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A dual hydraulic jack system for more quickly raising the jack up to a load to be lifted. The dual hydraulic jack system includes a dual pump assembly mounted a base. The dual pump assembly comprises an inner piston assembly movably positioned in a first fluid chamber and an outer piston assembly mo

A dual hydraulic jack system for more quickly raising the jack up to a load to be lifted. The dual hydraulic jack system includes a dual pump assembly mounted a base. The dual pump assembly comprises an inner piston assembly movably positioned in a first fluid chamber and an outer piston assembly movably positioned in a second fluid chamber. A jack assembly is provided for lifting a load. The jack assembly includes a jack piston assembly movably positioned in a third fluid chamber. A first fluid channel is provided for fluid communication between the first, second and third fluid chambers. A second fluid channel is provided for fluid communication between a reservoir and the first and second fluid chambers. A first conduit is provided for fluid communication between the reservoir and the third fluid chamber. A plurality of valves is provided for controlling unidirectional flow of the fluid through the first and second fluid channels.

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A dual hydraulic jack system for more quickly raising the jack up to a load to be lifted. The dual hydraulic jack system includes a dual pump assembly mounted a base. The dual pump assembly comprises an inner piston assembly movably positioned in a first fluid chamber and an outer piston assembly mo

A dual hydraulic jack system for more quickly raising the jack up to a load to be lifted. The dual hydraulic jack system includes a dual pump assembly mounted a base. The dual pump assembly comprises an inner piston assembly movably positioned in a first fluid chamber and an outer piston assembly movably positioned in a second fluid chamber. A jack assembly is provided for lifting a load. The jack assembly includes a jack piston assembly movably positioned in a third fluid chamber. A first fluid channel is provided for fluid communication between the first, second and third fluid chambers. A second fluid channel is provided for fluid communication between a reservoir and the first and second fluid chambers. A first conduit is provided for fluid communication between the reservoir and the third fluid chamber. A plurality of valves is provided for controlling unidirectional flow of the fluid through the first and second fluid channels. signal levels, which allows for lower cost construction and lower power operation. s coupled to said digital output. 3. The device of claim 2, wherein said microcontroller biases said digital output to first and second states, and said first state corresponds to said given DC potential and said second state corresponds to said reference DC potential. 4. The device of claim 3, wherein said given DC potential is approximately 5 volts. 5. The device of claim 3, wherein said reference DC potential is approximately equivalent to ground. 6. The device of claim 1, wherein said driving circuit comprises at least one capacitive device. 7. The device of claim 6, wherein said driving circuit further comprises at least one resistive device. 8. The device of claim 7, wherein said microcontroller comprises an analog input coupled between said resistive device and capacitive device for measuring said voltage associated with said level of said fluid to be sensed. 9. The device of claim 1, wherein said given DC potential is greater than said reference DC potential. 10. The device of claim 1, further comprising a driving circuit serially coupled between said probe and said microcontroller. 11. The device of claim 1, further comprising a plurality of memory locations accessible by said microcontroller and for storing data for comparing against said measured voltage. 12. The device of claim 1, wherein said plurality of instructions is stored in a plurality of memory locations. 13. A fluid level sensing device comprising: a computing processor; a probe; a plurality of memory locations being accessible by said processor and storing a plurality of instructions operable to pulse said probe with a given DC potential and measure a voltage associated with a fluid level to be sensed at predetermined times with respect to said pulsing; an output controlled by said processor to achieve first and second states; a resistive device; and, a capacitive device; wherein said resistive and capacitive devices are coupled in series between said output and said probe, and said voltage to be measured is associated with said capacitive device and is responsive to said pulsing. 14. The device of claim 13, further comprising an analog input coupled to said processor and to a common node between said resistive device and capacitive device for receiving said voltage to be measured. 15. A method for operating a fluid level sensor comprising a microcontroller including an analog input and a digital output, and a probe coupled to said microcontroller, said method comprising: activating said digital output thereby applying a given DC potential to said probe; measuring a voltage indicative of said fluid level to be sensed using said analog input; and, deactivating said digital output thereby applying a reference DC potential to said probe. 16. The method of claim 15, wherein said activating said digital output causes a buildup of said voltage indicative of said fluid level to be sensed. 17. The method of claim 16, wherein said deactivating said digital output causes said built-up voltage indicative of said fluid level to be sensed to diminish. 18. The method of claim 17, further comprising comparing said measured voltage to at least one predetermined value. 19. The method of claim 15, further comprising selectively activating at least one relay dependently upon said comparing. vided on an electric insulating board is made of a silver alloy including glass. Preferably, the contact member sliding on the electrodes is made of a gold alloy consisting of 99% by weight of gold and 1% by weight of cobalt, so that an anti-sulfurization and an abrasion resistance between the contact member and the electrodes is ensured. However, the weight percent of gold and other alloys may vary depending upon the abrasion characteristics desired.