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ELECTRICAL INSPECTION, DIAGNOSIS, REPAIR
ACCURACY vs PRECISION of MEASUREMENTS
AFCIs ARC FAULT CIRCUIT INTERRUPTERS
ALUMINUM SECs & WIRING
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AMPS & VOLTS DETERMINATION
AMPACITY - the LIMITING FACTOR
APPLIANCE EFFICIENCY RATINGS
BACKUP ELECTRICAL GENERATORS
BOOKSTORE - ELECTRICAL
BUILDING SAFETY HAZARDS GUIDE
Cadet & Encore Heater Recall
CIRCUIT BREAKER FAILURE
CIRCUIT BREAKER SIZE for A/C or HEAT PUMP
Classified CIRCUIT BREAKER WARNING
CORROSION in ELECTRICAL PANELS
CORROSION & MOISTURE SOURCES in PANELS
CUTLER HAMMER PANEL FIRE
DEFINITIONS of ELECTRICAL TERMS
DIRECTORY OF ELECTRICIANS
DMM Digital Multimeter, How to Use
ELECTRIC METERS & METER BASES
ELECTRIC MOTOR DIAGNOSTIC GUIDE
ELECTRIC MOTOR OVERLOAD RESET SWITCH
ELECTRIC PANEL AMPACITY
ELECTRIC PANEL INSPECTION
ELECTRIC PANEL MOISTURE
Electric Power Frequency Table
Electricity Basics - how it works
Electrical Circuit ID, Map & Label
Electrical Circuits, shorts
Electrical Code Basics
Electrical Grounding Basics
ELECTRICAL OUTLET, HOW TO ADD & WIRE
Electrical Splices, how to make
Electrical Tools & Tests
Electrical Wire Stripping Tips
Electrical Wiring Books & Guides
Electrical Wiring in Old Houses
EMF RF FIELD & FREQUENCY DEFINITIONS
ELECTRICAL GROUND SYSTEM INSPECTION
ENERGY SAVINGS in buildings
FEDERAL PACIFIC FPE HAZARDS
FIRE SAFETY Checklist, CPSC
GFCI PROTECTION,Testing GFCIs AFCIs
HEATING COST FUEL & BTU Cost Table
HEAT TAPE USAGE GUIDE
Hertz - Definitions of KHz MHz GHz THz
KNOB & TUBE WIRING
LIGHTING, EXTERIOR GUIDE
LIGHTING, INTERIOR GUIDE
LIGHTNING PROTECTION SYSTEMS
LOW VOLTAGE BUILDING WIRING
LOW VOLTAGE TRANSFORMER TEST
MAIN DISCONNECT AMPACITY
MOISTURE SOURCES in PANELS
MURRAY SIEMENS Recall
PHOTOVOLTAIC POWER SYSTEMS
PUSHMATIC - BULLDOG PANELS
REMOTE ELECTRIC POWER, PHOTOVOLTAIC
RUST in ELECTRICAL PANELS
SAFETY for ELECTRICAL INSPECTORS
SE CABLE SIZES vs AMPS
SIEMENS MURRAY Recall
UNDERGROUND SERVICE LATERALS
VOLTS / AMPS MEASUREMENT EQUIP
ZINSCO / SYLVANIA HAZARDS
Electrical conduit: This article answers basic questions about installing electrical conduit. Electrical conduit is metal or plastic rigid or flexible tubing used to route electrical wires in a building.
Page top photo courtesy of Tim Hemm.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Electrical conduit for wiring has some advantages in protecting wires and also in running multiple wires to a location.
The proper selection of electrical conduit materials, fittings, and installation are important for safe electrical wiring. Readers of this article should also see Electrical Code Basics and SAFETY for ELECTRICAL INSPECTORS. This website provides information about a variety of electrical hazards in buildings, with articles focused on the inspection, detection, and reporting of electrical hazards and on proper electrical repair methods for unsafe electrical conditions. Critique and content suggestions are invited.
Cutting, Bending and Threading Electrical Conduit
A Photo Guide to Types of Electrical Conduit
Thin-wall metal conduit
Rigid threaded conduit[photos needed]
Plastic conduit - PVC Tubing
Flexible metal conduit
What's the Difference between Flexible Metal Electrical Conduit and Armored Cable or "BX" Wiring?
Pre-wired flexible electrical conduit whips
For special applications such as shown in our sketch (below left), flexible conduit is often used for convenience or to avoid vibration problems, but steps must be taken to prevent water from entering the conduit and/or special water-resistant wiring and fittings are required. In nearly all new installations the electrician uses a pre-wired liquid tight electrical conduit whip (photo at below right).
Pre-wired whips in residential applications (photo above right) are found connecting air conditioner & heat pump compressor units to their outside power source. There the flexible whip avoids problems with vibration-loosened connections in the conduit. Electrical whips are also used for connecting spas and swimming pool equipment. Shown is a six-foot 3-wire Carlton Carflex™ whip assembly produced by Thomas & Betts. 
Flexible Plastic Conduit - Electrical Nonmetallic Tubing or ENT
What tools you need and the procedures for using conduit?
Tools for Cutting Electrical Conduit
Thin-wall conduit can be cut with a special electrical conduit cutter. To use the cutter, clamp it around the conduit. To cut the conduit, tighten the knurled nut in the handle.
As you tighten, force the cutter around the conduit. The sharp cutting blade cuts a groove that deepens with each revolution, making a smooth, quick cut. After cutting through the conduit, file off any burrs around the edge of the cut.
Tools for Bending Electrical Conduit
Thin-wall electrical conduit can be readily bent by using a special tool designed to make a smooth, even bend with little effort.
The more bends in a run of conduit, the more it is to “fish” the wires through. Plan the conduit run carefully to avoid sharp bends and to make as few bends as possible. Never have more than four right angle bends between openings. Follow the manufacturer’s instructions for the type of conduit bender you use.
How an electrical conduit bender works
How to thread electrical wires through conduit
A fish tape is a thin, flexible metal tape with a hook on one end. The tape is usually packaged on some type of reel. The tape is used to pull wires through conduit or through openings in walls. For conduit use, the tape is inserted in one conduit opening and worked through to the next opening. The wires to be drawn through the conduit are bent around the hook on the fish tape.
If the run is long and has a few bends it is a good idea to wrap some electrical tape around the wires to hold them on the hook. The tape is then reeled in to draw the wires through the conduit. A slow, steady is less likely to kink the tape or jam the wires than is a series of sharp.
Electrical codes allow multiple electrical wires to be pulled through a single conduit, but limit the number of wires allowed in a conduit run depending on the number of wires and the wire diameter or gauge.
The more wires you pull, the more crowded the conduit, so buy larger conduit---perhaps 3/4 inch instead of 1/2 inch.
If our inspection is limited to an external, visual inspection of electrical conduit, we may not immediately be able to see safety and electrical code violations such as use of improper wire type or too many wires in a conduit, but here are some easy to spot concerns that merit further review by an expert:
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