The document discusses megger testing devices used to test insulation levels of electrical systems. It describes the different types of meggers, including electronic and manual types, and explains their construction and working principles. The document notes that meggers are used to determine insulation levels and leakage current, and to minimize errors when testing electrical systems whose insulation decreases over time.

1. Made By – Shubhankar Das
Collage – NIMAS
Department – B.H.H.A
Sem – 3rd
Roll No – 21584921003
Subject – Hotel Maintenance

2. Following contents will discussed:
❑ What is megger.
❑ Why use megger & usesof megger.
❑ Types of megger.
❑ Construction of megger.
❑ Working principle of megger.

3.  Megger is a measuring device
 Megger is expert in ground earth testing
 It gives high accuracy
 Megger tester are easy to use and having
lightweight

4.  Insulation of any electrical system decreased
 To minimize the error we use megger
 To determine the leakage current
 It is used for verifying the insulation level

5.  Electronic Type (Battery Operated)
 Manual Type(Hand Operated)

6.  Digital Display
 Wire Leads
 Selection Switches
 Indicators
 Advantage
 Disadvantage

7.  Analog Display
 Hand Crank
 Wire Leads
 Advantages
 Disadvantages

9.  Voltage for testing produced by hand operated
megger by rotation of crank in case of hand
operated type , a battery is used for electronic
tester.
 500 volt DC is sufficient for perfoming test on
equipment range up to 440 volts.
 1000 v to 5000 v is used for testing for high
voltage electrical system.
 In hand operated megger electromagnetic
induction effect is used to produce the test
voltage i.e armature arranges to move in
permanent magnetic field or vice versa.