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41-201.4H
the time dial set to the indicated position, apply the
voltages specified in Table 1 (e.g., for the CV-4, 140
percent of tap value voltage) and measure the oper-
ating time of the relay. The operating time should
equal those of Table 1 plus or minus 5%. Note that
the resistor, where used in CV-8 should be shorted
when making this adjustment.
6.1.2. Indicating Contactor Switch (ICS)
Close the main relay contacts and pass sufficient dc
current through the trip circuit to close the contacts of
the ICS. This value of current should not be greater
than the particular ICS nameplate rating. The indica-
tor target should drop freely.
Repeat above except pass 85% of ICS nameplate
rating current. Contacts should not pickup and target
should not drop.
6.1.3. Trip Indicator (OI)
Pass sufficient dc current through the trip circuit to
operate the OI. This value of current should not be
greater than the particular OI nameplate rating. The
indicator target should drop freely.
Repeat above except pass 85% of OI nameplate rat-
ing current. Target should not drop.
7.0 MAINTENANCE
All relays should be inspected periodically and the
time of operation should be checked at least once
every year or at such other time intervals as may be
dictated by experience to be suitable to the particular
application.
All contacts should be periodically cleaned. A contact
burnisher Style 182A836H01 is recommended for
this purpose. The use of abrasive material for clean-
ing contacts is not recommended, because of the
danger of embedding small particles in the face of
the soft silver contact and thus impairing the contact.
7.1. CALIBRATION
Use the following procedure for calibrating the relay if
the relay has been taken apart for repairs, or the
adjustments have been disturbed. This procedure
should not be used until it is apparent that the relay is
not in proper working order (See "Performance
check").
6
7.1.1. CV Unit
Note:
A spring shield covers the reset spring of
the CV unit. To remove the spring shield,
requires that the damping magnet be
removed first. The screw connection hold-
ing the lead to the moving contact should
be removed next. The second screw hold-
ing the moving contact assembly should
then be loosened not removed.
!
CAUTION
This screw terminates into a nut held captive
beneath the molded block. If screw is removed,
difficulty will be experienced in the re-assembly
of the moving contact assembly. Slide the spring
shield outward and remove from relay. Tighten
the screw holding the moving contact assembly
to the molded block.
Contact – By turning the time dial, move the moving
contacts until they deflect the stationary contact to a
position where the stationary contact is resting against
its backstop. The index mark located on the movement
frame should coincide with the "O" mark on the time
dial. For double trip relays, the follow on the stationary
contacts should be approximately 1/64".
For relays identified with a "T", located at lower left of
stationary contact block, the index mark on the move-
ment frame will coincide with the "O" mark on the time
dial when the stationary contact has moved through
approximately one-half of its normal deflection. There-
fore, with the stationary contact resting against the
backstop, the index mark is offset to the right of the
"O" mark by approximately.020". (For the type CV-6
and CV-7 relays, the follow on the back contact should
be approximately 1/64"). The placement of the various
time dial positions in line with the index mark will give
operating times as shown on the respective time-volt-
age curves. For double trip relays, the follow on the
stationary contacts should be approximately 1/32".
Minimum Trip-Voltage — The adjustment of the
spring tension in setting the minimum trip voltage
value of the relay is most conveniently made with the
damping magnet removed.
With the time dial set on "O", wind up the spiral
spring by means of the spring adjuster until approxi-
mately 6 3/4 convolutions show.
CV Voltage Relay Class 1E
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