20
Instruction Book
IB02707112E
August 2015
50/75VCPW-VSR
Breaker To Vacuum Starter Replacement Unit
EATON CORPORATION www.eaton.com
SECTION 6: REPLACEMENT OF
COMPONENTS
6.1 REPLACEMENT OF VACUUM INTERRUPTERS
If the vacuum interrupters fail the vacuum integrity or wear check, or
if they have more than 300,000 operations, they must be replaced.
The three interrupters must be replaced as a set.
WARNING
THERE ARE BELLOWS IN EACH INTERRUPTER THAT SEAL THE MOVING
CONTACT FROM THE ATMOSPHERE. THESE BELLOWS ARE FRAGILE
AND MUST BE PROTECTED FROM ANY TORSIONAL LOADING. AN
APPROPRIATE TOOL MUST SUPPORT THE MACHINED FLATS ON EACH
END OF THE INTERRUPTER WHEN TIGHTENING ANY HARDWARE ON
THE INTERRUPTER. BOTTLE WRENCH, CUTLER-HAMMER PART NUMBER
4A36081H01, IS PROVIDED WITH EACH SET OF REPLACEMENT VACUUM
INTERRUPTERS AND SHOULD BE USED IN THIS APPLICATION.
Remove each vacuum interrupter using the steps listed below:
1. Loosen locknut securing threaded rod to top of standoff insulator
(Figure 6.1). Note the number of threads between the two 10mm
nuts.
2. Rotate insulator clockwise to screw insulator off threaded rod.
3. Remove clamp securing lower end of the vacuum interrupter to
the housing (Figure 6.2).
4. Remove bolt and shunt supports securing end of the lower
terminal to the housing (Figure 6.3).
5. Remove the bolt securing the vacuum interrupter to the upper
terminal (Figure 6.4).
6. Hold insulator down and rotate lower portion of the vacuum
interrupter assembly forward to remove (Figure 6.5).
7. Insert new the vacuum interrupter assembly (reverse of step 6).
8. Install the bolt securing the vacuum interrupter to the upper
terminal, do not tighten.
9. Install bolt and shunt supports securing lower terminal to housing
(Figure 6.6). When tightening insure laminated shunt is straight and
shunt supports are in the correct position.
10. Tighten bolt securing vacuum interrupter to upper terminal while
holding bottle wrench on upper vacuum interrupter stem. Torque to
200 lb-in (22.6 Nm). Insure the laminated shunt is not twisted.
11. Install clamp securing lower end of vacuum interrupter to
housing.
12. Rotate insulator counter-clockwise until the number of threads
noted in step 1 is obtained.
6.1.1 ADJUSTING VACUUM INTERRUPTERS
After 3 new vacuum interrupter’s have been installed, set the proper
open gap using the steps listed below. Three battery operated test
lights or continuity testers are needed for the proper setting of the
open gap.
1. Attach test lights across the upper and lower terminals of each
interrupter.
2. Rotate insulator on middle phase bottle until light flickers. Rotate
clockwise if light is not on, counterclockwise if light is on.
3. From the point the light flickers, rotate insulator on middle phase
bottle counter-clockwise three and twothirds turns to establish
a 5.5mm open gap. Use markings on insulator to verify correct
rotation. (Two thirds turn is equal to 8 divisions that are molded on
the surface of the insulator.)
4. Slowly rotate the main shaft, closing the vacuum interrupter’s,
until the middle phase light is on. Adjust the insulators on the two
outside phases so that the lights on all three phases come on
Figurt 6.1. LNNstning LNcknuo
Figurt 6.2. RtmNving Clamp Stcuring LNwtr Ttrminal
Figurt 6.3. RtmNving BNlo and Shuno SuppNros
Figurt 6.4. RtmNving BNlo Stcuring Upptr Ttrminal
