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Project Number: 228730 WWTE SCADA Upgrades
Issue Date: August 2017 Nashua, NH

panel and panel board with connections to other equipment where specifically
indicated and noted.

C. Bonding conductors shall be continuous where possible. Where splices are
required, provide compression connectors of approved pattern. Insulate
connectors to equivalent thickness of conductors.

D. Provide grounding system for grounded circuit conductors of dry type transformer
secondaries in accordance with NEC. Use exothermic style ground connections to
building steel. Enclose grounding conductors in schedule 40 PVC conduit.

E. Provide equipment grounding conductors in all conduits containing power,
control, or instrumentation conductors on the load side of the service equipment
or on the load side of a separately derived system.

F. Comply with NEC Article 250 for sizes and quantities of equipment grounding
conductors, except that larger sizes indicated or shown on the Contract
Documents shall take precedence. Use of metallic conduit systems for equipment
grounding as recognized by the NEC shall not be permitted under this
specification.

G. Install grounding bushings on conduits at both primary and secondary entrances
to transformers. Ground transformer enclosures to bushings.

H. Install bonding jumper for flexible metal conduit unless fittings are approved for
grounding or otherwise comply with NEC.

1. Size jumper to match over-current device.
2. Green insulation.
3. Connect to grounding bushing at each end.
I. Ensure that entire electrical system is electrically continuous and permanently and

effectively grounded, including all electrical equipment and motors.

1. Locate ground rods with a minimum of two rod length from each other
and at least the same distance from any other grounding electrode.
Connect ground conductors to ground rods by means of exothermic welds
except at test wells and as otherwise indicated. Drive rods until tops are
24 inches below finished floor or final grade except as otherwise
indicated.

J. Route grounding electrode conductors along the shortest and straightest paths
possible without obstructing access or placing conductors where they may be
subjected to strain, impact, or damage, except as indicated.

K. Ensure ground rod(s) installation does not interfere with or puncture landfill cap.

GROUNDING AND BONDING FOR ELECTRICAL SYSTEMS
WOODARD & CURRAN 26 05 26-3

Project Number: 228730 WWTE SCADA Upgrades
Issue Date: August 2017 Nashua, NH

3.02 BONDING FOR OTHER TRADES

A.

Signal raceways, water piping, heating piping and metallic air ducts shall be
bonded together and to the grounding conductor with No. 8 soft drawn bare solid
conductors. Connections to pipes shall be made with cast clamps of like material
as the pipes to which attached, to ducting terminated in a secure manner by best
practical means, bonding across any flexible or insulated connections.

All bonding conductors shall be installed in a neat manner properly shaped for
contour of surface involved and properly supported. At locations remote from the
main service entrance panel boards, bond to the largest raceway nearby.

3.03 FIELD TESTING

A.

Measure ground resistance without the soil being moistened by any means other
than natural precipitation or natural drainage or seepage and without chemical
treatment or other artificial means of reducing natural ground resistance. Perform
tests by the three-point fall of potential method in accordance with Section 9.03 of
IEEE 81. Simple moisture addition is not acceptable.

Ground/resistance maximum values shall be as follows:

1. Equipment rated 500 kva and less: 10 ohms.

2. Equipment rated 500 kVA to 1000 Kva: 5 ohms.

3. Equipment rated over 1000 kVA: 3 ohms.

4. Unfenced substations and pad mounted equipment: 5 ohms.
5. Fence Grounds: 10 ohms.

Where ground resistances exceed specified values, and if directed, modify the
grounding system to reduce resistance values.

END OF SECTION

GROUNDING AND BONDING FOR ELECTRICAL SYSTEMS

WOODARD & CURRAN 26 05 26-4

Project Number: 228730 WWTE SCADA Upgrades
Issue Date: August 2017 Nashua, NH

SECTION 26 05 34

RACEWAYS, BOXES AND SUPPORTING DEVICES

PART 1 - GENERAL

1.01 DESCRIPTION OF WORK

A.

The Contractor shall provide the labor, tools, equipment, and materials necessary
to furnish and install raceways, boxes and supporting devices in accordance with
the plans and as specified herein.

Types of products specified in this section include:

1. Conduit, Raceways & Fittings
2. Supporting Devices
3. Boxes and fittings

1.02 RELATED DOCUMENTS

A.

Drawings and general provisions of the Contract, including General and
Supplementary Conditions apply to this section.

Related Sections

1. Division 26: Section 26 05 00 COMMON WORK RESULTS FOR
ELECTRICAL

2. Division 26: Section 26 05 19 LOW-VOLTAGE ELECTRICAL POWER
CONDUCTORS AND CABLES

1.03 QUALITY ASSURANCE

A.

