Answer / ajay

megger is used to measure insulation resistance.multimeter is used to measure coil resistance

Answer / raghavendran

The working mechanism of a Meggar and a Multimeter with
regard to measuring a resistance is the same.In this case
Voltage is applied across the body whose resistance is to be
measured.
1)for meggar, there will be two coils namely 'control coil'
and 'deflection coil'.The 'Control Coil' will always be kept
energized by the DC Source.If the insulation strength is low
then there will be current flow through the 'deflection
coil' and the resulting torque in the coil will produce
deviation in the pointer connected to a permanent magnet.The
torque produced by the two coils will be opposite in nature.
2)for multimeter,the control coil will be replaced by a
spring whose tension tends to keep the pointer in one
direction.when current flows through the deflecting coil (ie
when weak insulation)a torque, opposite to the tension of
the spring is produced tending to move the pointer in other
direction.thus showing the corresponding Ohmic Value.

Answer / pillay

meggar is actually a brand name, but it is more often than
not associated with with insulation resistance testers.The
meggar tester /or insulation tester actually uses a high
voltage at its terminals to do the measurements thus being
more efficient in driving In a current and than the
measurements are made.
Multimeter as the name says is used for a variety of
measurements but using basically the same moving coil.when a
high resistance or very small leakage is to be tested using
a multimeter it usually fails because of its in ability to
drive a current through a very high resistance circuit and
give a correct reading.
I would always use a MEGGAR tester for insulation testing
and a multimeter for other testing.

Why we use a shunt capacitor or synchronizing Motor To Improve a Power factor pls reply me in this mail dinesh_elect_eng@yahoo.com

4 Answers  

---

how u calculate ups battery backup

2 Answers  

---

what are the values of VRY,VYB,VBR,Vry,Vyb,Vbr,Vrn,Vyn,Vbn for Magenetic balance test of 100 KVA and 63 KVA Distribution transformer

0 Answers  

---

what is the advantage of connecting capacitors in delta than in star?

1 Answers   NTPC,

---

For a load of 40HP induction motor.what will be size of Armoured copper cable require to connect the motor to starter in Star-Delta?

1 Answers   CG,

---

What is d role of reactive power in power system??How it produce & consume?

5 Answers   ABB,

---

If a rotary UPS is in line through grid power; What would be the impact on Power Factor if the load through rotary ups is 25% , 50% , 75% & 100%. Will the power factor reduce with less load?

0 Answers  

---

Resistance of a conductor in a close electrical ckt is practically zero why?

1 Answers  

---

What is the size of cable to be used for a Space Heater in UPS 160KVA of carrying 10 Amps current with 240 V ,1 Phase?

3 Answers  

---

if v r considering a 4000/1A ct,if v inject 1 amps in secondary core wat happens?(consider as 2 core ct,each for metering and protection)

1 Answers  

---

how to calculate the neautral earthing conductor size for a 500kva dg set.

2 Answers  

---

Why we check only first column of root locus..?

1 Answers   IES,

---