Fill in the blank

The supply into a sub-station is a ___________ supply.

The output from the sub-station is a___________ output

How many wires are used in a Delta connection?

The 3-phase, 4-wire system gives a choice of two voltages. These voltages are what?

Phase to phase voltage is measured between what?

___________ diagrams use boxes to show how different parts of circuits are linked together.

__________ diagrams are used to illustrate the layout of buses in a substation.

Which type of diagram do you see here?

In order for a switch to control a light/load, the switch must be connected in _____________.

Transformers only operate using _________ current

__________________________ is used where one light is to be switched from two different positions

What is the first step in testing ?

Which test is used to make sure that live/phase conductor is connected to the fuses and switches.

The letter (Z) represents what?

What does HID stand for ?

Transformers have _____ moving parts

A transformer operates on __________ current

The basic transformer has the following main parts:

1. Primary winding

2. Secondary winding

3. Core

4.________________

Transformers ___________change the frequency between the primary and the secondary