B.

Reference Standards.

UNDERWRITER'S LABORATORIES, INC. (UL) LISTING AND LABELING
1. Items provided under this section shall be listed and labeled by UL.
NATIONAL ELECTRICAL CODE (NEC)

NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)

RACEWAYS, BOXES AND SUPPORTING DEVICES

WOODARD & CURRAN 26 05 34-1

Project Number: 228730 WWTE SCADA Upgrades
Issue Date: August 2017 Nashua, NH
1.04 SUBMITTALS
A. Furnish manufacturer's product data, test reports, and material certifications as
required.
1. Product data for cabinets and enclosures with classification higher than
NEMA 1.
2. Shop drawings for floor boxes and boxes, enclosures and cabinets that are
to be shop fabricated (non-stock items).
PART 2 - PRODUCTS
2.01 CONDUIT, RACEWAYS & FITTINGS
A. Provide conduit with %4-inch diameter minimum, except where specifically shown
smaller on the Contract Drawings.
B. Conduit, connectors, and fittings shall be approved for the installation of electrical

conductors.

C. Refer to Table 3.01A for approved conduit installation guidelines.

1. Electrical Metallic Tubing (EMT)

a.

EMT shall be rigid metallic conduit of the thinwall type in straight
lengths, elbows, or bends and must conform to NEMA C80.3 and
the requirements of UL 797.

Couplings and connectors shall be steel compression fittings.
Where EMT enters outlet boxes, cabinets, or other enclosures,
connectors must be the insulated-throat type, with a locknut.
Fittings must meet the requirements of NEMA FB 1.

2. Rigid Galvanized Steel Conduit

a.

WOODARD & CURRAN

Rigid steel conduit (RGS), including couplings, elbows, bends, and
nipples, shall conform to the requirements of UL 6 and NEMA
C80.1 Steel fittings shall be galvanized by the hot-dip process.

Fittings for rigid steel conduit shall be threaded and shall conform
to NEMA FB 1.

Gaskets shall be solid for fittings sized 1-1/2 inches and less.
Conduit fittings with blank covers shall have gaskets except in
clean, dry areas or at the lowest point of a conduit run where
drainage is required.

RACEWAYS, BOXES AND SUPPORTING DEVICES
26 05 34-2

Project Number: 228730
Issue Date: August 2017

WWTE SCADA Upgrades
Nashua, NH

Covers shall have captive screws and be accessible after the Work
has been completed.

3. Rigid Aluminum Conduit

a.

RAC, including couplings, elbows, bends, and nipples, shall
conform to the requirements of UL 6 and ANSI C80:5.

Fittings for rigid aluminum conduit shall be threaded and shall
conform to NEMA FB 1. Fittings shall be galvanized by the hot
dip process, unless manufacturer dictates aluminum for specific
application.

Gaskets shall be solid for fittings sized 1-1/2 inches and less.
Conduit fittings with blank covers shall have gaskets except in
clean, dry areas or at the lowest point of a conduit run where
drainage is required.

Covers shall have captive screws and be accessible after the work
has been completed.

4. PVC-Coated Rigid Metal Conduit

a.

Rigid galvanized metal conduit coated with 40 mils thick
polyvinylchloride coating.

Fittings, elbows, supporting devices and accessories shall include
factory applied 20 mils thick polyvinylchloride coating and be
manufactured by the same as that of the conduit.

Use tools as recommended by the manufacturer so as not to
damage PVC coating. Where coating is damaged, touch-up with
PVC paint in the field after installation.

5. Rigid Plastic Conduit

a.

PVC Schedule 40: Conduit shall be made of polyvinyl chloride
compound that shall be homogeneous plastic material free from
cracks, holes or foreign inclusions. Conduit shall be rated for use
with 90 degree C conductors, UL Listed. Use solvent cement to
join conduits as manufactured the same as the conduit
manufacturer.

PVC Schedule 80: Heavy wall PVC conduit that shall be made of
polyvinyl chloride compound that shall be homogeneous plastic
material free from cracks, holes or foreign inclusions. Conduit
shall be rated for use with 90 degree C conductors, UL Listed. Use
solvent cement to join conduits as manufactured the same as the
conduit manufacturer.

6. Flexible Metallic Conduit

WOODARD & CURRAN

RACEWAYS, BOXES AND SUPPORTING DEVICES
26 05 34-3

Project Number: 228730
Issue Date: August 2017

WWTE SCADA Upgrades
Nashua, NH

Flexible metallic (FM) conduit shall meet the requirements of UL1.

