Stud shield modification, Remounting primary disconnects, Modification of the lower stud shields – GE Industrial Solutions ProTrip Conversion Kits AK-15, AK-25, and AKU-25 User Manual

Page 15: Primary disconnect modification for ak-15 breakers

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15

Stud Shield Modification

Modify the left- and right-pole lower stud insulator shields
as illustrated in Figure 24. Remount on the back plate
using the original screws and special nuts supplied with
the kit.

Remounting Primary Disconnects

On draw-out breakers, remount the primary disconnect
fingers to the new lower studs.

On AK-15 breakers only, use the following procedure to
modify the primary disconnects, as illustrated in Figure
25.

1. Place the spacer with the off-center hole in the hole

in the stud, while sliding the new retainer completely
over the stud.

2. Place the new retaining ring on the stud. Insert the tip

of the upper fingers under the retaining ring and
place the bow-tie spacers in the fingers.

3. Place the retainer over the upper fingers and insert

the bolt.

4. Inset the tip of the lower fingers under the retaining

ring and place the bow-tie spacers in the fingers.
Locate the lower retainer to hold the bow-tie spacers
in place.

5. Place the cylindrical spacer and spring on the bolt

and secure it with a washer and nut.

6. Tighten the nut to obtain 60–70 pounds of pressure

per set of four fingers when the fingers are spread

1

/

2

inch apart. If a pressure gauge is not available,
compress the spring to

13

/

16

inch to obtain proper

pressure.

CAUTION: Adequate primary contact force is essential.
Tighten the nuts on the

1

/

4

× 20 mounting bolts to obtain

a spring dimension of

13

/

16

to

27

/

32

inch. The proper

distance between the contact fingers is

7

/

16

inch. Proper

contact force is 60–70 pounds, with the contacts spread
to

1

/

2

inch.

Figure 24 Modification of the lower stud shields.

Figure 25. Primary disconnect modification for AK-15

breakers.

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