S&C Mark V Instruction Sheet

6 S&C Instruction Sheet 711-590
Inspection Recommendations
Before Starting
To ensure a Mark V Circuit-Switcher’s continued proper
performance, it should be inspected in accordance with
the recommended schedule and procedures contained
in this publication. Table 1 on pages 7 and 8 indicates
the frequency with which each major circuit-switcher
component should be inspected. Table 2 on pages 9 and
10 lists a summary of inspection procedures appropriate
for each component.
These inspection recommendations are applicable to
Mark V Circuit-Switcher models having one, two, or three
interrupting gaps per pole-unit.
Recommended Inspection Schedule
A mechanical-operations test value is indicated in Table 1
on pages 7 and 8 for those Mark V Circuit-Switcher compo-
nents affected by the number of mechanical operations
performed. It is a guideline to the number of Open/Close
operations expected for the component before replace-
ment is required.
Electrical operations limits are listed for the interrupter
and disconnect live parts because these components are
affected by the number of electrical operations performed.
These limits depend on the circuit-switcher application,
magnitude of current switched and, in some cases, the
style of circuit-switcher involved. For the interrupter and
disconnect live parts, the electrical operations limit may
provide a more accurate guideline for the number of Open/
Close operations expected before replacement is required.
The actual number of Open/Close operations for a
component will depend on the nature of the application,
the environment (e.g., whether subject to temperature
or humidity extremes or highly corrosive or dusty
atmospheres), and the observance of the recommended
inspection schedule.
An inspection frequency is shown for each component.
To maximize the operating life of the component, S&C
recommends the user perform the inspection procedures in
Table 1 on pages 7 and 8 at the frequency indicated by a “ ● ”—
either in number of Open/Close operations or years, which-
ever occurs more often. If the inspection results indicate
or if dictated by the mechanical operations test value or
electrical operations limit guideline, the component should
be replaced.
Each user’s own experience will determine whether
more frequent inspections are required.
Note: For most transformer-protection applications, the
circuit-switcher inspection frequency is approximately
ve years, consistent with many utilities’ transformer-
inspection practices.

S&C Mark V Specifications

General

Brand	S&C
Model	Mark V
Category	Switch
Language	English