MR VACUTAP VM-Ex, Installation And Commissioning Instructions

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5 Mounting
Maschinenfabrik Reinhausen GmbH 2020 65 5293079/01 EN VACUTAP
®
VM-Ex
Vacuum-drying in the autoclave
1. Heat up the on-load tap-changer in air at atmospheric pressure with a
temperature increase of approximately 10 °C/h to a final temperature of
maximum 110 °C.
2. Pre-dry the on-load tap-changer in circulating air at a maximum tempera-
ture of 110 °C for a period of at least 20 hours.
3. Vacuum-dry on-load tap-changer at between 105 °C and maximum
125 °C for at least 50 hours.
4. Residual pressure of no more than 10
-3
bar.
5.3.6.2 Vapor-phase drying in the autoclave
For vapor-phase drying in the autoclave, you must open the kerosene drain
plug in the oil compartment base before drying so that the kerosene conden-
sate can drain from the oil compartment.
1. Unscrew kerosene drain plug in base of oil compartment counter-clock-
wise. The kerosene drain plug cannot be unscrewed all the way.
Figure 46: Kerosene drain plug
2. NOTICE! Remove the on-load tap-changer head cover (24 screws M10/
wrench size 17 with locking washers) and store it outside the autoclave.
Otherwise, the on-load tap-changer head cover may be damaged.
3. NOTICE! Remove on-load tap-changer accessories and store outside au-
toclave: motor-drive unit, drive shaft, protective relay, bevel gear, temper-
ature sensor. Otherwise, the on-load tap-changer accessories may be
damaged.
Vapor-phase drying in the autoclave
1. Supply kerosene vapor at a temperature of around 90°C. Keep this tem-
perature constant for 3 to 4 hours.