Renewal Parts - ABB COV-6 Instruction Leaflet

Voltage controlled overcurrent relay
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COV Voltage Controlled Overcurrent Relay
tional one-half turn. The clamp holding the sta-
tionary contact housing need not be loosened
for the adjustment since the clamp utilizes a
spring-type action in holding the stationary
contact in position.
C. The sensitivity adjustment is made in two
steps:
1) The adjustable resistor, located at the top left
of the voltage unit, is adjusted such that the
maximum resistance is in the circuit (approxi-
mately 2500 ohm).
2) The tension of the spiral spring, attached to
the moving element assembly, is then varied.
The spring is adjusted by placing a screw-
driver or similar tool into one of the notches
located on the periphery of the spring
adjuster and rotating it. The spring adjuster is
located on the underside of the bridge and is
held in place by a spring type clamp that does
not have to be loosened prior to making the
necessary adjustments.
The spring is to be adjusted such that the contacts
will close (indicated by pickup of telephone relay "T")
when the applied voltage is reduced to 80 volts. The
contacts should open with 80 plus volts applied.
Any setting other than the 80 volts then can be made
by adjusting the resistor for the desired contact clos-
ing voltage.
8.3
INDICATING CONTACTOR SWITCH (ICS)
Initially adjust unit on the pedestal so that armature
fingers do not touch the yoke in the reset position
(viewed from top of switch between cover and frame).
This can be done by loosening the mounting screw in
the molded pedestal and moving the ICS in the
downward position.
Frequency
60
† Volt-Ampere burden is average for the various settings
ENERGY REQUIREMENTS
VOLTAGE UNIT
Drop-out
Adjustment Volts
Volts Continuous
80-100
.
a) Contact Wipe – Adjust the stationary contact so
that both stationary contacts make with the
moving contacts simultaneously and wipe 1/64"
to 3/64" when the armature is against the core.
b) Target – Manually raise the moving contacts and
check to see that the target drops at the same
time as the contacts make or up to 1/16" ahead.
The cover may be removed and the tab holding
the target reformed slightly if necessary. How-
ever, care should be exercised so that the target
will not drop with a slight jar.
c) Pickup – The unit should pickup at 98% rating
and not pickup at 85% of rating. If necessary, the
cover leaf springs may be adjusted. To lower the
pickup current use a tweezer or similar tool and
squeeze each leaf spring approximate equal by
applying the tweezer between the leaf spring and
the front surface of the cover at the bottom of the
lower window.
If the pickup is low, the front cover must be
removed and the leaf spring bent outward
equally.
8.4
TELEPHONE RELAY (T)
No calibration is required. The telephone relay
should have a dropout time of 250 msec. ±50 msec.

9.0 RENEWAL PARTS

Repair work can be done most satisfactorily at the
factory. However, interchangeable parts can be fur-
nished to the customers who are equipped for doing
repair work. When ordering parts, always give the
complete nameplate data.
Class 1E certification of a repaired relay is the
responsibility of the agent who makes the repair.
Volt-Ampere
Maximum
at 120 Volts
132
Drop-out
Burden
Ratio
8.0
98%
41-116.1C
7

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