ABB COV-8 Beipackzettel - Seite 7

Blättern Sie online oder laden Sie pdf Beipackzettel für Relais ABB COV-8 herunter. ABB COV-8 20 Seiten. Voltage controlled overcurrent relay

Seite drucken

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

† 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