Liquidtight flexible metallic conduit shall be provided with a
protective jacket of PVC extruded over a flexible interlocked
galvanized steel core to protect wiring against moisture, oil,
chemicals, and corrosive fumes.

Fittings for flexible metallic conduit shall meet the requirements of
UL 514B, Type I box connector, electrical, Type II coupling,
electrical conduit, flexible steel, or Type IV adapter, electrical
conduit.

7. Wireways

a.

Wireways and auxiliary gutters for use in exposed, dry locations
shall be a prefabricated channel-shaped sheet metal trough with
hinged or removable covers, associated fittings, and supports for
housing, and protecting electrical wires and cables in accordance
with UL 870.

Straight sections of trough, elbows, tees, crosses, closing plates,
connectors, and hanging brackets shall be constructed from sheet
steel of commercial quality not less than 16-gage. Sheet metal
component parts shall be cleaned, phosphatized, and coated with a
corrosion-resistant gray paint.

Straight sections of wireways and auxiliary gutters shall be solid or
have knockouts as indicated in both sides and bottom, 3 inches on
center.

Straight sections shall be not more than 5-feet long, with covers
held closed with screws.

8. Conduit Seals

WOODARD & CURRAN

Provide factory fabricated watertight conduit sealing bushing
assemblies suitable for sealing around conduit, or tubing passing
through concrete floors and walls. Provide a cast in place water
stop wall sleeve with a mechanical pipe seal between the conduit
and the sleeve. Construct seals with steel sleeve, malleable iron
body, neoprene sealing grommets or rings, metal pressure rings,
pressure clamps, and cap screws.

Provide E.Y-S. seal fittings with appropriate potting material where
conduits enter or leave a Class 1, Division 1 or 2 environments or a
Class 2, Division | or 2 environment.

RACEWAYS, BOXES AND SUPPORTING DEVICES
26 05 34-4

Project Number: 228730

WWTE SCADA Upgrades

Issue Date: August 2017 Nashua, NH
2.02 SUPPORTING DEVICES
A. Supports, support hardware, and fasteners shall be protected with zinc coating or

with treatment of equivalent corrosion resistance using approved alternative
treatment, finish, or inherent material characteristic. Products for use outdoors
shall be hot dip galvanized unless material is inherently corrosion resistant.

B. Refer to Table 2.02A for approved supporting device installation guidelines.

1. Conduit Supports

a.

Single run hangers: Galvanized steel conduit straps or clamps, or
cast metal beam clamps. Perforated straps and spring steel clips
and clamps will not be permitted.

Group run hangers: Minimum 12-gauge galvanized performed U-
channel rack with conduit fittings; 25 percent spare capacity.

Hanger rods: Threaded steel, 3/8-inch diameter, or as identified on
the Drawings.

Vertical run supports: Minimum 12-gauge galvanized performed
U-channel struts with conduit fittings.

2. Equipment and Lighting Supports

a. U-channel: 12-gauge galvanized performed U-channel struts with
fixture and conduit fittings, as applicable, unless indicated
otherwise on the Drawings.

3. Corrosive Area Supports

a. Clamp Hangers, Pipe Straps, and Clamp Back Spacers for use with
PVC-coated rigid metal conduit shall have 40mil gray PVC
exterior coating.

b. Clamp Hangers, Pipe Straps, etc. for use with PVC nonmetallic
conduit shall be of nonmetallic PVC material.

C. Hanger Rods: 20mil gray PVC exterior coated rod with threaded
ends only 3/8” and 1/2” sizes as required.

d. Strut Support: 20mil gray PVC exterior coating strut. Standard

WOODARD & CURRAN

channel, slotted channel, and back to back channel are acceptable.

RACEWAYS, BOXES AND SUPPORTING DEVICES
26 05 34-5

Project Number: 228730 WWTE SCADA Upgrades
Issue Date: August 2017 Nashua, NH

e. Provide Stainless steel hangers, rods and supports in lieu of PVC
coated when indicated in the Supporting Devices Table below.

TABLE 2.02A — Supporting Devices

Location/Equipment Acceptable Support Type

Exterior Galvanized Steel U-Channel

2.03 BOXES AND FITTINGS

A. Boxes must have sufficient volume to accommodate the number of conductors
entering the box in accordance with the requirements of NFPA 70 and UL 514A.

B. In general, boxes that are exposed to weather, process areas, normally wet
locations, and locations exposed in mechanical spaces shall be cast-metal. Boxes
in all other finished areas shall be sheet metal. Boxes installed in corrosive areas,
such as the chemical feed room, shall be nonmetallic.

