, or other equipment in the power distribution system. The load flow analysis results shall be presented in a tabular format as well as a single-line diagram format. Single-line diagrams shall show the results of the analysis by using datablocks constructed as shown in Appendix A. All assumptions associated with the analysis shall be documented in the report.

3.06 EQUIPMENT EVALUATION

A. An equipment evaluation shall be performed to determine the adequacy of existing circuit breakers, panelboards, motor control centers, automatic transfer switches, busses, etc. located at the facility by tabulating and comparing the short circuit ratings of these devices with the calculated fault currents that result from the short circuit study.

B. Appropriate multiplying factors based on system X/R ratios and protective device rating standards shall be applied. A table shall be provided in the report showing the calculated fault currents and the corresponding short circuit ratings of the existing equipment along with a pass or fail status for each piece of equipment.

3.07 ARC FLASH RISK ASSESSMENT

A. An arc flash risk assessment shall be performed in accordance with IEEE Std. 1584-

2018, NFPA 70E, and OSHA 29-CFR, Part 1910 Subpart S. The assessment shall use the incident energy analysis method. The arc flash PPE category method shall not be used.

B. The following parameters shall be used for the arc flash risk assessment:

1. Working distance for all equipment: 18 inches

2. Arcing duration limit: 2 seconds, or higher (based on engineering judgement) for equipment locations where additional time may be required to exit the arc flash boundary.

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3. Equipment box dimensions and electrode configuration shall be entered for each piece of equipment (existing and/or new) to be assessed. Using software default dimensions and electrode configuration is not acceptable.

4. For equipment operating at 240VAC or below, report incident energy as “<1.2 cal/cm2” if the bolted fault current is calculated to be less than 2000A.

5. Any protective device settings changes that were recommended as part of these studies shall be included. For devices where settings changes are recommended, the “as-found” settings shall be documented separately in dedicated tables for record purposes.

6. The following operational scenarios shall be used in the assessment, with the worst-case values from each scenario being shown in the study report and on the arc flash labels:

a. Scenario 1: Main circuit breaker is closed, generator circuit breaker is open, and the facility is served by the electric utility source.

b. Scenario 2: Main circuit breaker is open, generator circuit breaker is closed, and the facility is served by the standby generator source.

C. The arc flash risk assessment report shall include but not be limited to the following:

1. A brief overview of what arc flash hazards are and how to avoid them.

2. Definitions of key terms used in the report.

3. Confirmation of all parameters and scenarios used in the report.

4. Documentation of any assumptions made for the report.

5. Serving electric utility information received. Copies of the information received shall be included in an appendix.

6. Any recommendations to reduce the arc flash incident energies via protective device settings changes where incident energies are found to exceed 12 cal/cm2.

Protective device settings change recommendations shall not negatively impact selective coordination.

7. A copy of the PPE information from Table 130.5 G in NFPA 70E.

8. Arc flash labels as specified herein.

9. An NFPA 70E energized electrical work permit for each location where an arc flash label is provided.

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10. An arc flash evaluation summary sheet, based on the worst-case scenario, that contains the following minimum information:

a. Bus name

b. Protective device name

c. Bus line-to-line voltage

d. Bus bolted fault

e. Protective device bolted fault

f. Protective device arcing fault

g. Trip/delay time

h. Breaker opening time

i. Equipment type

j. Gap

k. Electrode configuration

l. Box height, width, and depth

m. Arc flash boundary

n. Working distance

o. Incident energy

p. Notes

D. Arc Flash Labels

1. Arc flash labels shall be provided for each piece of equipment that is likely to require examination, adjustment, servicing, or maintenance while energized.

