Comparing with PT

CVT has many merits.For example

CVT doesn’t occur ferromagnetic resonance with external elements

has simple structure and enough insulation excess

but CVT’s faults ratio is still high.Capacitors damped and ca- pacitor cake breakdown are familiar faults of CVT.But affairs of the oil tank overheating often occur because of middle elec- tromagnetic units various faults.The paper introduced and analyzed the process and reasons of some fuel tank overheating in- cidents

and point out that

the overheating of the protection resistance and damping resistance by long-term earring current

which caused by internal and external faults of the electromagnetic units

are the main reason of the oil tank overheating.