Eaton 50 VCP-TR16, Инструкция по использованию

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Instruction Book
Effective: November 2017 Page 34
For more information visit: www.Eaton.com IB131016EN
into service (Figures 3-5 and 3-6). Other barriers may
also be required in keeping with paragraph 4-3.
The current transfer system consists of a unique
flexible connector attached to the movable stem of
the vacuum interrupter. The flexible connector
consists of a large
Figure 5-4 Typical Fixed 50 VCP-TR Interrupter
Assembly
Figure 5-5 Typical Drawout 150 VCP-T Interrupter
Assembly
number of flexible leaf conductors that are pressure
welded on both ends. One end of the flexible connector
is attached to the movable vacuum interrupter stem and
the other end to the circuit breaker's lower conductor.
As the vacuum interrupter stem moves and the flexible
connector flexes, current is safely and efficiently
transferred between the stem and lower conductor.
5-2.1 CONTACT EROSION INDICATOR (Up to 25kA)
The purpose of the contact erosion indicator is to
monitor any erosion of the vacuum interrupter
contacts. Contact erosion is, however, very minimal
over time with Eaton vacuum interrupters. A contact
erosion indicator mark is located on the moving stem
of the interrupter (Figure
6-1). The erosion mark can
be observed from the rear of the circuit breaker, and
should be done with the circuit breaker closed. If the
erosion mark is no longer visible with the circuit
breaker closed, the entire vacuum interrupter
assembly must be replaced.
5-2.2 CONTACT WIPE AND STROKE (Up to 25kA)
Contact wipe is the indication of (1) the force holding
the vacuum interrupter contacts closed and (2) the
energy available to hammer the contacts open with
sufficient speed for interruption.
Stroke is the gap between fixed and moving contacts
of a vacuum interrupter with the breaker open.
The circuit breaker mechanism provides a fixed
amount of motion to the drive insulators. The first
portion of the motion is used to close the contacts (i.e.
stroke) and the remainder is used to further compress
the preloaded contact spring. This additional
compression is called wipe.
Wipe and stroke are thus related to each other. As the
stroke increases due to the erosion of contacts, the
wipe decreases. A great deal of effort has been spent
in the design of all Eaton vacuum circuit breakers, in
order to eliminate the need for field adjustments of
wipe or stroke. Refer to paragraph 6-7 for details on
visually inspecting contact wipe.
5-2.3 CONTACT WIPE AND EROSION (40KA)
Direct reading contact erosion indicators are not
provided on 40Ka VCP-T and VCP-TR breakers. The
contact wipe is measured using a dialed caliper as
described in paragraph 6-5.1. Acceptable or
unacceptable contact erosion is determined from the
contact wipe measurement.
The vacuum interrupters on 40kA breakers are not
visible from the rear of the circuit breaker without
removing the individual rear covers (Figure
3-8 ) . The
rear covers are held in place by the upper and lower
primary conductors which must be removed first to
access the