When opening an enclosure exposes energized parts on both the line and load side of a device, provide a label with the worst case (line versus load) incident energy printed. The following equipment, at a minimum, shall be provided with labels in the quantities specified:

a. Switchgear/Switchboards – quantity of 1 label per section on front, 1 label per section on rear if rear is accessible. Provide second label at main circuit

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breaker sections where it is possible to open covers and separately expose line side and load side energized parts.

b. Motor control centers – quantity of 1 label per section on front, 1 label per section on rear if rear is accessible. Provide second label at main circuit breaker sections where it is possible to open covers and separately expose line side and load side energized parts.

c. Panelboards – quantity of 1

d. Variable frequency drives – quantity of 1 label per section

e. Other stand-alone motor starters/controllers – quantity of 1 label per section

f. Automatic and manual transfer switches – quantity of 1

g. Enclosed circuit breakers – quantity of 1

2. Arc flash labels shall be thermal transfer type that is printed on adhesive backed polyester material. Labels shall be ANSI Z535.4 compliant, 4 inches tall by 6 inches wide, and provided with a 5-year warranty. For incident energy values of less than 40 cal/cm2, the labels shall have an orange-colored header with the word

“WARNING”. For incident energy values equal to and above 40 cal/cm2, the labels shall have a red-colored header with the word “DANGER”. Each label shall include the following information:

a. Equipment name

b. Date of issue and name of firm performing assessment

c. Incident energy

d. Working distance

e. Arc flash boundary

f. Nominal system voltage

3. A generic arc flash label that has a red-colored header with the word “DANGER” and text in large letters that shows “ENERGIZED WORK NOT PERMITTED” shall be provided for the following equipment:

a. Any equipment that requires an arc flash label (as specified above) that is located within a hazardous area.

b. Any equipment found to be in poor working condition, where in the judgement of the engineer performing the study, energized work should not

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be performed at all, regardless of the outcome of the incident energy analysis at that equipment.

c. Any equipment with a portable generator connection point.

3.08 STUDY REPORTS

A. The results of the studies shall be documented in a series of reports. A total of three (3) separate reports shall be provided as follows:

1. Preliminary Report – The Preliminary Report shall consist of all power systems studies as specified herein, with the following exceptions:

a. NFPA 70E energized electrical work permits shall not be included.

b. One (1) WARNING label and one (1) DANGER label shall be printed on plain paper for format review purposes only. Actual adhesive labels with calculated values shall not be included.

2. Pre-final Report – The Pre-final Report shall incorporate all comments received from the previous report review and shall include specific equipment data from the approved shop drawings of the proposed electrical equipment. The Pre-final

Report shall consist of all power systems studies as specified herein, with the following exceptions:

a. NFPA 70E energized electrical work permits shall not be included.

b. Sample arc flash hazard warning labels one (1) WARNING label and one (1)

DANGER label) shall be printed on the proposed adhesive material for review purposes.

3. Final Report – The Final Report shall consist of all power systems studies as specified herein, including final adhesive arc flash hazard warning labels. Final report shall incorporate all installed electrical equipment, including any field changes made during construction, and all comments received from the previous report review. All ‘as-left’ protective device settings shall be included in the report.

The Final Report shall bear the signature and seal of the professional electrical engineer that performed the study.

B. Hard copies of reports shall be furnished in the quantities specified herein, neatly organized into properly identified 3-ring binders. Tabs shall clearly separate each section of the report.

C. Electronic copies of reports shall be provided in PDF file format. Electronic copies shall have searchable text and bookmarks for each section of the report.

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D. Each report shall begin with a table of contents followed by an executive summary. The executive summary shall detail the configuration of the electrical system and summarize any concerns or recommendations for the electrical distribution system that resulted from the studies specified herein.

E. Reports shall include simplified single line diagrams with only the device name information displayed for all equipment, as well as single line diagrams with specific data displayed as specified herein for each study.

F. All data used in the reports such as conductor sizes and lengths, motor sizes, utility contribution information, fault analysis input, fault contributions, and the like shall be included in the appendices of the report.

G. All single line diagrams and time current curves shall be provided in the reports on

11x17 paper, properly folded to fit into the report binder. Use of standard 8.5x11 paper for these purposes is not permitted. Single line diagrams shall be appropriately split up between several sheets (if required) to allow the drawing scale to be adjusted as required to make text and symbols legible.

