Megger 128311841, Руководство по эксплуатации

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Operating Manual
12
HV Tester 25 kV
4.2 OPERATING PROCEDURE
4.2.1 Performing measurements
When the mains key switch is turned on, the white pilot lamp (Figure 4
p. 11 [4]) lights up. If the equipment is grounded properly, the yellow
pilot lamp also lights up.
If this does not happen, the HV Tester still has to be grounded
(protective conductor terminal).
This pilot lamp [5] signals proper connection of the station and
protective grounds independently of the high voltage being connected.
The equipment will only work when both lamps are lit and the timer is in
action.
The illuminated green
"HV on" [6] button switches the high voltage on
if the HV adjuster [3] in zero position at left stop (second switching
operation, interlock, forced zero position).
Tip: If you want to select testing times shorter than 5 min, turn the
rotary knob of the timer first beyond the position "5" and then to
the desired time.
The red illuminated "HV off" [7] button lights up at the same time,
indicating that the "high voltage is switched on".
The test voltage can now be set by
slowly turning the adjuster
anticlockwise. While doing this, remember to follow the increase in
voltage and current on the instruments.
The output current can be measured in two measuring ranges (0.2 mA,
2 mA), which can be set using a selector switch [10].
In the central switch position (Auto), the measuring range is changed
automatically.
The relevant LED indicates the selected measuring range.
N.B.: The end stage of the HV Tester is secured against thermal
overload by a reverse voltage divider. In case of overload (e.g.,
short-circuit at the output), the output current is reduced to a
value of about 0,5 mA.