Qualitrol 509ITM Series, Руководство пользователя

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Condition 3: Hydrogen exceeding specified levels should prompt additional investigation.
Immediate action should be taken to establish a trend. Fault(s) are probably present. For
hydrogen levels of 701
– 1800 PPM.
Condition 4: Continued operation could result in failure of the transformer. Proceed
immediately and with caution. For hydrogen levels > 1801 PPM.
The IEC 60599:1999 Standard states an increase in gas concentrations of more than 10%
per month above typical concentration values is generally considered a prerequisite for
pronouncing the fault as active. Much higher rates of gas increase, such as 50% per week,
and/or evolving towards faults of higher energy are generally considered serious, especially
if they exceed alarm concentration values.
Ranges of 90% typical concentration values observed in power transformers (all types); for
no OLTC the hydrogen range is 60
– 150 PPM; for communication OLTC (those
transformers that share oil with the LTC) the hydrogen range is 75
– 150 PPM.
Typical rates of gas increase for power transformers for hydrogen is <5 PPM per day.