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MOG ( magnetic oil gauge ) of Transformer

The MOG (Magnetic Oil Gauge) is a device by which we can supervise the level of liquid/oil inside the tank or conservator of power transformer and also gives us an alert low oil level indication with making mercury switch. It is connected at the bottom of the conservator tank which is shown in figure.

Construction & Working:

The Construction & Working of MOG is given below. The magnet of MOG consists inside the conservator drives and the magnet positioned is fixied outside of the conservator tank of power transformer. The driving magnet rotates and acquires position corresponding to height of oil level as it is link with the float. The float is hinged and swings up or down when oil level rises or falls. This rise or falls rotates the driving magnet clockwise or anticlockwise with the help of bevel gear. The follower magnet carries a pointer & a cam. The pointer reads oil level and cam is set to operate the switch of predetermined low level which is shown in fig -2.

Fig-2

Calibration:

The standard calibration of dial of MOG are Empty , ¼, ½, ¾, and Full. Calibration of marks Empty & Full is done after leaving 65 mm from bottom and top of conservator to avoid striking of float to conservator wall.

Mounting:
Indicator can be mounted in titled position towards ground ( max 30⁰C )for easy viewing by fixing mounting pad at desired angle or the indicator can be mounted by keeping dial and mounting pad in vertical position. The position of indicator on the conservator can be selected to suit site condition.
Alarm Circuit:
One normally open mercury switch is provided for annunciation low level Alarm.

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