3.09 FIELD ADJUSTMENT

A. The SWITCHBOARD MANUFACTURER shall adjust all relay and other protective device settings according to the recommended settings table provided in the approved

Pre-Final Report.

B. The SWITCHBOARD MANUFACTURER shall make minor modifications to equipment as required to accomplish conformance with short circuit and protective device coordination studies.

3.10 ARC FLASH LABEL PLACEMENT

A. The SWITCHBOARD MANUFACTURER shall place approved adhesive arc flash labels on equipment after the Final Report is reviewed and approved.

3.11 TRAINING

A. The SWITCHBOARD MANUFACTURER shall train the Owner’s qualified electrical personnel of the potential arc flash hazards associated with working on energized equipment. The training shall be provided in two (2) separate sessions of no less than two (2) hours each. The training shall be certified for continuing education units (CEUs) by the International Association for Continuing Education Training (IACET), or equivalent. Training certificates shall be provided for all attendees.

END OF SECTION

APPENDIX A – SUPPLEMENTARY INFORMATION

REQUIRED DATABLOCK CONTENTS FOR POWER SYSTEM STUDIES

Component Type Input Data Load Flow Short Circuit TCC Plots*

Utility Nominal Voltage

Nominal Voltage

Current (A)

Power Factor

Power (kW)

Power (kVA)

Fault Contribution (3P RMS) and X/R Ratio

Fault Contribution (SLG RMS) and X/R Ratio N/A

Generator

Nominal Voltage

Rating (kW)

Power Factor

Voltage Drop (%)

Power Factor

Power (kW)

Power (kVA)

Fault Contribution (3P RMS)

Fault Contribution (SLG RMS)

FLA

Bus

Voltage

Manufacturer

SCCR

Voltage Drop (%)

Study Voltage

Current (A)

Power Factor

Power (kW)

Power (kVA)

Fault Magnitude (3P RMS)

Fault Magnitude (SLG RMS) N/A

Cable

Size (AWG or kcmil)

Parallel Sets

Length

Type (Cu/Al/Cu-Al)

Voltage Drop (%)

Current (A)

Power (kW)

Power (kVA)

Upstream Contribution (3P RMS)

Upstream Contribution (SLG RMS)

Downstream Contribution (3P RMS)

Downstream Contribution (SLG RMS)

N/A

Transformer

Rating (kVA)

Impedance (%Z)

X/R Ratio

Voltage Drop (%)

Sec. Current (A)

Power (kW)

Power (kVA)

Upstream Contribution (3P RMS)

Upstream Contribution (SLG RMS)

Downstream Contribution (3P RMS)

Downstream Contribution (SLG RMS)

N/A

Motor

Rating (hp)

Rated Voltage

FLA

Power Factor

Voltage Drop (%)

Study Voltage

Power Factor

Power (kW)

Power (kVA)

Upstream Contribution (3P RMS)

Upstream Contribution (SLG RMS)

FLA

LRA/FLA ratio

Non-Motor Load

Rating (A, kW, kVA)

Rated Voltage

Power Factor

Voltage Drop (%)

Study Voltage

Power Factor

Power (kW)

Power (kVA)

N/A N/A

Fuse

Manufacturer

Model

Rating (A)

N/A N/A Same as Input Data

Relay**

Manufacturer

Model

CT Ratio

Curve Elements & Settings

N/A N/A Same as Input Data

Disconnect Switch Manufacturer

SCCR (kA) N/A N/A N/A

Circuit Breaker

(no integral trip unit)

Manufacturer

SCCR (kA) N/A N/A N/A

Circuit Breaker***

(all others)

Manufacturer

Model

SCCR (kA)

Frame/Sensor/Plug Ratings

Settings***

LTPU

[LTD Curve Shape]

[LTD]

[STPU]

[STD and I2T On/Off]

INST

[GFPU]

[GFD and I2T On/Off]

[AF Maint. Setting/Curve]

N/A N/A Same as Input Data

Motor Circuit

Protector

Manufacturer

Model

SCCR (kA)

Frame/Trip Ratings

N/A N/A Same as Input Data

Motor Overload Relay

Manufacturer

Model

SCCR (kA)

Frame/Trip Ratings

Settings

N/A N/A Same as Input Data

* TCC single line diagrams shall not display datablocks.

