Siemens 3AH 사용 설명서 - 페이지 25

{카테고리_이름} Siemens 3AH에 대한 사용 설명서을 온라인으로 검색하거나 PDF를 다운로드하세요. Siemens 3AH 38 페이지. Vacuum circuit breaker operator module
Siemens 3AH에 대해서도 마찬가지입니다: 지침, 설치, 작동, 유지보수 (33 페이지), 설치 운영 및 유지보수 (20 페이지)

페이지 인쇄

1. Table of Contents

Maintenance

Electrical Close and Trip Check ( Control Power Required)

A check of the circuit breaker control circu its shall be

performed . This check is made with the circuit breaker

energ ized by control power either from the switchgear or an

external control power source.

1. Once the circuit breaker springs are charged, move the

switchgear Close/Trip switch to the Close position. Verify

by both the sound of the circuit breaker closing and by

the main contact status indicator that th e circuit breaker

contacts are closed.

2. As soon as the circuit breaker has closed, the automatic

spring charging process is repeated.

3. After a satisfactory close operation is verified, move the

switchgear Close/Tri p switch to the Tri p position. Verify

by both the sound of the circuit breaker o pening and by

the maih contact status indicator that the circuit breaker

contacts are open.

4. After a satisfactory open operation is verified, h old the

circuit breaker manual Trip button and apply and main

tain an electrical close signal. The circuit breaker should

close, immediately trip, the close spring should charge,

and the circuit breaker should not attempt to close.

Completion of these checks demonstrates satisfactory

operation of auxiliary switches, internal relays a n d open a n d

close coils.

Checks of the Spring Charging Motor

No additional checks of the spring charging motor are neces

sary.

Vacuum Interrupters

The l ife expectancy of vacuum interru pters is a function of

the n umber of interruptions a n d magnitude of current inter

17).

rupted (Table 3 and Figure

They must also be replaced before certain amount of

mech a n ical operations (Table 2) or wh en the contacts have

been eroded beyond a l l owed limits. Vacuum interrupter

replacement proce d u res a re detailed in the following main

tenance instructions.

The vacu um interrupter contact l ife curves F

fered as a guide to life expectancy.

Vacuum Integrity Check

( using MechanicaiTest) ( Figure

Before putting the circuit breaker into service, or if a vacuum

interrupter is suspected of leaki n g as a result of mechanica l

damage, check t h e vacu u m either mechan ically as described

in this section or alternatively electrically using a high poten

tial test set as described in the next section.

Open and isolate the circuit breaker and detach the insulat

ing coupler (48) from lever (48.6) (Figure

The atmospheric pressure will force the moving contact of a

hermetically sealed vacu u m interrupter into the " Closed" po

sition, causing lever (48.6) to move into the position shown

18.

in Figure

(88)

a re of

18)

18).

A vacuum interrupter may be assumed to be intact if it

shows the following cha racteristics:

An appreciable closing force has to be overcome when lever

(48. 6) is moved to the "Open" position by h a n d ( Figure

When th e lever is released, it must automatically return to

the "Closed" position with an audible soun d as the contacts

touch.

After checking the vacuum, reconnect the lever (48.6) to the

insulati ng coupler (48) ( Figure

High-Potentia l Tests

The next series of tests (Vacuum Integrity Test a n d Insulation

Tests) involve use of high voltage test equipment. The circuit

breaker u n der test should be inside a suitable test barrier

equipped with warning lights.

Vacuum Integrity Check ( using Dielectric Test)

A high potentia l test is used to verify the vacuum integrity

of the circuit breaker. The test is conducted on the circ u it

breaker with its primary contacts in the Open position.

Hazardous voltages used in high potential

tests.

Will cause severe personal injury and death.

Follow safe procedures, exclude u n n ecessary

personnel and use safety barriers. Keep away

from the circuit breaker during application of

test voltages.

Disconnect the plug j u m per from between the

circuit breaker and switch gear before conduct-

ing high pote ntial tests.

After test completion, grou nd both ends and

the middle portion of the vac u u m i nterrupter

to dissipate any static charges.

Vacuum interrupters may emit X-ray radiation.

Can cause personal injury.

Keep personnel more tha n six (6) feet away fro

a circuit breaker under test.

High Potential Test Voltages

The voltages for h i g h potential tests are shown in Table 4.

Table 4. High PotentiaiTest Voltages

Max AC rms

Equipment kV

Rating

1 4kV

4.76kV

8.25kV

27kV

1 5kV

27kV

38kV

60kV

18).

A DANGER

WARNING

Max DC Avg

20kV

38kV

85kV