MIDEL 7131 is a synthetically
optimized ester which conforms to IEC 61099 ’Specification
for unused synthetic organic esters for electrical purposes’.
Midel is used mostly in transformers and other electrical
equipment that require very specific product properties:
It is classed as
K3-high fire point fluid, which makes it suitable
for use indoors or in tunnels. In many high-risk
locations, such as the London Underground, Midel
has been used for many years.
MIDEL® 7131 has
an excellent safety record. Since it has been introduced
nearly 30 years ago, it has been used worldwide
in transformers without ever having been reported
as the cause of a fire in a building or a fluid
pool fire. In addition to this reliability track
record, a lifetime cost analysis highlights real
advantages for the Midel filled transformer.
For more information comparing fluid filled high
fire point solutions with cast resin or dry type
transformers, please consult our transformer selection
paper ‘Transforming
Expectations' below.
As
Midel is readily biodegradable and classified
as non-water hazardous, it is used, for example
in Berlin, in locations near lakes or waterways.
MIDEL®
7131 offers high moisture tolerance in humid environments
and excellent thermal stability characteristics,
providing an ideal solution for demanding applications.
MIDEL® 7131 has been tested by an independent laboratory to ASTM D1275 B, Standard Test
Method for Corrosive Sulphur in Electrical Insulating Oils. It was found to be non-corrosive.
MIDEL® 7131 is RoHS compliant, it does not contain the flame retardants
PBB and PBDE, nor is it formulated using lead, cadmium, mercury or hexavalent chromium. The concentrations of these heavy metal contents are all below 1ppm.
For a detailed product comparison, including a comparison
of the effiency benefits of liquid filled vs dry type
transformers, please consult the comparative datasheets
below.
For more information comparing fluid filled high
fire point solutions with cast resin or dry type
transformers, please consult our transformer selection
paper 
