IB
6.1.12.1-1C
1
8
ABB
600 and 800 Ampere Frames
(K-600, K-800, K-600S, K-800S, and K-800M)
1. The hex portion of the adjustment stud must be
centered within 1/16” between the yoke and the
pushrod insulator.
2. Contact pressure is established on a closed
breaker with the adjustment stud for a 5/64” to
3/32” gap at
A
in the upper window of the contact
carrier on each side as shown in Figure 6b. The
most proficient way is to slide 5/64” and 3/32”
diameter wires (go and no-go) bent at 90
°
up and
down in the slot. Close the circuit breaker. Using
the side with the larger gap, set the gap to accept
the “Go” gauge but reject the “No-Go” gauge.
Open and again slow-close the circuit breaker to
recheck the pressure. Follow each adjustment of
contact pressure by a making adjustment in step
#3. After completing step #3, the adjusted poles
may have a pressure setting greater than 3/32”;
this results in more contact pressure on these
poles, which is acceptable.
3. Slow-close the contact structure until the arcing
contacts of one pole just touch. At this point, the
arcing contacts of the other two poles should be within
1/32” of touching (same idea for a two pole breaker).
If not within 1/32”, then turn the adjustment stud of
these two poles in the direction to increase pressure
until all three poles touch within 1/32”. Should the
pressure be too excessive to allow the breaker to
latch closed, return to the first making pole, decrease
its pressure by 1/8 revolution (CW), and recheck the
simultaneous-make. Repeat in increments of about
1/8 revolution for no more than 1/2 revolution of the
adjusting stud on the first make pole, until the breaker
latches closed.
If for any reason the contact structure is removed from
the breaker, upon assembly, reapply clean NO-OX-ID
“A-Special” to the ends of the contact bushing. Torque
the nut of the hinge joint between 15 and 25 lb-ft to
maintain the continuous current rating of the circuit
breaker.
1600 A and 2000 A Circuit Breakers
(K-1600, K2000, K1600S, K2000S, K-1600M, and
K2000M)
The main contact adjustment is to be made with the
breaker in the latched closed position. Contact
pressure is established by turning the adjustment stud
until a go-gauge will just fit the space
A
at the rear of
the moving main contacts as illustrated in Figure 6c.
Set at 3/4” [+0”, -1/64”].
After making this adjustment in contact pressure,
open the circuit breaker, re-close the circuit breaker
normally, and recheck the gap
A
. Readjust if
necessary.
Open the circuit breaker and slow-close the contacts
until the arcing contacts of one pole just touch. The
remaining poles should then be adjusted for
simultaneous-make by advancing the adjustment stud
until all poles touch within 1/32” of one another. The
contact pressure will increase on the adjusted poles
as evidenced by a pressure setting of less than 3/4”;
this results in more contact pressure on these poles,
which is acceptable.
For 2000 ampere breakers (tulip style primary
disconnects), if the primary disconnect stud is
removed, retorque the stud to 110 lb-ft.
