Jacobs Ranch Mine 2570W Electrical System Upgrade Presented to: - PowerPoint PPT Presentation

Jacobs Ranch Mine 2570W Electrical System Upgrade Presented to: Salt Lake City, Utah – June 2006 Presented by: Calvin Randall / Rio Tinto Energy America Aaron Spielman / Rio Tinto Energy America Rob Marnell / Drives and Controls Services Rick Scherer / Flanders Electric

Motor Comparison Table Motor MD-622M MD-822 HP @ 475 Vdc 1245 HP 1045 HP Rated Amps 2100 Amps 1760 Amps Max Operating Volts 660 Vdc 600 Vdc Peak HP @ 600 V 1875 HP 1560 HP RPM 740 RPM 740 RPM

622M Upgrade vs 622 and / or 822 Lengthened Armature and Field Iron Increased Air Flow with Larger Blower Revised Insulation System / Class H Wet Wound Welded Pole Face Bar Connections Brush Arm Rocker Ring made Adjustable V-Ring Commutator 100% Equalized on Drive End

MD-622M Benefits Higher Horse Power with Same Foot Print Cooler Running Temps ~ Longer Life at 822 Values Increased Armature Circuit Current α Torque Ease of Maintenance / Reduced Maintenance Higher RMS is not Detrimental to 836KW Generators, Case Study in Service since 1994 RTD’s in Comm Coil, Pole Face Bar, Shunt Field, optional Telemetry RTD on Armature Internal Split Connections for Ease of Maintenance Each Machine is Black Band Tested

622M vs 822 Temperature Rise Test Parameters Armature Voltage 490 Vdc Armature Current 1950 Amps Run Time 1 Hour Torque 9050 Ft Lbs RPM 743 RPM HP 1281 HP 622M Field Voltage 93 Volts 822 Field Voltage 67 Volts

Temperature Test Results Degrees Celsius MD-622M MD-822 Commutator 117 134 Armature 148 158 Comm Coil 70 82 PF Bars 97 126 Shunt Fields * 115 94 Intake / Exhaust 30 / 46 30 / 48 * 622M Served as Generator at Higher Field Amps * 822 Served as Motor at Lower Field Amps

Questions ? Thank You