Project Number: 228730 WWTE SCADA Upgrades
Issue Date: August 2017 Nashua, NH
2. Ninety-degree bends of conduit with a diameter larger than 1 inch shall be
made with factory-made elbows. Conduit elbows larger than 2 % inches
shall be long radius. Field-made bends and offsets shall be made with an
approved hickey or conduit-bending machine. Changes in directions of
runs shall be made with symmetrical bends or cast-metal fittings.
3. At connections to sheet metal enclosures and boxes, a sufficient number of
threads shall project through to permit the bushing to be drawn tight
against the end of the conduit, after which the locknut shall be pulled up
sufficiently tight to draw the bushing into firm electrical contact with the
box. Conduit shall be fastened to sheet metal boxes and cabinets with two
locknuts where required by NFPA 70 where insulating bushings are used,
where bushings cannot be brought into firm contact with the box, and
where indicated.
4. Conduit joints shall be made with tapered threads set firmly. Each length
of conduit cut in the field shall be reamed before installation. Where
conduit is threaded in the field, each threaded end shall consist of at least
five full threads. Corrosion-inhibitive compound (cold galvanizing paint)
shall be used on all conduit threads or any locations where the original hot
galvanized surface has been compromised.
5. Conduit stubbed-up through concrete floors for connections to free-
standing equipment except motor-control centers, cubicles, and other such
items of equipment shall be provided with a minimum of a 12” riser above
the floor slab is of sufficient thickness; if not, a floor box shall be provided
and set flush with the finished floor. Conduits installed for future use shall
be terminated with a coupling and plug set flush with the floor.
3.02 SUPPORTING DEVICES
A.
Install supporting devices to fasten electrical components securely and
permanently in accordance with NEC requirements.
Coordinate with the building structural system and with other electrical
installations.
Conform to manufacturer's recommendations for selection and installation of
supports.
Install individual and multiple (trapeze) raceway hangers and riser clamps as
necessary to support raceways. Provide U-bolts, clamps, attachments, and other
hardware necessary for hanger assembly and for securing hanger rods and
conduits.
Support parallel runs of horizontal raceways together on trapeze type hangers.
RACEWAYS, BOXES AND SUPPORTING DEVICES
WOODARD & CURRAN 26 05 34-11
