Answer Posted / rajan singh tanwar

This is based on
very simple
concept:-
It has three
letters and they
are coded as
follows:-

First Letter -
Operation
Quantity
A - Phase angle
comparison
B - Balanced Current
C - Current (Amps)
D - Differential
E - Direction
F - Frequency
K - Rate of rise of
current
M - Manual
O - Oil Pressure
P - Poly phase VA
R - Reactive VA
S - Slip Frequency
T - Temperature
V - Potential
W - Watts
X - Reactance
Y - Admittance
(Conductance)
Z - Impedance

Second Letter -
Measurement
A - Attracted
armature
B - Buchholz
C - Induction
D - Induction Disc
G - Galvanometer
I - Transmitter
J - Mixed Types
M - Magnet
(polarized)
P - Plug
R - Rectifier
S - Synchronized
Motor
T - Transistor
W - Weight (Gravity)

Third Letter -
Application
A - Auxiliary
B - Testing
C - Carrier or
Counting
D - Directional
E - Earth/Ground
F - Plug or Alarm
Indicator
G - General or
Generator
H - Harmonic
Restricted
J - Tripping
JE - Tripping
(Electrical
Reset)
JM - Tripping
(Manual
Reset)
JS - Tripping (Self)
JC - Tripping
(Conductor)
K - Check Alarm
L - Local Limiting
M - Same Phi or
motor
N - Negative
Sequence
O - Out of Step
P - Potential
Failure
R - Re-closing
S - Synchronizing
T - Timer or
Transformer
U - Definite Time
V - Voltage
Resistant
W - Piolet Wire
WA - Interposing
WS - Inter-tripping
X - Supervisory
Y - Flash Back
(Black
Fire)
Z - Special
Application
Z0 - Zero Sequence

Examples :
CDG - Current
(operation
), Disc
(Measurement),
General Purpose(
Application)
CAG - Current
(operation
), Attracted
armature(
Measurement),
General
Purpose(Application)
VAJ - Potential
(operation
), Attracted
armature(
Measurement),
Tripping(
Application)
VTT - Potential
(operation
), Transmitter(
Measurement),
Transformer
(Application)
VAZ - Potential (
operation),
Attracted
armature
(Measurement),
Special Application
VAA - Potential (
operation),
Attracted
armature
(Measurement),
Auxiliary
(Application)

Thanks I hope it
will help you.
Rajan Singh Tanwar
J.K.Cement Ltd.

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