WarP ™Motors for electric vehicles - when power and quality matters!

Our motors are manufactured and warrantied by Warfield Electric Co. in Frankfort, Illinois USA. Warfield is the nation's largest rebuilder of series wound DC motors. Warfield also manufactures new motors to our specifications. From their years of experience repairing "all the other brands of motors" they know the common failure points. From that starting point it was a matter of Warfield working with us to help design motors that are intended for the unusual stresses encountered in electric and hybrid electric vehicles.

EVers are always looking for information that is not normally provided by motor manufacturers. Industry wide, motors are rated by operating temperature. All our motors are utilize better than Class "H" insulation. Class "H" insulation is rated at 180 degrees Celsius.

All our motors are equipped with an internal "Temperature Snap Switch." This is a normally closed temperature switch, set at 150 degrees C. This switch will open if the motor starts to overheat. This switch can be connected to a diagnostic system or an emergency shut off switch ... or not connected to anything. All of our motors now include brush wear sensors as well.

NOTE: The hottest point on the exterior of a motor should never exceed 180 degrees Celsius, although our motors are stress tested to 205 degrees C. The maximum brush temperature should not exceed 205 degrees Celsius.

For vehicles intended solely for use on the drag strip, motor cooling is not required. The motors do not run long enough to build any substantial amounts of heat. HOWEVER -- fans are still required. When a brushed, series wound DC motor runs -- it grinds down the brushes. As a result, a cloud of carbon dust is circulated inside the motor. If this dust accumulates, it is possible to have an arc flash over inside the motor -- causing serious damage. The carbon dust must be blown out of the motor. If the motor is being used for racing purposes we recommend the carbon dust be blown out after each pass or event.

Some customers have asked for motor ratings while cooling the motors. We do not have a horse power rating for a motor with forced air cooling. There are some obvious limitations to forced air testing, such as ambient temperature, fan type, fan efficiency, motor intake & exhaust ports and CFM (cubic feet of air per minute) moved by the fan.

We have performed some testing with forced air ... and cooling with exotic gases, such as CO2, helium and argon. What we have found is interesting. For EVer's, ambient temperature is the key. As a motor gets hot, the HP is lower than the initial HP generated by a cool motor. By blowing enough air to maintain, or approximate, ambient temperature ... the motor's one hour HP rating can be maintained to near its initial HP output. This is not something normally tested or rated by motor manufacturers ... but typically you can expect a 10 - 15 % increase in HP, with 20% possible on some motor designs.

One of the problems in determining motor ratings (for EVers) is finding a dynamometer capable of handling the unusual voltage and current used in racing EV's and the torque developed in testing these motors. So far, we have been unable to locate such a dyno ... but we are still looking and have recently developed some good prospects. To date, most of the high voltage ratings seen on our web site have been calculated using standard industry formulas and practices.

Extrapolations with various voltages are quite simple - usually doubling the voltage will approximately double the RPM of the motor. Extrapolating increased amperage is quite a bit more difficult. Limited data is available on a special request basis that illustrates up to 1400 Amps and 170 volts to a WarP 13 motor. Our motors have all been dyno tested on the Warfield Electric dynamometer. This dyno is capable of 72 Volts and 450 Amps. We supply graphs that approximate the actual dynamometer points accumulated for each of our motors.

WarP ™Motors do not have interpoles. The interior size limitations of the motor case prevent interpoles from fitting inside the 8 and 9 inch motors. That is why no motor (of these HP ratings) is available with interpoles in a 9" or smaller configuration. Our 11", and 13" motors, and potentially larger motors, may be equipped with interpoles. The exact configuration of the interpoles may be specified. Interpoles that are incorrectly engineered may cause substantial performance problems. There are additional costs associated with the addition of interpoles.We have also strived to improve the performance of our motors by incorporating series/parallel field switching as a standard item on our 13" motors. We intend to consider this an option on our other motors as well.

Our TransWarP ™Motors are unique to the industry. They are the only motors that provide a drive end shaft of 1.370 inches, with a 32-tooth spline that matches the output of a Turbo 400 transmission. This makes these motors ideal candidates for direct drive applications. We even made the commutator end shafts identical to the drive end shafts of the normal WarP ™Motors to ease the task of joining two motors together. TransWarP ™Motors are currently available in 7.25", 9.25" and 11.45" diameter motors.