Document number 165-31591 Revision K Page 7 of 63

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2 SUMMARY OF SPECIFICATIONS MODEL 7838 EDDY CURRENT BRAKE

2.1 Specifications

General Specifications Principal of Operation Induced Eddy Current Braking Torque-Maximum @ 150 RPM, lb-ft (n-m) 117,000 (158,631) Torque @ 50 RPM, lb-ft (n-m) 96,000 (130,159) Number of Magnets 2 Number of Coils per Magnet 2

Coil Internal Resistance @ 68 F (20 C), Ohms 13.4-13.9 11.0-11.5 (Prior to July 1985)

Total Brake Input Resistance @ 68 F (20 C), Ohms 3.9-4.1 2.8-2.9 (Prior to July 1985) Brake Excitation

Voltage, volts DC 250

Current-Coil Temperature @ 68 F (20 C), Amps DC 74.07 89.29 (Prior to July 1985)

Power Input @ 68 F (20 C), kW 18.5 22.3 (Prior to July 1985) Cooling Water Requirements

Flow @ 100 F (38 Deg. C) At Brake Inlet, gpm (lpm) 150 (568) pH 7.0-7.5 Maximum Discharge Temperature, oF (o 165 (74) C)

Cooling Water Piping Inlet (2) 2 NPT Outlet (2) 4 NPT Overflow (2) 1 NPT

Overall Sizes Height, in (mm) 78 (1,981) Width, in (mm) 38 (965) Weight, lbs (kg) 28,000 (12,701) Inertia (WK2)-Shaft and Rotor, lb-ft2 (kg-cm2 37,938 (15,987,118) ) Weight-Shaft and Rotor, lbs (kg) 6,458 (2,929) Shaft Size (Oilfield Standard)

Diameter, in (mm) 7.5 (190.5) Taper per foot, in (mm) 1 (31.75)

Average Rotor Radial Clearance (Air Gap) Over Magnets (Without Paint or Other Build up), in (mm) 0.055-0.065 (1.397-1.651)

Maximum RPM 600