C. Refer to Table 2.03A for approved enclosure types.

1. Sheet Metal Outlet Boxes

a. Sheet Metal Outlet Boxes: Standard type galvanized steel,
minimum four inch square or octagon by 1-1/2 inch deep.

b. Luminaire and Equipment Supporting boxes: Rated for weight of
equipment supported; include 2 inch male fixture studs where
required.

C. Single Wall Type: Minimum size, four inch square by 1-1/2 inch or

2-1/8 inch deep, except as noted. Provide dry wall device covers
raised 3/4 inch minimum to insure flush finish mounting.

d. Ganged Wall Type: Minimum depth three inches except as noted,
ganged as required under common plate to contain devices shown.
On 277 volt circuits ganged boxes for switches shall contain only
one circuit or equip box with permanent barriers per NEC Art 404-
8.

2. Cast Outlet Boxes

Type FS shallow and type FD deep, cast ferroalloy.

b. Provide number of threaded hubs as required.
C. Use in all exterior, damp and locations exposed in mechanical
spaces.

RACEWAYS, BOXES AND SUPPORTING DEVICES
WOODARD & CURRAN 26 05 34-6

Project Number: 228730
Issue Date: August 2017

WWTE SCADA Upgrades
Nashua, NH

d. Provide gasketed cover and accessories by box manufacturer for
complete weatherproofing. Provide correct box to accept
weatherproof covers as specified.

3. Sheet Metal Pull & Junction Boxes

a. Sheet metal boxes shall be standard type galvanized steel and must
conform to UL 50.

b. Box dimensions shall be minimum four inch square or octagon by
2/1/2 inch deep.

C. Sizes up to 12x12x6 inch: Provide screw-type or hinged covers.

d. Sizes greater than 12x12x6 inch: Provide hinged covers.

e. Boxes shall be sized to accommodate all incoming raceways.

4. Nonmetallic Outlet, Device, and Wiring Boxes

a. Conform to NEMA OS 2, "Nonmetallic Outlet Boxes, Device
Boxes, Covers, and box Supports," and UL 514C, "Nonmetallic
Outlet Boxes, Flush Device Boxes and Covers." Boxes shall be
molded polyvinyl chloride (PVC), or fiberglass units of type,
shape, size, and depth to suit location and application.

b. Boxes shall be equipped with threaded screw holes for device and

WOODARD & CURRAN

cover plate mounting. Each box shall have a molded cover of
matching material suitable for the application and location
installed.

RACEWAYS, BOXES AND SUPPORTING DEVICES
26 05 34-7

Project Number: 228730
Issue Date: August 2017

WWTE SCADA Upgrades
Nashua, NH

TABLE 2.03A — Electrical Enclosure Types

Location/Equipment Acceptable Enclosure Type
Exterior (unclassified) NEMA 4X
NEMA 7 (Explosion Proof)
Class 1 Division 1, Division 2 Locations NEMA 4X for Intrinsically Safe
Equipment

PART 3 —- EXECUTION

3.01 CONDUIT

A. Uses Permitted

1.

Use liquid tight flexible metal conduit for the final 24 inches of
connections to motors or control items subject to movement or vibration.

Use RGS for all exterior aboveground installations unless otherwise noted.

Use PVC coated rigid steel conduit, or as scheduled below, for installation
in corrosive areas, and other areas as identified on the Contract Drawings.

Use Schedule 80 PVC conduit for all underground installations. The
transition from underground and from sand-encasement to riser shall be
PVC coated rigid steel conduit to a minimum of 12” above finished grade
elevation. All elbows shall be prefabricated Rigid Steel to prevent wire
burn through. Reference specification 26 05 43 “Underground Ducts and
Raceways for Electrical Systems” for further requirements.

Install conduit seals for conduit penetrations of slabs on grade and exterior
walls below grade and where indicated. Tighten sleeve seal screws until
sealing grommets have expanded to form watertight seal. Provide seals
for the interior of conduits that penetrate exterior or water bearing walls,
consisting of gland type sealing bushings or RTV closed cell silicone
foam. Refer to Table 3.01A below for approved conduit types:

TABLE 3.01A — Conduit Types

Location/Equipment Approved Conduit Type

Exterior Rigid Galvanized Steel

B. Power,
and all

lighting, control, emergency light and power, and special-service systems
related components shall be installed in accordance with NFPA 70, and

RACEWAYS, BOXES AND SUPPORTING DEVICES

WOODARD & CURRAN 26 05 34-8