5 Mounting
Maschinenfabrik Reinhausen GmbH 2020
55
4983703/01 EN
VACUTAP
®
VV-Ex
2. Unscrew kerosene drain plug in base of oil compartment clockwise. The
kerosene drain plug cannot be unscrewed all the way.
Figure 30: Kerosene drain plug
3. Insert on-load tap-changer insert. Please request the documents for in-
stallation from Maschinenfabrik Reinhausen GmbH.
4. Connect pipe connections R and Q of on-load tap-changer head to the
kerosene vapor lead using one shared lead.
Figure 31: Kerosene vapor lead
5. Seal off unused pipe connections and pipe bends with a suitable blank
cover.
Vapor-phase drying in the transformer tank
1. Supply kerosene vapor at a temperature of around 90°C. Keep this tem-
perature constant for 3 to 4 hours.
2. Increase the kerosene vapor temperature by approx. 10°C/hour to the de-
sired final temperature of max. 125°C at the on-load tap-changer.
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.
After drying, proceed as follows to close the kerosene drain plug again:
1. Remove on-load tap-changer insert.
