ABB OVB-SDB, Инструкция по эксплуатации

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3.0 BREAKER POLE
3.1 General
The 12/15 kV Outdoor Circuit Breaker type OVB-SDB is developed using well-proven
vacuum interrupters. Excellent arc quenching and insulating properties of vacuum offer
long reliable service.
The construction of the pole of this breaker is very simple and has very less number of
moving parts, so the operating energy level is very low, thus it requires practically no
maintenance. The pole assembly is an independent assembly. Before you start
dismantling the pole ensure that the breaker is isolated from the system and auxiliary
supply. Also ensure that the breaker is in open condition and spring is in discharge
condition.
3.1 Dismantling
1. Three poles of the breaker are mounted on the cross member called duct (Fig.
2, page no. 51). Remove the cover of the duct and disconnect the pole-operating
pin.
2. Remove the nut bolts, which connect pole assembly and duct.
3. Lift the pole from the duct keep it in a clean and dust free area.
4. Check the dimension "A" and record it (Refer Fig 4, page no. 53). Note that the
complete pole shall be dismantled and assembled in a clean and dust free area.
5. Remove the hardware, which connects the top insulator, lower terminal plate and
bottom insulator; take out the support insulator 10002 from the pole assembly.
Take care of rubber bellow during dismantling; avoid any kind of damage to rubber
bellow.
6. Remove the top machined-cover 10007 and bolt 10015 (which holds the vacuum
interrupter) from top terminal plate 10009.
7. Remove the top terminal plate 10009 and take away the top insulator 10001 from
the assembly.
8. Hold the vacuum interrupter 10204 in a firm position with reference to one side of
the lower terminal plate 10010 and remove the operating stud 10100 from the
other side by using proper spanner.
9. Remove vacuum interrupter from the current collector hub 10018 of the lower
terminal assembly. In case of flexible connection as shown in fig. 4c remove the
hardware, which binds flexible connection (10207) with lower terminal plate.
Detach the current collector (10208) from stem of the vacuum interrupter.
10. Check each and every component of the assembly for damage and wear.
11. Check the vacuum interrupter for its correctness. The correctness of vacuum
interrupter can be checked for its vacuum level by following method. Hold the
vacuum interrupter firmly and pull out the moving contact will pull back to its
original position. This means the vacuum level is good.