ABB Relion REG670, Applications Manual

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• Average : The average of all phase currents of winding is considered for
calculation.
• Maximum : The maximum current out of the all phase currents is considered for
calculation.
TempeUnitMode : This setting is used to select the temperature unit to be used for the
function interface. The options are:
• °F : The temperature unit will be selected as °F. Since all calculation formulae
needs temperature values in °C, the temperature inputs are converted into °C for
calculation. Once the calculations are done, the outputs in °C are converted into
°F.
• °C : The temperature unit will be selected as °C. All temperature inputs will be
taken as they are and the output is given in °C.
LOLSPTR can work with (n-1) winding CT availability, that is, if the given
transformer has three windings and it has CTs only in two windings, then the function
will calculate the missing winding current based on voltage transformation ratio.
Following settings are required to calculate the winding current with available CT
input:
AvailableCT : Availability of CT connection can be set by this setting. The options are:
• Winding 1 : Only winding 1 CT is available. This option can be selected when two
winding transformer is considered.
• Winding 2 : Only winding 2 CT is available. This option can be selected when two
winding transformer is considered.
• Winding 1&2 : Only winding 1 and winding 2 CTs are available. This option can
be selected when three winding transformer is considered.
• Winding 1&3 : Only winding 1 and winding 3 CTs are available. This option can
be selected when three winding transformer is considered.
• Winding 2&3 : Only winding 2 and winding 3 CTs are available. This option can
be selected when three winding transformer is considered.
• All windings : All windings CTs are available. This option can be selected for both
two and three winding transformer.
RatedVoltW1 : This setting is used to set the rated voltage of winding 1 in kV.
RatedVoltW2 : This setting is used to set the rated voltage of winding 2 in kV.
RatedVoltW3 : This setting is used to set the rated voltage of winding 3 in kV.
UPerTap : This setting is used to set the voltage increment/decrement between two
successive tap positions (ΔV) in kV.
Time required for the top oil temperature in relation to ambient temperature to reach
its ultimate value is a function of the thermal oil time constant. The function has the
following settings related to oil time constant.
1MRK 502 071-UEN -
Section 17
Monitoring
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062 659
Application manual