pamphlet on neutral section maintenance-eng
DESCRIPTION
Railway short Neutral section maintaTRANSCRIPT
Neutral Sections are provided to isolate different phases of power supply in adjoining OHE fed by
adjacent substations, which are normally connected to different phases of supply.
Short Neutral Section Assembly PTFE Type.
• Short neutral section is light weight contact wire insulator of composite type (Resin bonded glass fiber core protected with wear resistance ceramic beads) with Poly Tetra Fluro Ethylene, known as PTFE as shown in figure 1. These should be as per RDSO,s drg. No.
(i) ETI/OHE/SK/551- Arrangement of neutral section for conversion with short neutral section.
(ii) ETI/OHE/SK/552- Arrangement of short neutral section at existing feeding post.
• Speed of trains under such neutral section assembly is 200 kmph.
• This assembly has advantages of ease of installation even on flat curved locations and substantially reduced maintenance.
• The lengths of PTFE type neutral sections are 9.0 m, 5.0 m and 3.736 m.
Locations
NS
400 m 200 m
i. PTFE type short neutral section is erected on level tangent track, flat curves and difficult locations.
ii. The stagger of short neutral section is zero at support.
iii. The PTFE type short neutral section is located on track at a distance of at least 400 meter, after the stop signal and 200 meter before the stop signal as shown in figure below.
Maintenance
1 a. Check any cracks on anti- torsion tube to messenger clamp.
b. Check free movement of telescopic anti-torsion tube.
2 a. Check earthing lug for any flash mark and loose connections etc.
b. Ensure that earth wire is provided with lug.
3. a. Check ceramic beads for any crack.
b. Clean carbon deposits under ceramic beads by wiping with cotton cloth soaked in petrol.
4. Check clearances between:
a. Arcing horn and arc catcher (horizontal clearance maximum 320mm).
b. Arc catcher and ceramic bead (vertical clearance minimum 170mm).
5. Check burning of arc traps and arcing horns.
6. Check complete bracket of PTFE for any abnormality.
7. Check flash marks on structure bond connected between PTFE mast and rail.
8. Measure earth resistance twice in a year, it should be less than 10 Ohms.
2968 NOMINAL LENGTH OF INSULATING SECTION
3736 NOMINAL LENGTH OF CONTACT WIRE TO BE REMOVED
384768 INSULATOR CREEPAGE
LENGTH 1100384
1 CERAMIC BEAD INSULATOR
CONTACT WIRE CLAMPCONTACT WIRE
NORMAL DIRECTION OF TRAVEL
ANTI-TORSION 9SPRING DROPPER
12 ADJUSTABLE 'V' DROPPERS FOR LEVELLING OF ARC CATCHER
4 2 B
X
CABLE TIE
2 CONTACT WIRESPLICE
660660
100 OFFSET
11 JUMPER AT EARTH
POTENTIAL
14 SWIVEL CLIP
13 SWIVEL CLAMP
10 ARC CATCHER
ANTI-TORSION TUBE TO
MESSANGER CLAMP 8
THIS DIMENSION INDICATES SEPARATION BETWEEN
EDGES OF CLIPS
4 MESSANGER/ JUMPER CLAMP
EARTHED SUPPORT AND REGISTRATION POINT
CONNECT TO EARTHING
SYSTEM WITH COMPRESSION
LUG
G.F. MESSANGER INSULATION 6
MESSENGER STRAND 19/2.1 HARD DRAWN COPPER CADMIUM
1100
735 535
2500
340
50 50
340
900
2300
7 MESSANGER/ END
CLAMP
170 mmMax. 320mm
Safety Tips
�Ensure that power supply of elementary section of both ends of neutral section is switched off and earthed before commencing the work.
�Only after obtaining permit to work (PTW) from TPC, climb on roof of tower wagon.
� Always use industrial helmet during work at site.
Disclaimer:
It is clarified that this pamphlet does not supersede any existing provisions laid down by RDSO, Railway Board or Zonal Railways. The pamphlet is for guidance only and it is not a statutory document.
If you have any suggestion or comment, please write to:Director (Electrical), CAMTECH, Maharajpur,
Gwalior (M.P.) – 474 005Ph.0751-2470740, Fax 0751-2470841
(For Official Use Only)
Hkkjr ljdkj GOVERNMENT OF INDIA
jsyjsyjsyjsy ea=ea=ea=ea=kykykyky;;;; MINISTRY OF RAILWAYS
PAMPHLET
on NEUTRAL SECTION MAINTENANCE
PTFE TYPE
egkjktiqj Xokfy;j &&&& 474 005Maharajpur, GWALIOR - 474 005
CAMTECH/E/2010-11/Pamp-NSMAY 2010