Servicing; Control-Spring Adjustments - GE CEY51A Instructions Manual

GEK-1275
resembling in effect a superfine file. The polishing action is so delicate that no
scratches are left, yet it will clean off any corrosion thoroughly and rapidly. Its
flexibility ensures the cleaning of the actual points of contact. Do not use
knives, files, abrasive paper or cloth of any kind to clean relay contacts.
SERVICING
If it is found during the installation or periodic tests that the mho unit
calibrations are out of limits, they should be recalibrated as outlined in the
following paragraphs. It is suggested that these calibrations be made in the
laboratory. The circuit components listed below, which are normally considered as
factory adjustments, are used in recalibrating the units. These parts may be
physically located from Figure 1A and lB. Their locations in the relay circuit are
shown in the internal connection diagrams of Figure 9.
Rl1 - 01-2 Unit ohmic reach adjustment
Xl1 - 01-2 Unit angle of maximum torque adjustment
R12 - 02-3 Unit ohmic reach adjustment
X12 - 02-3 Unit angle of maximum torque adjustment
R13 - 03-1 Unit ohmic reach adjustment
X13 - 03-1 Unit angle of maximum torque adjustment
NOTE: Before making pickup or phase-angle adjustments on the mho units, the
units should be allowed to heat up for approximately 15 minutes energized with rated
voltage alone and the restraint tap leads set for 100%. Also it is important that
the relay be mounted in an upright position so that the units are level.
CONTROL SPRING ADJUSTMENTS
Make connections to the relay as shown in Figure 10. Set the restraint-tap
leads and the basic-reach taps as shown in Table IX. Make sure that the relay is in
an upright position so that the units are level. With the current set at 5 amperes
and the voltage VA-B at 120 volts, set the phase shifter so that the phase-angle
meter reads the value shown in Table XII.
Now reduce the voltage to the test voltage value and set the current at the
value shown in Table XII for the unit being adjusted. Insert the blade of a thin
screwdriver into one of the slots in the edge of the spring-adjusting ring and turn
the ring until the contacts of the unit just close. If the contacts were closing
below the set point shown in Table XII, the adjusting ring should be turned to the
right. If they were closing above the set point, the adjusting ring should be
turned to the left.
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