Schweitzer Engineering Laboratories SEL-749M - Page 13

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Date Code 20080918 Instruction Manual SEL-749M Relay
List of Figures
Figure F.1 Motor Thermal Limit Characteristic Plotted With Motor Starting Current ............................................ F.3
Figure F.2 Electrical Analog of a Thermal System ................................................................................. F.3
Figure F.3 Typical Induction Motor Current, Torque, and Rotor Resistance versus Slip........................ F.4
Figure F.4 Motor Starting Thermal Element ........................................................................................... F.6
Figure F.5 Motor Running Thermal Element With Resistance and Trip Level Undefined ..................... F.7
Figure F.6 Calculating the Normal Operating Energy by Using Locked Rotor Trip Times.................... F.7
Figure F.7 Motor Running Thermal Element ..........................................................................................F.8
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