Qualitrol 509ITM Series, Руководство пользователя

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Exponent
(4 fields) Allows you to enter the exponent parameter used in the temperature
calculation for each of the four Cooling Modes. The exponent describes
the “rise” curve of the winding temperature above the oil temperature.
When installing a 509ITM on older transformers, this information might
be difficult to obtain. In those cases, Qualitrol recommends:
•
For ONAN (natural convection): 1.6
•
For ONAF (natural convection; forced air
−
fans only): 1.6
•
For OFAF (forced oil; forced air
−
fans and pumps): 1.8
•
For ODAF (directed forced oil and forced air): 2.0
Winding Time
Constant
(4 fields) Allows you to enter a time constant for each of the four cooling modes.
The time constant is defined as the time required to reach 63.2% of the
final winding temperature rise for a specific load increase. The winding
temperature reaches its final value for a given load in approximately five
time constants.
Note:
You can program the 509ITM for up to four cooling modes, including natural
convection. If there are less than four cooling modes, the unused rows should match
the last configured row.
Do not enter zeroes as a value .
TransLife
TM
This section of the Advanced CT Temperature Scaling Setup window includes the
parameters that are required if you want to use the Critical Forecast section of the
TransLife
TM
Setup. If you are not using the Critical Forecast feature, leave these parameters
at the default values.
The fields in this section are described below.
Oil Rise
(4 fields) Allows you to set the temperature rise value of the oil of the transformer
at nominal load. This is derived from the Transformer Heat Run Report
by taking the Oil Rise Temperature over ambient at nominal load and
subtracting the Ambient Test Temperature.