GE Industrial Solutions PowerVac PV-VL 13.8-1000-0 and -1 - Manual (Page 33)

GEH 6468A - Power/Vac VL Breaker Page 33
ING 40 kV. IN THIS CASE, SOME PERFECTLY
GOOD BOTTLES CAN SHOW A RELATIVELY
HIGH LEAKAGE CUR-RENT SINCE IT IS THE
PEAK VOLTAGE OF 120 kV THAT IS
PRODUCING ERRONEOUS BOTTLE LEAKAGE
CURRENT. IN ADDITION, ABNORMAL X-
RADIATION WILL BE PRODUCED.
An acceptable AC high potential machine is avail-
able from: GE Company, Burlington, Iowa, Catalog
Number 282A2610P001. The following machines
are also acceptable.
AC machines:
Hipotronics Model 7BT 60A
Hipotronics Model 60HVT
Biddle Cat. 222060
Phoenix Model 7BT 60A
DC machines: Hipotronics Model 860PL
Hipotronics Model 880PL
12.5. INSULATION TESTS
The primary circuit insulation on the breaker may
be checked phase to phase and phase to ground
using a 2500 Volt or other suitable megohmeter.
Since definite limits cannot be given for
satisfactory insulation values, a record should be
kept of the megohmeter readings as well as
temperature and humidity readings. This record
should be used to detect any weakening of the
insulation from one check period to the next.
Generally, readings should equal or exceed 10,000
megohms.
To measure the breaker secondary circuit
insulation resistance, disconnect the motor leads
and thread a wire connecting together all
secondary coupler pins. The measurement is made
by connecting a 500 Volt megohmeter from the
wire to ground.
13. CHECKING AND INSTALLING BREAKERS
Roll the PV-VL breaker into the cell (frame & top
plate). If the breaker stored energy springs were
charged, the spring discharge lever, located on the
left side of the breaker, will be actuated by the
spring discharge bracket and discharge the stored
energy springs, (closing and opening springs). The
yellow semaphore on the front of the breaker will
indicate “DISCHGD”.
The breaker cannot be closed when it is fully
inserted into the cell, in the lowered position.
The breaker may be operated electrically when in
the lowered position by completely removing it
from
the cubicle and connecting the breaker test coupler
accessory set (optional). The breaker functions
may now be checked electrically or manually via
the breaker control switch on the switchgear unit,
or the manual push buttons on the breaker front.
14. MAINTENANCE
14.1. GENERAL
POWER/VAC VL circuit breakers have been
designed to be as maintenance-free as practicable.
They include features such as sealed vacuum
interrupters and long-life synthetic greases which
contribute to many years of trouble-free per-
formance with a minimum amount of maintenance.
If maintenance on the PowerVac ® VL breaker is
being performed to an extended schedule such as
a 5-year or 10-year program,
the vacuum
inter-rupter integrity test should be performed if the
breaker is removed for reasons other than
scheduled breaker maintenance, and it has been
more than one year since the last vacuum integrity
test, a test should be performed.
Both long and short term maintenance of all
electrical equipment is essential for reliability and
safety. Maintenance programs MUST be custom-
ized to the specific application, well planned, and
carried out consistent with both industry experience
and manufacturer’s recommendations. Local en-
vironment must always be considered in such
programs, including such variables as ambient
temperatures, extreme moisture, number of
operations, corrosive atmosphere or major insect
problems and any other unusual or abusive
condition of the application.
One of the critical service activities, sometimes
neglected, involves the servicing and calibration of
various control devices. These devices monitor
conditions in the primary and secondary circuits,
sometimes initiating emergency corrective action
such as opening or closing circuit breakers. In view
of the vital role of these devices, it is important that
a periodic test program be followed. As was
outlined above, it is recognized that the interval
between periodic checks will vary depending upon
environment, the type of device and the user’s
experience. It is the General Electric recom-
mendation that, until the user has accumulated
enough experience to select a test interval better
suited to his individual requirements, all significant
calibrations should be checked at an interval of
one to two years.