background image

              

 

 

Nuova Via di Piano Comprensorio Vulcano 

Sesto San Giovanni, MI 20099 Italy 

Tel. 02-24105.001 

 

IS 2653 GB

 

Page 

16

 of 

18

 

 

Time base 

V

is

u

a

in

s

p

e

c

ti

o

n

 

U

V

 c

a

m

e

ra

 a

n

d

 

in

fr

a

re

d

 

e

x

a

m

in

a

ti

o

n

 

W

e

tt

a

b

il

it

y

 

3 Months 

 

 

1/2 Year 

 

When plant is off 

 

 

Table 3 – Composite insulator intensive maintenance plan 

 
 
 
 
 

10 

General maintenance plan 

 
The general maintenance plan is described in the next 

Table 4

 
 

Component 

Time base 

Description 

Notes 

Composite insulators  See 

Chapter 9

 

Inspection and maintenance 

See 

Chapter 9

 

Gas SF6 

Monthly 

Check the pressure 

Record the data 

Toroids 

When plant is off 

Clean  the  surface  and  check  for 
scratches or deformation. 
Check the fixing bolts to the flanges. 

Anticipate  the  controls  if 
UV 

camera 

reveals 

corona inception.  

Gas 

valves, 

electrical  equipment 
and 

connecting 

cables 

When plant is off 

Clean the cubicle. 
Check for gas leaks. 
Check  functionality  of  pressure 
gauge and DILO Type valves. 
Check terminal blocks, wiring, cables 
and cable glands. 
Check and clean the junction box. 

Check  all  gas  joints  to 
the  DILO  Type valves on 
the bushing. 
Check the cables and the 
cable tray to the bushing. 

Current terminals 

When plant is off 

Check for evidence of hot spots. 
Check  the  terminals  and  tighten  the 
connecting  bolts  to  the  bushing 
flange. 
Check  the  cable  clamps  and  the 
bolting to the terminal. 

Anticipate  the  controls  if 
IR  camera  reveals  hot 
spots. 
Contact 

GE 

Grid 

Solutions  RPV in case of 
evidence  of  hot  spots 
during the inspection. 

Grounding terminals 

When plant is off 

Check for evidence of hot spots. 
Check  the  connection  integrity  and 
the bolt locking. 
Verify  the  effectiveness  of  the 
grounding. 

Contact 

GE 

Grid 

Solutions RPV in case of 
evidence of hot spots. 

Содержание PWHS

Страница 1: ...pany name udated 07 07 2016 AF LP 3 Storage and transport conditions updated 22 08 2016 AF LP IS 2653 GB GE Proprietary Information Class III Confidential Export Controlled U S Government approval is required prior to export from the U S re export from a third country or release to a foreign national wherever located GAS FILLED HV WALL BUSHING PWS PWHS OPERATING AND MAINTENANCE INSTRUCTIONS ...

Страница 2: ...3 3 Storage conditions 6 4 Technical characteristics 6 5 Bushing preparation and installation 7 5 1 Controls at the arrival 7 5 2 Bushing unpacking 8 6 Gas SF6 characteristics and gas filling instruction 10 6 1 Gas first filling operation and control of alarm and tripping signals 11 6 2 Gas refilling during the bushing normal operation 11 7 Gas density monitor 13 8 Power factor taps 14 9 Composite...

Страница 3: ...voltages above 1000V 2 Safety In this document important safety requirements are highlighted by the word CAUTION and important operative instructions are evidenced by the word NOTE This manual must be available to the personnel responsible of the installation operation and maintenance of the bushings The wall bushing is a high voltage AC DC device filled under pressure with SF6 gas that has to be ...

Страница 4: ...personnel involved in wall bushing assembly All problems detected during the bushing installation must be reported to the Foreman and to GE Grid Solutions RPV Supervisor The bushing is a pressurized device Operations on the valves pressure gauges pipes protective devices must be performed by qualified operators with the proper equipment and respecting the instructions of this manual Foreman and op...

Страница 5: ...ent of the crate during the transport it is responsibility of the transport company to carefully fix it on the vehicle by suitable retain systems like ropes synthetic pulling bands or any other method The maximum allowed transport acceleration along the three axis is 3g 29 43 m s2 In case of transport by truck along very bad roads bumpy roads the speed must be adequately reduced to max 30 km h Tru...

