This document provides information about an electrical installation and maintenance course for the second quarter. It discusses reading measurements in terms of current using Ohm's Law, induction clamps, and voltmeters. Ohm's Law expresses the relationship between current, voltage, and resistance using the equation R=V/I. Methods for reading electrical current include using Ohm's Law equations and reading measurements on ammeters, which measure current in amperes. Small hand scales measure from 0 to 1 ampere in 0.2mA graduations while long hand scales measure from 0 to 15 amperes in 1 ampere graduations.

1. ELECTRICAL
INSTALLATION &
MAINTENANCE
QUARTER 2: WEEK1

2. SCHOOL CALENDAR
January
4 Start of Second Quarter
30
Examination Week (G11 &
G12)
February
3
6 to 10
Midyear Break &
Compliance Week

3. BLENDED
- MODULAR
- FACE TO FACE

4. LEARNING OBJECTIVES
 Read measurement in terms of current using Ohm’s Law, induction (clamp
tester) and volt-ohmmeter

5. Reading Measurements in terms of
Current
 Electrical Current represented by I is the normal flow of current in an
electric circuit. It is the rate of flow of electric charge. No current can flow if
the circuit is broken.
 The unit of measurement for current (I) is ampere. It was named after a
famous experimenter in electricity, Andre M. Ampere, a Frenchman.
 Ohm’s Law expresses the relationship of current, voltage, and resistance, as
described in an equation, R = V/I, where resistance is the quotient of the
voltage (V) over the current (I).

6. Where:
Quantity Symbol Unit of
Measurement
Unit
Current I Ampere (“Amp”) A
Voltage V Volt V
Resistance R Ohm Ω

7. Methods of
Reading Electrical
Current
A. Ohm’s Law
Equation: E = I x R –
equation in terms of voltage (E)
I = E / R –
equation in terms of current (I)
R = E / I –
equation in terms of resistance (R)

8. TRY TO ANSWER

13. Ammeter Reading
 Abstraction: From reading measurements in
amperes, reading measurements varies on
type and the capacity of measuring tools to
be used. The sample illustrations range only
at 15amperes;
 Small hand scale - 0 to 1 ampere counted
0.2mA per graduation
 Like the small illustration on the left side,
reading starts at 0 to first graduation with
0.2mA, next counted as 0.4Ma, next to
0.6mA and so on….to reach long hand scale
ranging as 1amp. The same procedure is
used to count up to 2amp, next to 3amp, and
so on.
 Long hand scale- 0 to 15amperes counted as
1ampere per graduation

15. TRY THIS!!!

19. END