Preparing The Test Vessel And Electrodes; Loading The Test Vessel; Figure - Megger OTS 60PB Guide De L'utilisateur

Operation

Preparing the Test Vessel and Electrodes

1. Clean the oil test vessel thoroughly before pouring the oil sample. Methods for cleaning are usually
detailed in the national specifications for oil testing and should be adhered to. Rinsing with part of the
oil sample is normally required. The sample should be poured into the vessel, avoiding the formation
of air bubbles, up to the 500 ml level mark. (Cover the test vessel when transferring the oil from the
filling area to the Oil Test Set to prevent contamination.)
2. Clean the electrodes and all surrounding parts that come into contact with the oil sample to be tested.
Rinsing with part of the oil sample is recommended before the final filling with the oil to be tested. It
may prove to be convenient to allow the oil to stop dripping from the electrodes before removing the
oil vessel after the door has been opened. This will reduce the need for cleaning the test chamber
floor.
3. Set the gap between the electrodes according to the requirement of the testing specification being
undertaken. A spacing gauge is provided in the accessory kit for this purpose. The clamp screws at
the bottom of both electrode supports should be slackened and the sliding arms moved so that the
gap is approximately central between the two supports. Tighten the clamp screw on one support to
hold one side firmly, then adjust the other so that when the gauge is passed between the electrodes
it touches both simultaneously. Tighten the clamp screw on the second support. Make sure that the
electrodes are firmly finger tight on the threaded spindles. Recheck the gap after it has been set.

Loading the Test Vessel

1. Open the test chamber door by pulling it downward to the horizontal position.
Remove the lid (if fitted) from the filled oil vessel to be tested and slide the vessel across the door
tray into the back stop in the test chamber.
Lower the test electrodes into the oil by closing the door fully. Slowly closing the door reduces the
risk of air entrapment in the oil.
The oil sample in the test vessel is now readily for dielectric strength testing.
Note:– Upon completion of the test sequence remove the vessel from the test chamber and cover to
prevent contamination.
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