Instruction Book
Page 28
Effective: February 2007
For more information visit: www.EatonElectrical.com
I.B. 8295A61H07
Figure 5-2 Type VCP-WR Series 20 Interrupter
Assemblies
Figure 5-3 Type VCP-WR Series 18 Interrupter
Assemblies
5-2.2 CONTACT EROSION INDICATOR
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 Cutler-Hammer vacuum interrupters utilizing
copper-chrome contact material. If contact erosion
reaches 1/8 inch, the interrupter must be replaced. A
contact erosion indicator mark is located on the moving
stem of the interrupter (Figures
7-2
and
7-3
)
In order to determine if the contacts have eroded to the
extent that the interrupter must be replaced, observe the
erosion mark placed on each moving stem from the rear
of the breaker with the breaker closed. The interrupter is
satisfactory if the mark on the stem is visible with the
breaker closed. The entire interrupter assembly must be
replaced if the mark is no longer visible.
The erosion indicator is easily viewed from the rear of
the breaker on Series 18 and 29 VCP-WR breaker
elements. Because the Series 20 VCP-WR breaker
element’s interrupter assembly is inverted relative to
Series 18 and 29 configurations, the erosion indicator is
not easily viewed. It is possible to observe the Series 20
indicator using a light and a dental type mirror.
Figure 5-4 Type VCP-WR Series 29 Interrupter
Assemblies
Summary of Contents for Cutler-Hammer VCP-WR Series
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