** Complex and/or non-overcurrent settings for multifunction relays (e.g. bus/winding differential, motor thermal model parameters, under/overvoltage, RTD alarm and trip setpoints, etc.) are excluded from the model.

*** Hide setting elements where not applicable for a given circuit breaker. Recommended settings for non-overcurrent settings for electronic trip circuit breakers

(e.g. under/overvoltage, zone-selective interlocking, alarm setpoints, etc.) are excluded from the model.

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SECTION 26 09 16

ELECTRIC CONTROLS AND RELAYS

PART 1 – GENERAL

1.01 THE REQUIREMENT

A. The SWITCHBOARD MANUFACTURER shall furnish, install, test, and place in satisfactory operation all electric controls and relays as specified herein and indicated on the Drawings.

B. Electrical control and relay systems shall be assembled using NEMA rated components.

Components designed and built to International Electrotechnical Commission (IEC) standards are not recognized. Equipment designed, manufactured, and Labeled in compliance with IEC standards is not acceptable.

1.02 CODES AND STANDARDS

A. Products specified herein shall be designed, manufactured, and/or Listed to the following standards as applicable:

1. National Electrical Manufacturers Association (NEMA):

a. NEMA 250 – Enclosures for Electrical Equipment.

2. National Fire Protection Association (NFPA):

a. NFPA 70 – National Electrical Code (NEC).

3. Underwriters Laboratories (UL):

a. UL 508A – Standard for Industrial Control Panels.

b. UL-1203 – Standard for Explosion-proof and Dust-ignition-proof Electrical

Equipment for use in Hazardous (Classified) Locations.

1.03 SUBMITTALS

A. In accordance with the procedures and requirements set forth in the General Conditions, the SWITCHBOARD MANUFACTURER shall obtain from the equipment manufacturer and submit the following:

1. Shop Drawings

2. Spare Parts List

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B. Each submittal shall be identified by the applicable Specification Section.

1.04 SHOP DRAWINGS

A. Each submittal shall be complete in all respects, incorporating all information and data listed herein and all additional information required for evaluation of the proposed equipment's compliance with the Contract Documents.

B. Partial, incomplete, or illegible submittals will be returned to the SWITCHBOARD

MANUFACTURER without review for resubmittal.

C. Shop drawings shall include but not be limited to:

1. Product data sheets.

D. The shop drawing information shall be complete and organized in such a way that the

Engineer can determine if the requirements of these Specifications are being met.

Copies of technical bulletins, technical data sheets from "soft-cover" catalogs, and similar information which is "highlighted" or somehow identifies the specific equipment items the SWITCHBOARD MANUFACTURER intends to provide are acceptable and shall be submitted.

PART 2 – PRODUCTS

2.01 CONTROL COMPONENTS

A. Manufacturers

1. Control components shall be manufactured by Eaton, The Square D Company, GE by ABB, Allen-Bradley, Siemens Energy and Automation, or Engineer approved equal.

B. Pilot Devices

1. General

a. All pilot devices shall be provided with a legend plate. Legend plates shall have a white background and black lettering and indicate the function of the respective pilot device. The text shown on the Drawings or indicated in the specifications shall be used as the basis for legend plate engraving (e.g., HAND-OFF-AUTO, RUN, EMERGENCY STOP, etc.).

b. All pilot devices shall be selected and properly installed to maintain the

NEMA 250 rating of the enclosure in which they are installed. All pilot devices shall be UL 508 Listed.

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c. All pilot devices shall be 30.5mm in diameter, unless otherwise indicated.

22mm devices are not acceptable.

d. Pilot devices for all electrical equipment under this Contract shall be of the same type and manufacturer unless otherwise specified herein or indicated on the Drawings.

