Show and Tel

Show and Tel

By Laurence Stewart

​Conduit is a type of containment system commonly used in the electrical trade.

It can can be used both in and outdoor.

It is versatile and comes with various accessories that are relatively easy to install.

Some of the most common accessories are shown next.

​Conduit

​Power is a measure of the rate of energy transfer in relation to the the voltage and current in a circuit. It is measured in Watts(W)

​​Power

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​Voltage is the pressure from a power source in an electrical circuit that pushes charged electrons through a conducting loop. Measured in volts(V)

​​Voltage

​

The stream of charged electrons moving through a conductor. Relative to voltage(V) and impedance(Z).

Measured in amps.​

​​Current

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Multiple Choice

If we know the Power(W) of a piece of electrical equipment and supply voltage(V) we can work out the current(I) using the equation?

• I = P x V

• I = P/ V

• V = I x P

• I = V² / P

​Allows for an inspection point. Can also be used as aa feeding point for longer cable runs.

​Through Box

​Used to end a conduit run. Accessories or lid can be fitted directly to box using M4 screws.

End ​Box

​Allows for connection of conduit to various accessories/boxes. Available in male and female depending on application.

Adaptor​​

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​Can be used for intersections at 90⁰ when required. Lid required to ensure integrity.

​T Box

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Multiple Choice

What type of conduit accessory allows for intersections at 90 degrees?

• Adaptor

• T box

• End box

• Through box

Multiple Choice

What type of accessory allows for connection of conduit to various accessories?

• Adaptor

• Through box

• End box

• T Box

Types of Cable

The range of cable types available is extensive depending on there application​, some of the most common used as a domestic electrician can be seen on the next slide.

​Common Cable types in domestic installations

​Most common form of cable used in domestic installation.

Benefits include:

Good Mechanical protection

Easy to install/terminate

Range of sizes for different applications.​

​​PVC/PVC

​

​This type of cable is used for communcation purposes.

It has a high data transfer rate

100Mbps +.

Shielding and twisted pairs offer protection from electrical interference.​

Cat 5e​

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​Armoured is used when additional mechanical protection is required.

Special glands must be used for termination to ensure armour is earthed.

Range of sizes available.​

​​Steel wire Armoured

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Multiple Choice

What type of cable would be best suited for supplying an outside shed via a trench?

• PVC/PVC

• Cat 5e

• Steel wire armoured

• PVC singles