GE IBCG51M, Инструкция по эксплуатации

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GEK-49822
The'extremely inverse time overcurrent unit is of the wattmetric type similar to
that used in meters except as follows:
the upper portion of the lron
structure has two concentric windings on the middle leg of the magnetic circuit.
of these is a tapped current winding connected to taps on the tap block; the other a
floating winding which is connected in series with the directional unit. contacts, a
resistor, a capacitor and the two coils on the lower legs of the magnetic circuit. When
power flow is in such a direction as to close a directional unit contact, the unit
develops torque on the operating disk.
The disk shaft carries the moving contact which completes the trip circuit when it
touches the stationary contact or contacts. The shaft is restrained by a spiral spring
to give the proper contact-closing current, and its motion is retarded by a permanent
magnet acting on the disk to produce the desired time characteristic.
The variable
retarding force resulting from the gradient of the spiral spring is compensated by the
spiral shape of the induction disk, which results in an increased driving force as the
spring winds up.
TARGET SEAL-IN UNIT
A seal-in unit is mounted on the left side of the time overcurrent unit. This unit
has its coil in series and its contacts in parallel with the main contacts of the
overcurrent unit, arranged in such a manner that when the main contacts close, the
seal-in unit picks up and seals-in around the main contacts.
When the seal-in unit
operates, it raises a target into view which latches up and remains exposed until
manually released by pressing the button located at the lower left corner of the cover.
INSTANTANEOUS UNIT
The IOC unit is a small hinged armature type instantaneous element and is mounted on
the right side of the TOC unit. The IDC element operates over a total range
obtained by using a tapped coil which provides a five-to-one low range and a
one high range; this combination provides the total range. When the current
reaches a predetermined value, the instantaneous element operates closing its
circuit and raising its target into view. The target latches in the exposed position
until it is released.
The same button that releases the target seal-in unit
releases the target of the instantaneous unit.
RECEIVING. HANDLING AND STORAGE
These relays, when not included as part of a control panel will be shipped in
cartons designed to protect them against damage. Immediately upon receipt of a relay,
examine it for any damage sustained in transit. If injury or damage resulting from
rough handling is evident, file a damage claim at once with the transportation company
and promptly notify the nearest General Electric Apparatus Sales Office.
Reasonable care should be exercised in unpacking the relay in order that none of
the parts are injured or the adjustments disturbed.
If the relays are not to be installed they should be stored in their
original cartons in a place that is free moisture, dust and metallic chips.
Foreign matter collected outside of the case may find its way inside when the
cover is removed, and cause trouble in the operation of the relay.
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