Mechanical operation
After parts have been replaced, or after the operating
sequence has been changed, it is necessary to verify and
fine-tune the operation of the recloser. This fine-tuning
procedure requires a suitable tester to apply the required
test currents. The fine-tuning procedure begins with
adjustment of the pump piston shell (to produce the proper
number of fast operations), and concludes with adjustment
of the trip linkage (to produce the proper number of
operations to lockout).
Pump piston adjustment
If the recloser fails to perform the correct number of fast
operations, it will be necessary to adjust the position of the
pump piston shell, on the pump piston.
●
●
Turning the pump piston shell off the piston, to increase
the effective length of the piston, will cause the ports
in the cylinder wall to be covered earlier during the
downward stroke of the pump; as a result more oil will be
pushed into the trip piston cylinder and the trip piston will
raise more (reducing the number of fast operations).
●
●
Turning the pump piston shell onto the pump piston, to
decrease the effective length of the piston, will cause
the ports to remain open longer during the downward
stroke of the pump; as a result less oil will be pushed
into trip piston cylinder and the trip piston will raise less
(increasing the number of fast operations).
Adjustment of the pump piston shell is a trial-and-error
procedure that must be done with a suitable tester.
Refer to
Reference R280-90-2 Low Voltage A-C Testing of
Hydraulic Reclosers
for additional information. The tester
should be adjusted to provide a minimum of four-times the
continuous current coil rating of the recloser being tested.
Use the following test procedure to perform the piston
shell adjustment:
Notee:
Prior to performing this adjustment procedure
it will be necessary to drill out the stake punch
that secures the pump piston shell to the pump
piston, see Figure 23. As an initial starting guide:
When the recloser is adjusted for a “B” timing
curve approximately 1/4 of the pump cylinder ports
should be covered by the piston shell, when set
for a “C” curve approximately 1/2 of the ports
should be covered, and when set for a “D” curve
approximately 3/8 of the ports should be covered.
1. Move the yellow manual operating handle to the
CLOSED position and wait at least three minutes for
trip piston to fully reset.
2. Operate tester (per manufacturer’s directions) to apply
the required current through the recloser. Note the
sequence and number of operations.
Stake punch
Figure 23 . Drilling out stake punch in pump piston shell
otee:
N
During fast operations recloser contact will open
almost immediately after test current is applied.
During delayed operations a noticeable delay will be
observed before the recloser operates. When lockout
occurs the yellow manual operation handle will drop
down. The trip times recorded for all fast operations
should be almost identical.
3. The number of fast and delayed operations should
match the data plate specifications. If the sequence
does not match, check to see if recloser is correctly
configured. If configuration is correct, the problem may
be either a mis-adjusted pump piston or an oil leak.
otee:
N
If the recloser operates too many, of too few, times
to lockout it will be necessary to adjust the trip
linkage to achieve the correct number of operations
to lockout. It may be necessary to readjust the piston
shell and trip linkage several times to obtain proper
sequence and time characteristics.
A. Inspect upper coil gasket and replace if damaged
or worn. Repeat test.
B. If recloser is performing too many fast operations,
turn piston shell counterclockwise a little (off the
pump piston) see Figure 24. Repeat test.
C. If recloser is performing too few fast operations,
turn piston shell clockwise a little (onto the pump
piston) see Figure 24. Repeat test.
Types V4L and V4E single-phase maintenance instructions
16
MAINTENANCE INSTRUCTIONS
MN280055EN May 2017
