TELEPHONE--
TYPE REL AY S
TEST VOLTAGE
RHEOSTAT
---
TELEPHONE
TYPE RELAY
REVERSING SWITCH
(CONTA CTS SHOWN
IN " DI RECT" POSITION)
......_TR ANSFO RMER
CHASSIS OPERATED
SHORTrNG SWITCH
-TEST SWITCH
TERMIN A L STUD
Page 5
Fig.
3
CVR-1 Voltage Regulating t<.elay Internal Schematic
settings and is the voltage which the relay
will tend to maintain. A line drop com
pensator incorporated in the relay enables
the relay to adjust the tap changer to regu
late the voltage at the load center rather than
at the tap changer itself. A current trans
former installed in the main transformer
provides a small secondary current pro
portional to the current flowing through to
the load. By thus circulating current pro
portional to the load through resistance and
reactance elements, an impedance voltage is
produced which is combined with the control
voltage to match the relation between the
transformer output voltage and the line im
pedance drop. In this manner the resultant
voltage applied to the voltage coil is made
to match the load center voltage. When
these resistance and reactance drops are
properly selected to match the line imped
ance drop, the CVR-1 relay will respond to
and regulate load center voltage rather than
the transformer output voltage.
Setting the CVR-1 Relay by Applying
an External Voltage
It is most convenient to set theCVR-1 relay
in its mounting on the tap changer panel.
The relay operating points may be set by
means of its scale which is calibrated in
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