Megger ATEC 210415 Series, Manual

Page: 42 / 82

OPERATION NOTES
35
AVTM21-415Ja Rev. A June 2005
VOLTAGE CONTROL SCALE
A reference scale is provided so that the voltage control
position can be repeated. This convenience feature is useful
when making repetitive tests such as those required on the
three-phase wires of a cable. In addition, the voltage control
scale is used to predetermine the voltage developed even
though the actual voltage buildup may lag behind the motion
of the voltage control because of the capacitance charging
effect. Using this feature minimizes the possibility of applying
excessive voltage to the apparatus being tested.
To predetermine the voltage control setting, refer to the
regulation curve given in Figure 9. The accuracy of the voltage
setting will normally be on the order of 5 to 10%, depending
on the line voltage and the nature of the apparatus being
tested.
USE OF REGULATION CURVE
The regulation curve given in Figure 9 applies when the
stabilizer is "OUT" and has been provided for convenience in
planning the adaptation of the Test Set to measurement of
various apparatus. It is also useful in adapting the Test Set to
special use such as production testing. The regulation curve
relates the output voltage control setting to the actual output
voltage and load resistance. From this curve, peak ripple
voltage can be estimated and the equivalent internal resistance
of the Test Set can be estimated for a wide variety of
circumstances. The curve also indicates the circuit breaker
limits of operation.
STEP VOLTAGE TESTING
This Test Set is well adapted to the commonly used test
procedure of increasing the voltage applied to the apparatus
being tested in steps (See Section 10 for additional data). The