Clamp-on Meter & Megger – Testing Tools in
Electrical Engineering
Department: Electrical Engineering (EEE)
Course: Basic Electrical Measurement / Electrical Machines / Lab Instruments
Semester: 3rd / 4th (Diploma or B.Tech)
Prepared for: BVM Engineering College, Anand
GTU Subject Code: 3320901
Document Overview: -
This document provides detailed notes on two important electrical testing tools,
like Clamp-on Meter and the Megger. It includes:
• Working principles and internal construction
• Types of clamp meters (CT, Hall effect, flexible)
• Applications in industrial and field testing
• Insulation resistance testing using Megger
• Safety tips and practical conclusions
• Ideal for lab preparation, viva, and university exams
Use Case: GTU Practical Notebook | Viva Prep | Electrical Lab Record
, Understanding of Clamp-on meters and Meggers
1. CLAMP ON METER: -
• It is an electrical test tool that combines a basic digital multimeter with a
current sensor. Clamps measure current, while probes measure voltage. A
hinged jaw integrated into an electrical meter allows technicians to clamp the
jaws around a wire, cable, or other conductor at any point in an electrical
system and measure current in that circuit without disconnecting or de-
energizing it.
• Inside the plastic moldings, the hard jaws are made of ferrite iron and designed
to detect, concentrate, and measure the magnetic field generated by current
flowing through a conductor.
• Clamp meters are ideal for measuring high current levels. DMMs cannot
measure 10 A of current for more than 30 seconds without risking damage to
the meter.
• Consider summarizing as: “Most clamp meters can measure from 0 A to 600 A,
while advanced models and iFlex®
accessories can handle up to 2500 A.
• Clamp meters are used on industrial
equipment, industrial controls,
residential/commercial/industrial
electrical systems, and
commercial/industrial HVAC.
➢ There are three types of clamp meters:
1. Current transformer clamp meters:
measure only alternating current (AC).
Electrical Engineering
Department: Electrical Engineering (EEE)
Course: Basic Electrical Measurement / Electrical Machines / Lab Instruments
Semester: 3rd / 4th (Diploma or B.Tech)
Prepared for: BVM Engineering College, Anand
GTU Subject Code: 3320901
Document Overview: -
This document provides detailed notes on two important electrical testing tools,
like Clamp-on Meter and the Megger. It includes:
• Working principles and internal construction
• Types of clamp meters (CT, Hall effect, flexible)
• Applications in industrial and field testing
• Insulation resistance testing using Megger
• Safety tips and practical conclusions
• Ideal for lab preparation, viva, and university exams
Use Case: GTU Practical Notebook | Viva Prep | Electrical Lab Record
, Understanding of Clamp-on meters and Meggers
1. CLAMP ON METER: -
• It is an electrical test tool that combines a basic digital multimeter with a
current sensor. Clamps measure current, while probes measure voltage. A
hinged jaw integrated into an electrical meter allows technicians to clamp the
jaws around a wire, cable, or other conductor at any point in an electrical
system and measure current in that circuit without disconnecting or de-
energizing it.
• Inside the plastic moldings, the hard jaws are made of ferrite iron and designed
to detect, concentrate, and measure the magnetic field generated by current
flowing through a conductor.
• Clamp meters are ideal for measuring high current levels. DMMs cannot
measure 10 A of current for more than 30 seconds without risking damage to
the meter.
• Consider summarizing as: “Most clamp meters can measure from 0 A to 600 A,
while advanced models and iFlex®
accessories can handle up to 2500 A.
• Clamp meters are used on industrial
equipment, industrial controls,
residential/commercial/industrial
electrical systems, and
commercial/industrial HVAC.
➢ There are three types of clamp meters:
1. Current transformer clamp meters:
measure only alternating current (AC).
