MA-005 - Minitrans Installation Manual - Rev 4.5
13-Aug-20
Page 21 of 86
8.1
Transformer Valves
Figure 8-3 shows the location of the following valves:
Figure 8-3: Possible valve locations of a transformer
8.1.1
Fill valve
If the transformer is nitrogen blanketed, the fill valve or any other valve at the top of the
transformer should not be used as an oil supply valve because there is no guarantee that
there will always be oil at this position. However, it is acceptable to return oil through
this valve.
8.1.2
Drain valve
The drain valve may be used as an oil supply or oil return valve. However, it is particularly
useful to return the oil to the transformer through this valve because it is near ground
level, providing an easily accessible point to bleed the air from the oil lines during the
installation.
8.1.3
Ancillary valves
Some transformers have an array of ancillary valves and ports. These valves can be a
good choice to connect the product to the transformer, although it is important to know
how these valves route inside the transformer.
Ensure that the valve chosen to return oil is not internally piped to another
location within the transformer, such as the headspace or the internal
windings.
