MA-001 – TRANSFIX-family Installation Manual – Rev 3.0
18-Jan-16
Page 23 of 55
Do not
use galvanised steel, copper or plastic fittings as these materials can
negatively affect the gas concentrations in the sample line.
All pipe fittings should be tight and all threaded pipe fittings tightly wrapped with
PTFE tape with a light coating of PTFE paste or other quality pipe thread sealant
applied over the taped male threads to prevent leaks. Both of these items are
included in the product installation kit.
Note: GE recommends two wraps of PTFE tape or
three wraps for large pipe fittings.
8.3.4
Connection to Oil Return Valve
Oil is typically returned to a valve lower on the transformer, such as the transformer drain
valve.
Note: The distance from the oil supply valve should be at least 30 cm (12 in.).
Do not
return the oil into a high pressure area on the transformer, such as a
cooling loop.
The following points must be observed when connecting to the oil return valve (see
Section 8.1 for information on valve selection):
The return line to the transformer must be via the Return Assembly (see Figure 8—
10 to Figure 8—12). This assembly incorporates a check valve and port that
facilitates bleeding the system of air during the installation process. The bleed port
must be oriented up so that air can be drawn from the top. The assembly can be
reconfigured to fit the transformer valve and adaptor. This assembly must be
adapted from a ¼ in. female NPT fitting to the valve on the transformer.
Figure 8—10: Bleed assembly on flange-type oil return valve
Check Valve
Bleed Port
(must be oriented upwards)
