Power Transformer Fault Severity Estimation Based on Dissolved Gas Analysis and Energy of Fault Formation Technique

Table 4

IEEE DGA limits [2].

Evolved gas	Normal limits (acceptable) (ppm)	Extreme limits (unacceptable) (ppm)
Hydrogen	<100	>1800
Methane	<120	>1000
Acetylene	<1	>35
Ethylene	<50	>200
Ethane	<65	>150
Carbon monoxide	<350	>1400
Carbon dioxide	<2500	>10 000