2. Pushbuttons

a. Pushbuttons shall be non-illuminated, black in color, and have momentary style operation unless otherwise indicated on the Drawings.

b. Pushbuttons shall have the quantity of normally closed and/or normally open contacts as indicated on the Drawings and as required. In addition to the required contacts, one (1) spare normally open and one (1) spare normally closed contact shall be installed at each pushbutton. Contacts shall be rated for 5A at 250VAC/DC (minimum), but no less than required for the application.

c. Pushbuttons shall be provided with a full guard around the perimeter of the button. Where a lockout style pushbutton is specified or indicated on the

Drawings, provide a padlockable guard.

3. Selector Switches

a. Selector switches shall be non-illuminated, black in color, and have the number of maintained positions as indicated on the Drawings and as required. Handles shall be the extended type that provide a greater surface area for operation.

b. Selector switches shall have the quantity of normally closed and/or normally open contacts as indicated on the Drawings and as required. In addition to the required contacts, one (1) spare normally open and one (1) spare normally closed contact shall be installed at each selector switch. Contacts shall be rated for 5A at 250VAC/DC (minimum), but no less than required for the application.

c. Where indicated in the Drawings or Specifications, provide spring return positions.

d. Selector switches shall be provided with an indexing component that fits into the keyed portion of the cutout for the device and prevents the switch from spinning when operated.

4. Indicating Lights

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a. Indicating lights shall be LED type, with the proper voltage rating to suit the application, and push-to-test feature.

b. Indicating light lens colors shall be as required in equipment specifications and/or as indicated on the Drawings. If lens colors are not indicated, the following colors shall be used:

Color Designation

Red "Run", "On", “Open”

Green "Off", “Closed”

Amber "Alarm", "Fail"

White “Control Power On”

5. Emergency Stop and Tagline Switches

a. Emergency stop switches shall be non-illuminated, red in color, with a minimum 35mm diameter mushroom head. Once activated, switch shall maintain its position and require a manual pull to release/reset.

b. Tagline switches shall have a plunger that activates upon tension from the associated safety cable. Once activated, switch shall maintain its position and require a manual release/reset.

c. Emergency stop and tagline switches shall have the quantity of normally closed and/or normally open contacts as indicated on the Drawings and as required. In addition to the required contacts, one (1) spare normally open and one (1) spare normally closed contact shall be installed at each switch.

Contacts shall be rated for 5A at 250VAC/DC (minimum), but no less than required for the application.

C. Relays and Timers

1. General

a. Relays and timers shall be furnished with an integral pilot light for positive indication of coil energization.

b. Relays and timers shall have tubular pin style terminals with matching 11-pin

DIN rail mount socket. Spade or blade style terminals are not acceptable.

c. Relays and timers for all electrical equipment under this Contract shall be of the same type and manufacturer unless otherwise specified herein or indicated on the Drawings.

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2. Control and Pilot Relays

a. Relays shall have a clear or translucent housing that allows the contacts to be visually inspected without disassembly.

b. Relays shall have coil voltage as required to suit the application and/or as indicated on the Drawings.

c. Relays shall be provided with contacts rated for 10A (resistive), minimum, at

120/240 VAC and 28 VDC. Relays shall have 3-pole, double-throw (3PDT) contact arrangement.

3. Time Delay Relays

a. Timers delay relays shall utilize electronic timing technology. Mechanical timing devices are not acceptable.

b. Relays shall have coil voltage as required to suit the application and/or as indicated on the Drawings.

c. Relays shall be provided with contacts rated for 10A (resistive), minimum, at

120/240 VAC and 28 VDC. Relays shall have double-pole double-throw

(DPDT) contact arrangement.

d. Time delay ranges shall be as indicated on the Drawings and/or as required to suit the application. Timing range shall be adjustable from the front of the relay. On delay and off delay timer configurations shall be provided as indicated on the Drawings and/or as required to suit the application.

4. Elapsed Time Meters

a. Elapsed time meters shall be non-resettable type with no less than a four (4) digit display. Coil voltage shall be as required to suit the application and/or as indicated on the Drawings.

D. Control Terminal Blocks

1. Control terminal blocks shall be assembled on non-current carrying galvanized steel DIN mounting rails securely bolted to the enclosure or subpanel. Terminals shall be tubular screw type with pressure plate that will accommodate wire size range of #22 – #8 AWG.

