ABB REC670 Applications Manual page 560

Section 17
Monitoring
554
TankMass: This setting is used to set the transformer tank mass. This mass is only the
tank and fittings that are in contact with heated oil.
LoadLoss: This setting is used to set the transformer load loss at rated condition.
TTLoadLoss: This setting is used to set the transformer load loss arrived from type test.
NoloadLoss: This setting is used to set the transformer no-load loss.
TTNoloadLoss: This setting is used to set the transformer no-load loss arrived from
type test.
Winding time constant is the time for winding temperature to rise over the oil
temperature to reach 63.2% of the difference between the final rise and initial rise
during a load change. The winding time constant may be estimated from the resistance
cooling curve during thermal tests or calculated by the manufacturer using mass of the
conductor material. The function has the following settings related to winding time
constant.
WdgTmConstMode: This setting is used to select the winding time constant mode of
input to the function. It has three options:
• Standard: Winding time constant is taken from the IEEE or IEC standard as
selected for the temperature calculations.
• User defined: Winding time constant is provided by the user through setting. The
value may be given by the transformer manufacturer.
• Calculated: Winding time constant is calculated by the function based on the
transformer parameters given by the user.
WdgTimeConst1: This setting is used to get the winding time constant for winding 1.
This is used when the WdgTmConstMode setting is selected as User defined.
WdgTimeConst2: This setting is used to get the winding time constant for winding 2.
This is used when the WdgTmConstMode setting is selected as User defined.
WdgTimeConst3: This setting is used to get the winding time constant for winding 3.
This is used when the WdgTmConstMode setting is selected as User defined.
The winding time constant is likely to be in the order of 5 to 20 minutes.
ConductorType: This setting is used to select the winding material between copper and
aluminum. This setting is useful when setting WdgTmConstMode is selected for
calculation. This setting has two options:
• Copper: Winding material is selected as copper.
• Aluminum: Winding material is selected as aluminum.
1MRK 511 401-UUS A
GUID-BDD32D22-D1C2-47C2-9B4C-A055C847CCA2 v1
Bay control REC670 2.2 ANSI
Application manual