Lesson 2
Perform Mensuration and Calculations
LEARNING OUTCOMES: At the end of this Lesson, you are expected to do the following:
LO 1. select measuring instruments;
LO 2. carry out measurements and calculations; and
LO 3. maintain measuring instruments.
Definition of Terms
Ampere - basic unit of current
Current - the flow of electrons moving in a given direction
Electronic measuring instrument - portable instruments used to measure electrical quantities such as current, voltage, and resistance
Ohmmeter - an electronic instrument used to measure resistance of a component or the entire circuit
Ohmmeter scale - section of the ohmmeter where the value of the resistance is being indicated
Range multiplier - a portion in the ohmmeter where the actual reading is multiplied by the range value
Resistance - the opposition to the flow of electrons
Resistor - an electronic component that is used to offer opposition to current in an electrical circuit
Resistor color coding - a scheme to determine the value of resistors by color bands printed on their bodies as code
Test Probes - connectors connected to terminals of the VOM and component’s terminals or test points in a circuit to be tested. They are oftentimes red and black in color
Tolerance - the fourth color in the 3-band color coding that indicates the percentage of deviation from its color coded value
Volt - basic unit of voltage
Voltage - an electrical pressure that pushes current to flow within a load through a conductor
Zero-ohm adjuster - part of the ohmmeter that is used in adjusting the pointer of the ohmmeter to zero before resistance measurements or continuity tests are made.