2. Control terminal blocks shall be single tier with a minimum rating of 600 volts and

20A. Separate terminal strips shall be provided for each type of control used (e.g., 120VAC vs. 24VDC). Quantity of terminals shall be provided as required to suit the application. In addition, there shall be a sufficient quantity of terminals for the termination of all spare conductors.

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3. Terminals shall be marked with a permanent, continuous marking strip, with each terminal numbered. One side of each terminal shall be reserved exclusively for incoming field conductors. Common connections and jumpers required for internal wiring shall not be made on the field side of the terminal.

PART 3 – EXECUTION

3.01 INSTALLATION

A. All control components shall be mounted in a manner that will permit servicing, adjustment, testing, and removal without disconnecting, moving, or removing any other component. Components mounted on the inside of panels shall be mounted on removable plates and not directly to the enclosure. Mounting shall be rigid and stable unless shock mounting is required otherwise by the manufacturer to protect equipment from vibration. Component's mounting shall be oriented in accordance with the component manufacturer's and industries' standard practices.

B. Pilot devices shall be properly bonded to the equipment enclosure door where they are installed. If proper bonding cannot be achieved through the locknuts that affix the device in place, a green colored bonding screw shall be provided on the pilot device. The device shall be bonded to the equipment enclosure with an insulated green bonding conductor.

C. Terminal strips, relays, timers, and similar devices shall not be installed on the rear or side of the panel/cabinet doors.

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SECTION 26 24 13

LOW VOLTAGE SWITCHBOARDS

PART 1 – GENERAL

1.01 SUMMARY

A. Definitions

1. SWITCHBOARD MANUFACTURER (manufacturer) – The entity responsible for furnishing of equipment specified in this section, and responsible for manufacturing, factory testing, and warrantying the low voltage switchboards.

B. Scope

1. This section specifies the requirements for providing two (2) complete and operable low voltage switchboards.

2. SWITCHBOARD MANUFACTURER shall provide equipment in conformance to the specified requirements. The furnished equipment shall be subject to review for all applicable permits, inspection, and approval by the proper authorities in local jurisdiction of such work. SWITCHBOARD MANUFACTURER shall provide all switchboard equipment production model technical information necessary for others to apply for permits, inspections, and approvals. The local jurisdictions are the City of Homestead, Miami-Dade County, and the State of Florida.

3. The SWITCHBOARD MANUFACTURER shall verify that all devices necessary for a properly functioning switchboard, as specified herein, have been provided.

1.02 THE REQUIREMENT

A. The SWITCHBOARD MANUFACTURER shall furnish in satisfactory operation the low voltage switchboards (SWBDs) as specified herein and indicated on the Drawings.

B. Reference the following Specification Sections:

1. Section 26 09 16 – Electric Controls and Relays

2. Section 26 43 13 – Surge Protective Devices

C. The SWBD line-ups shall contain circuit breakers, metering equipment, control devices, and all accessories as specified herein, indicated on the Drawings, and as required to result in a complete and operable power distribution equipment assembly.

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D. The SWITCHBOARD MANUFACTURER shall also manufacture the structure and major equipment components, which includes, but is not limited to, circuit breakers, power monitoring equipment, meters, relays, instrument transformers, controls, ATC, and other components of the equipment assembly. Sub-contracting of wiring is not acceptable.

E. The SWBDs shall be assembled using NEMA rated components. Components designed and built to International Electrotechnical Commission (IEC) standards are not recognized. Equipment designed, manufactured, and labeled in compliance with IEC standards is not acceptable.

F. The low voltage switchboards and all associated equipment furnished under this section shall comply with all applicable Build America, Buy America (BABA) requirements.

G. Materials and equipment shall be delivered to the job site factory tested and ready for installation. The SWITCHBOARD MANUFACTURER may be required to store and maintain the low voltage switchboards until the site is ready for delivery. Three (3) months of storage shall be considered for bid purposes. The SWITCHBOARD

MANUFACTURER shall provide full insurance coverage for all equipment until its arrival at the job site.

