5 Mounting
Maschinenfabrik Reinhausen GmbH 2020
159
7545652/00 EN
VACUTAP
®
VR-Ex
3. Screw the on-load tap-changer head cover onto the on-load tap-changer
head.
Figure 178: On-load tap-changer head cover
5.4.8 Drying on-load tap-changer in transformer tank
Dry on-load tap-changer in accordance with the following instructions to en-
sure the dielectric values assured by MR on the on-load tap-changer.
If you want to dry the on-load tap-changer in the transformer tank, fully as-
semble the transformer first and then undertake drying.
If drying in the transformer tank, the following methods are possible:
▪ Vacuum-drying
▪ Vapor-phase drying
As an alternative to drying the on-load tap-changer in the transformer tank, it
can also be dried in an autoclave.
5.4.8.1 Vacuum-drying in the transformer tank
The on-load tap-changer head cover remains closed during the entire drying
process.
1. Establish a connecting lead between either connections E2 and Q or con-
nections E2 and R on the on-load tap-changer head.