Schweitzer Engineering Laboratories SEL-701-1, Инструкция по эксплуатации

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SEL-701-1 Monitor
Date Code 20011009
Settings Calculation
RTD-Based Protection
3.34
Temperature settings. Two winding RTDs must indicate excessive temperature when
the Enable Winding Trip Voting setting equals Y. Only one excessive temperature
indication is required if Winding Trip Voting is not enabled. Bearing Trip Voting works
similarly.
The alarm and trip temperature settings for Bearing, Ambient, and Other RTD
types function similarly except that trip voting is not available for Ambient and Other
RTDs. There is one trip temperature setpoint and three alarm temperature setpoints for
each RTD.
To disable any of the temperature alarm or trip functions, set the appropriate
temperature setting to OFF.
Only healthy RTDs can contribute temperatures to the alarm and trip functions.
The monitor includes specific logic to indicate if RTD, leads are shorted or open.
When you have connected an ambient temperature sensing RTD and set trip
temperatures for one or more winding RTDs, the monitor gives you the option to
enable RTD thermal model biasing. When you enable RTD biasing, the monitor:
Calculates RTD % Thermal Capacity and adds the value to the
Thermal Meter values.
Automatically reduces the winding RTD trip temperatures and
thermal element trip threshold if ambient temperature rises above
40°C.
Provides an RTD Bias Alarm if the winding temperature exceeds
60°C rise over ambient and the RTD % Thermal Capacity exceeds the
thermal element % Thermal Capacity by more than 10%.