1.03 CODES AND STANDARDS

A. All equipment shall be Listed by and shall bear the Label of Underwriter's Laboratories, Incorporated (UL).

B. The equipment shall be designed, manufactured, and/or Listed to the following standards as applicable:

1. American National Standards Institute (ANSI)/Institute of Electrical and Electronic

Engineers (IEEE):

a. ANSI/IEEE C12.1 – Code for Electricity Metering.

b. ANSI/IEEE C57.13 – Instrument Transformers.

2. National Electrical Manufacturers Association (NEMA):

a. NEMA PB 2 – Deadfront Distribution Switchboards.

3. National Fire Protection Association (NFPA):

a. NFPA 70 – National Electrical Code (NEC).

4. Underwriters Laboratories (UL):

a. UL 98 – Enclosed and Dead -Front Switches.

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b. UL 489 – Molded Case Circuit Breakers, Molded Case Switches, and Circuit

Breaker Enclosures.

c. UL 891 – Switchboards.

d. UL 1066 – Low-Voltage AC and DC Power Circuit Breakers Used in

Enclosures.

1.04 SUBMITTALS

A. In accordance with the procedures and requirements set forth in the General Conditions, the SWITCHBOARD MANUFACTURER shall submit the following:

1. Shop Drawings

2. Operation and Maintenance Manuals

3. Spare Parts List

4. Proposed Testing Methods

5. Reports of Certified Shop and Field Tests

6. Manufacturer’s Representatives Installation Certification

7. Functional Testing Plan for Automatic Transfer Controls

B. Each submittal shall be identified by the applicable Specification Section.

1.05 SHOP DRAWINGS

A. Each submittal shall be complete in all respects, incorporating all information and data listed herein and all additional information required for evaluation of the proposed equipment's compliance with the Contract Documents.

B. Partial, incomplete, or illegible submissions will be returned to the SWITCHBOARD

MANUFACTURER without review for resubmittal.

C. Shop drawings for each SWBD assembly shall include but not be limited to:

1. A Compliance, Deviations, and Exceptions (CD&E) letter. If the shop drawings are submitted without this CD&E letter, the submittal will be rejected. The letter shall include all comments, deviations, and exceptions taken to the Drawings and

Specifications by the SWITCHBOARD MANUFACTURER AND Equipment

Manufacturer/Supplier. This letter shall include a copy of this Specification Section.

In the left margin beside each and every paragraph/item, a letter "C", "D", or "E" shall be typed or written in. The letter "C" shall be for full compliance with the

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requirement. The letter "D" shall be for a deviation from the requirement. The letter

"E" shall be for taking exception to a requirement. Any requirements with the letter

"D" or "E" beside them shall be provided with a full typewritten explanation of the deviation/exception. Handwritten explanation of the deviations/exceptions is not acceptable. The CD&E letter shall also address deviations and exceptions taken to each Drawing related to this Specification Section.

2. Bill of material list for each SWBD assembly including each SWBD compartment.

3. Equipment specifications and product data sheets identifying all electrical ratings.

This information shall include all equipment and devices comprising the SWBD.

4. Complete assembly, layout, anchoring, and installation drawings with clearly marked dimensions. Plan, front, and side view drawings, including overall dimensions of the SWBD assembly. Identify shipping splits and show conduit stub-up area locations on the Drawings.

5. Approximate total shipping weight of each shipping split and/or equipment assembly, and total assembled equipment line-up weight.

6. Complete, custom one-line diagram and complete three-line diagram for the

SWBD line-up. The diagrams shall indicate the devices comprising the SWBD assembly including, but not limited to, circuit breakers, control power and instrument transformers, meters, relays, control devices, and other equipment comprising the complete assembly. Clearly indicate electrical ratings of all devices.

7. Complete, custom internal wiring diagram of each SWBD compartment/assembly.

Each wiring diagram shall include wire identification and terminal numbers.

8. Internal compartment-to-compartment interconnection wiring diagrams including wiring identification and terminal numbers.

