Description of any water firefighting systems for transformer do not have a lot of difference between them.
The difference is only in the beauty of design. The main principle of operation of all systems — the use of water.
But all standard systems have serious flaws that reduce the effectiveness of systems to zero.
The main principal disadvantages:
Fighting a transformer oil fire is not much different than fighting a crude oil fire with nothing but water — that’s why foam is used to prevent spreading one.
Quote from Minerals oil SDS sheet: “5. Fire-fighting measures
Suitable extinguishing media — Water fog. Foam. Dry chemical powder. Carbon dioxide (CO2).
Unsuitable extinguishing media — Do not use water jet as an extinguisher, as this will spread the fire.”
Transformer oil explosion after start water deluge firefighting system.
Three reasons for the explosion:
1. Use water only.
2. Most of the delay system startup.
3. The use of water contaminated by rust.
The dielectric strength of materials is their ability to resist voltage and act as an insulator compared to air as a standard. The air standard is 1.0, water about 80. Spraying clean water on high voltage insulators from a newly constructed system for demonstration purposes is not much different than rain water. The more low dielectric contaminants in the firewater, the lower its dielectric strength will be. Below is an example of rusty water being drained from a fire pump sitting for several months of not running. The iron content would sharply reduce this water’s dielectric strength, risking an insulator flash-over to the transformer’s grounded case.
Advantages of ISAS against a standard system.
1. The system ISAS has no long black iron pipes,
— Not water tanks of black iron
— It has no iron pumps
2. The system ISAS uses only pure water level of rainwater without any iron compounds.
ISAS system uses a mixture of clean water and foam.
3. The system of ISAS has zero inertia. Start time 2 seconds.
4. ISAS system has no pump, pipes and special tanks.
These four positions indicate that the system ISAS several times more efficient in several times cheaper than any other stationary system.