Directional dust deposit gauge
measurements( DDDG)
The dust gauges are described in the IEC
Publication No. 60815 and measure the amount
of contamination that may deposit on an
insulator in the vicinity on a monthly basis Both
the soluble (conductive) and non-soluble (nonconductive) components can be recorded. As
defined in the IEC document, from these values,
the Pollution Index and international pollution
severity classification can be established.
Directional dust deposit gauge
( DDDG)DESCRIPTION
the gauge consists of four vertical tubes each
with a slot milled in the side, these being so
arranged as to face north, south, east and west.
A removable container which collects the
deposits blown into the slots, is attached to
each tube.
Directional dust deposit gauge
DESCRIPTION
Directional dust deposit gauge
DESCRIPTION
Directional dust deposit gauge
DESCRIPTION
These containers are removed at monthly
intervals, their contents mixed with 500ml of
demineralized water and the conductivities of
the solutions measured. The Pollution Index is
defined as the average of the conductivities of
the four directions, expressed in μS/cm and
normalized to a 30 day interval.
The advantage of this technique
The advantage of this technique is its simplicity
and the fact that it can be used at an
unenergized site without insulators or facilities
other than those required for the mounting of
the gauges.
Benefits of using
Determines the level of contamination
 Determines practical insulator washing
periods.
 Helps to determine the creepage distance,
choose the insulator type and insulator
dimensions for design the new over head
line.
Directional dust deposit gauge
pollution index in relation to SPS class
Directional dust deposit gauge pollution index in
relation to SPS class
Average monthly
value
over one year
< 25
Site pollution severity class
a
very light
25 to 75
b
light
76 to 200
c
medium
201 to 350
d
high
> 350
e
very high
Solution Conductivity (µS/cm)
AL ZOUR AREA
Direction
Solution
Solution
Corrected
Pollution Pollution
Volume Conductivity Conductivity
Index
level
(ml)
(µS/cm)
(µS/cm)
North
500
437
437.000
South
500
429
429.000
377
East
500
322
322.000
West
500
320
320.000
very
heavy
Solution Conductivity (µS/cm) AL
SHUIBA AREA
Direction
Solution
Solution
Corrected
Pollution
Volume Conductivity Conductivity
Index
(ml)
(µS/cm)
(µS/cm)
North
500
149
149.000
South
500
120
120.000
141
East
500
104
104.000
West
500
192
192.000
Pollution
level
medium
Directional dust deposit gauge
pollution index in relation to SPS class
Directional dust deposit gauge pollution index in
relation to SPS class
Average monthly
value
over one year
< 25
Site pollution severity class
a
very light
25 to 75
b
light
76 to 200
c
medium
201 to 350
d
high
> 350
e
very high
Solution Conductivity (µS/cm)
AL ZOUR AREA
Solution Conductivity (µS/cm)
AL SHUIBA AREA
AL ZOUR AREA CONTAMINATION
RECOMANDATION
• Installation a number of these devices in all
areas of the network to determine the
percentage of pollution in different areas