9. Example equipment nameplate data sheet.

10. Nameplate schedule for each compartment.

11. Key interlock scheme drawing and sequence of operations.

12. Manufacturer's installation instructions.

13. Manufacturer's written warranty statement.

D. The shop drawing information shall be complete and organized in such a way that the

Engineer can determine if the requirements of these specifications are being met.

Copies of technical bulletins, technical data sheets from "soft-cover" catalogs, and similar information which is "highlighted" or somehow identifies the specific equipment

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items the SWITCHBOARD MANUFACTURER intends to provide are acceptable and shall be submitted.

1.06 OPERATIONS AND MAINTENANCE MANUALS

A. The SWITCHBOARD MANUFACTURER shall submit operation and maintenance manuals in accordance with the procedures and requirements set forth in the General

Conditions. The manuals shall include:

1. Instruction books and/or leaflets.

2. Spare parts list.

3. Final as-built construction drawings (updated from those included in the shop drawings) incorporating all changes made in the manufacturing and installation process.

4. All other drawings, product information, and other materials originally included in the shop drawings, updated as necessary to reflect as-built conditions.

1.07 SPARE PARTS

A. The SWBDs shall be furnished with all spare parts as recommended by the equipment manufacturer. Spaces in SWBDs shall be furnished with installed spare circuit breakers where indicated on the Drawings.

B. In addition to the spare parts recommended by the manufacturer, the SWITCHBOARD

MANUFACTURER shall furnish the following minimum spare parts for each SWBD assembly:

Number

Required Description

1 set Fuses of each size and type provided.

1 Control power transformer of each size and type provided.

1 Lamps and lenses for indicating lights, each color.

1 Indicating lamp sockets for each type provided.

Pilot devices (e.g., pushbutton, selector switch, etc.) complete with contact blocks and legend plates for each type, color, size, and rating provided.

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1.08 IDENTIFICATION

A. Each SWBD line-up shall be identified with the identification name and/or number indicated on the Drawings (e.g., SWBD-DIST). A nameplate shall be securely affixed in a conspicuous place on the SWBD. Nameplates shall be as specified herein.

1.09 WARRANTY

A. SWITCHBOARD MANUFACTURER shall warrant that the material and workmanship of all components and the operation of the equipment is in accordance with the latest design practices and meets the requirements of this Specification.

B. Warranty shall include, but not be limited to the following:

1. Replace equipment/components found to be faulty, make changes in equipment arrangement, and/or make adjustments necessary to meet the equipment or functional requirements of this Specification.

2. System rewiring and component substitution/rebuild.

3. All accessories and appurtenances provided by the equipment manufacturer.

C. Warranty for each SWBD line-up shall be in effect for a period of 24 months following final acceptance of the SWBD.

PART 2 – PRODUCTS

2.01 MANUFACTURERS

A. The equipment covered by these specifications is intended to be standard equipment of proven performance as manufactured by reputable concerns. Equipment shall be designed, constructed, and installed in accordance with the best practices of the trade, and shall operate satisfactorily when installed as shown on the Drawings.

B. It is the intent of these specifications that the SWBDs be manufactured and assembled by a single manufacturer who shall be responsible for matching all components and providing equipment which functions together as a system. Subcontracting of wiring and/or third-party assembly is not acceptable.

C. The SWBDs shall be Pow-R-Line Xpert (PRLX) as manufactured by Eaton, Reliagear

LVSB by ABB, QED-2 LV Series as manufactured by The Square D Company, or

Siemens Energy & Automation, Inc. equivalent.

2.02 SWITCHBOARDS

A. General

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1. SWBD assemblies shall be UL 891 Listed and bear a UL label indicating the UL

File Number. Where indicated on the Drawings, SWBD shall be suitable for use as service equipment and shall be marked as such externally on the equipment enclosure.

2. The SWBD manufacturer shall provide all of the proper cable lugs for all cable connections as required to avoid field modifications. Cable lugs for connecting to

SWBD bus and/or circuit breakers 1600A and larger shall be…