Mechanism - ABB K-Line Plus KP-8 Installation & Maintenance Instructions Manual

ABB
Figure 8 - Contact Adjustment
or are within 0.032 inch of each other.
The contacts should now be in correct adjustment and
the breaker may be put in service.
adjustment is necessary for "simultaneous" make, the
contact pressure will increase on those adjusted poles.
Thus, a dimension of less than that specified above
indicates more contact pressure, which is acceptable if
achieved using the above procedure.

MECHANISM

The following adjustment values are approximate, and
may have to be altered slightly to account for
manufacturing tolerances, wear during use, etc.
Trip Latch Engagement (Bite) (Refer to Figure 9)
The latch engagement adjusting screw (3) is located to
the right of the right-hand mechanism housing (1). It
can be reached easily from the top of the circuit
breaker. To adjust the latch (2) engagement, proceed
as follows:
1. Back off adjusting screw (3) to assure excessive
latch engagement.
2. Close the circuit breaker.
3. Turn adjusting screw (3) down slowly until the latch
just releases, tripping the circuit breaker.
4. Back off the adjusting screw (3) approximately two
full turns.
Tripper Bar Latch Engagement (Refer to Figure 9)
The tripper bar latch engagement adjusting screw (4) is
located adjacent to the latch engagement adjusting
Note that if an
screw (3). To adjust the tripper bar latch engagement,
proceed as follows:
1. Back off the adjusting screw (4) to assure excessive
tripper bar travel.
2. Close the circuit breaker.
3. Turn the adjusting screw (4) down slowly until the
latch just releases, tripping the circuit breaker.
4. Back off the adjusting screw (4) approximately 3½
turns.
Tripper Bar Load (Refer to Figure 9)
The tripper bar load is measured by the use of a spring
scale positioned as shown. The tripper bar load should
be no greater than 50 ounces.
Shunt Trip Adjustment (Refer to Figure 10)
Note: This procedure should only be performed when
the shunt trip has malfunctioned or been replaced.
Caution: Perform this procedure only on an open circuit
breaker with its closing springs discharged.
1. Locate the shunt trip adjusting screw (1). It can be
accessed with a long screwdriver from the top of the
breaker.
Figure 9 - Latch Engagement and Tripper Bar
Latch Engagement Adjustments
IB 6.2.11.1-1C
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