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Time Settings
The s etting of the time dial is what primarily determines the time of the relay
operation.
Further adjustment is obtained by moving the permanent magnet along its
s upporting s helf.
operating time; moving it out increases the operating time.
Figures 2, 3, and 4 s how the time-voltage characteris tics of the various relays
with
the
time-dial
s ettings ,
s et
the
characteris tics )
by turning it until the number lines up with the notch 1.n the
adjacent frame.
The time indicated by the curves is the time required to clos e the
relay contacts
when the voltage is
above, to the value on the curve.
The time-voltage curves are plotted 1.n percent, making them applicable for all
tap s ettings .
At the time
contacts , loos e s crews , or other imperfections .
made in the manner described in the s ection on maintenance.
Before putting the relay into s ervice, a check s hould be made to determine that
factory adjus tments have not been dis turbed.
dials will be s et at zero before the relay leaves the factory.
be changed s o that the relay contacts may be opened.
The dropout voltage s hould be checked on one or more taps to make certain that
the contacts
clos e.
s ettings .
Recommended tes t connections for .the above tes ts are s hown in Figure 9.
The relay may be tes ted while mounted on the panel,
another s ource of power,
connecting plugs .
been laboratory tested.
Thes e relays
dis turbed.
If they are,
original s ettings .
Moving the magnet in towards the back of the relay decreas es the
s ettings
for
obtaining
time
dial
to
of
ins tallation,
The time voltage curves
by ins erting s eparate
Or, the cradle can be drawn out and replaced by another that has
MAINTENANCE
are adjus ted at the factory and the adjus tments s hould not be
the following points s hould be obs erved in res toring the
GEH-1768
each
characteris tic.
the
number
required
s uddenly decreas ed,
INSPECTION
the relay s hould
Corrections to the relay s hould be
OPERATION
On relays that have time dials ,
s hould be checked for one or more
testing
8
To
make
(to
give
the
from
operating value or
be
ins pected
for
This s etting s hould
either from its own or
plugs
in
place
time
desired
tarnis hed
the
of
the
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