GE IBCG51M, Инструкция по эксплуатации

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GEK-49822
because of the insufficient range of the variable resistor, it should
necessary to wind up the control spring adjuster more than 30 degrees (one
unwind it more than 90 degrees (three notches) from the factory
never be
notch) or
Test connections for making pickup and time checks on the time over-current unit are
shown in Fig. 22 and 23. Use a source of
volts or greater with good wave form and
constant frequency.
transformers or phantom loads should not be employed in
testing induction relays since their use may cause a distorted wave form. The contact
in the wound shading coil circuit marked D, see internal connection diagram, must be
blocked closed or for both the pickup test and the time test.
Time Setting
The setting of the time dial determines the length of time the unit requires to
close its contacts when the current reaches a predetermined value. The contacts are
just closed when the dial is set on 0. When the dial is set on
the disk must travel
the maximum amount to close the contacts and therefore this setting gives the maximum
time setting.
The primary adjustment for the time of operation of the unit is made by means of the
time dial. However, further adjustment is obtained by moving the permanent magnet
along its supporting shelf; moving the magnet toward the disk shaft decreases the time,
while moving it away increases the time.
Be sure the magnet never extends out beyond
the cutout in the disk.
Pickup Test
Use rated frequency for both the pickup and time tests.
Set the relay at the 0.5 time dial position and 2.0 ampere tap. Using the
connection in Fig. 22, the main unit should close its contacts within percent
tap value current amps).
Time Test
Set the relay at No. 5 time dial setting and the 2.0 amp tap. Using the test
connection in Fig. 23, apply five times tap current (10.0 amp) to the relay. The relay
should operate within the limits given in Table 12.
TABLE 12
TOC UNIT OPERATING TIME
LIMITS
Time in Seconds
Relay Type
Min. Midpoint Max
1.72 1.78 1.83
1.27 1.31 1.35
0 . 8 9
0.92 0.95
*Indicates Revision
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