Download Print this page

Maintenance - Siemens GMSG-GCB Instruction Manual

5 kv to 15 kv vacuum circuit breakers


Note: A preventive
maintenance program is not
intended to cover
reconditioning or major repair,
but should be designed to
reveal, if possible, the need for
such actions in time to prevent
malfunctions during operation.


Introduction and maintenance intervals
Periodic inspections and maintenance are
essential to safe and reliable operation of the
type GMSG vacuum circuit breaker.
When the type GMSG vacuum circuit breaker
is operated under "usual service conditions,"
maintenance and lubrication is recommended
at ten-year intervals or at the number of
operations indicated in Table 2: Maintenance
and lubrication schedule on page 40.
"Usual" and "unusual" service conditions for
medium-voltage metal-clad switchgear are
defined in ANSI/IEEE C37.20.2, section 8.1
and C37.04, section 4 together with C37.010,
section 4 for type GMSG non-generator circuit
breakers. For type GMSG-GCB generator
circuit breakers, these service conditions are
defined in ANSI/IEEE C37.20.2, section 8.1
and ANSI/IEEE C37.013, section 4.2
Generally, "usual service conditions" are
defined as an environment where the
equipment is not exposed to excessive dust,
acid fumes, damaging chemicals, salt air,
rapid or frequent changes in temperature,
vibration, high humidity and extreme
The definition of "usual service conditions" is
subject to a variety of interpretations.
Because of this, you are best served by
adjusting maintenance and lubrication
intervals based on your experience with the
equipment in the actual service environment.
Hazardous voltage and high-speed moving parts.
Will cause death, serious injury and property damage.
Do not by-pass interlocks or otherwise make interlocks inoperative.
Interlocks must be in operation at all times.
Read instruction manuals, observe safety instructions and use
qualified personnel.
Regardless of the length of the maintenance
and lubrication interval, Siemens
recommends the circuit breaker should be
inspected and exercised annually.
For the safety of maintenance personnel as
well as others who might be exposed to
hazards associated with maintenance
activities, the safety-related work practices of
NFPA 70E (especially chapters 1 and 2) should
always be followed when working on
electrical equipment.
Maintenance personnel should be trained in
the safety practices, procedures and
requirements that pertain to their respective
job assignments.
This instruction manual should be reviewed
and retained in a location readily accessible
for reference during maintenance of this
The user must establish a periodic
maintenance program to ensure trouble-free
and safe operation.
The frequency of inspection, periodic
cleaning and preventive maintenance
schedule will depend upon the operation
conditions. NFPA Publication 70B, "Electrical
Equipment Maintenance" may be used as a
guide to establish such a program.



Subscribe to Our Youtube Channel