Страница 6: ...ned and tested in accordance with the IEC 62199 and IEC 60137 standard Each section is based on A composite insulator with silicone sheds The internal shielding arrangement An internal aluminium tube conductor The top flange with the line terminal The top toroidal electrical shield The two sections joined by the central flange make the complete bushing The sealing joints between the parts are desi...

Страница 7: ...t the arrival Before proceeding with the unpacking operation it is necessary to perform the following controls Check the wooden crate status Check the external visual impact recorder s Open the crate and inspect packaging and goods inside see next paragraph 5 2 Check the pressure of the gas inside the bushing that must be 0 11 MPa abs 0 1 bar gauge see Figure 3 Check the composite insulators statu...

Страница 8: ...supports and it is locked by locking belts Additional intermediate belts support the composite insulator to a wooden structure Figure 4 Bushing crate inside view Figure 5 Bushing inside the crate top view The transport box can be lifted by a suitable crane After the opening of the crate the visual inspection of the bushing and the removal of the locking ropes and locking blocks the bushing can be ...

Страница 9: ...low the steps indicated into the provided erection and installation manual IS 2654 GB Figure 7 Example of bushing extraction and lifting CAUTION The two composite insulators are protected by a PE plastic foils Remove the protection only after the installation of the bushing on the wall and just before the energizing CAUTION To lift the bushing do not wrap ropes i e tie lifting method around the si...

Страница 10: ...mium Supplier The minimum requirement is that the characteristics will be in accordance with the data listed in the GE RPV limits column The gas filling must be performed with an equipment that prevents dispersion of the SF6 gas in the atmosphere As an example next Figure 8 shows a gas plant manufactured by the German company DILO GmbH Figure 8 Vacuum filling gas plant DILO and connecting valves N...

Страница 11: ...re up to 0 2 MPa abs 1 bar gauge Pressure must be directly measured on the gas density monitors installed on the bushing flange Check all the gas seals for leakages with a suitable SF6 leak meter device In case of significant leakages stop activities and contact GE Grid Solutions RPV supervisor If the bushing does not show any leakage gradually increase the pressure at the rated filling pressure v...

Страница 12: ... the DILO machine check that the machine set up is for gas filling and that the connecting pipe is full of SF6 In the case of direct filling from the bottle check that the bottle is effectively charged with SF6 that the gas quantity is sufficient for the re filling the pressure reduction unit and the pipe are compatible with the DILO filling system and all equipment is specific for SF6 filling app...

Страница 13: ...cation on the scale is expressed in MPa absolute referred to a gas temperature of 20 C This means that the instrument converts the gas density into a value of pressure referred to 20 C independently for the effective temperature of the gas The instrument reading practically does not change with the gas temperature that is a function of the bushing loading condition and ambient temperature Changing...

Страница 14: ...epair procedure is described into the component manual see reference in the summary prepared for the specific wall bushing The composite manufacturer can provide a repairing kit and also a technical support for the repairing activity Useful indications about the composite insulator maintenance plan main actions are shown in Table 2 CAUTION Severe electrical shock risks deriving by the fact that th...

Страница 15: ... the camera must be properly set in order to avoid false signals and background noise In addition an infrared scan on the line terminal and the incoming cables can reveal incipient hot spots phenomenon that can evolve into a serious damage on the electrical connection and then of the bushing itself In case of significant variation of the UV and IR emission plan the following actions UV emission Im...

Страница 16: ... Gas valves electrical equipment and connecting cables When plant is off Clean the cubicle Check for gas leaks Check functionality of pressure gauge and DILO Type valves Check terminal blocks wiring cables and cable glands Check and clean the junction box Check all gas joints to the DILO Type valves on the bushing Check the cables and the cable tray to the bushing Current terminals When plant is o...

Страница 17: ...pect the closure cap and the fixing screws CAUTION Do not remove the closure cap and do not touch the disk when the bushing is filled with gas An explosion of the disk could be very dangerous Gas density monitor 5 years Check calibration and operation of micro switches Check the effective and correct operation of the alarms tripping signal chain from the instruments to the substation systems Bushi...

Страница 18: ...electric terminals Copper silvered Dismount and recycle Toroids Aluminium Dismount and recycle Internal electrostatic shields Aluminium Dismount and recycle Transport supports Aluminium Recycle the aluminium Teflon Dispose or thermo destruction Composite insulators with flanges Fibreglass Dispose or thermo destruction Silicone Dispose or thermo destruction Aluminium Dismount and recycle Electrical...

Отзывы: