The invention discloses a rheostat
structure based on an electro-hydraulic
starter rheostat. The rheostat structure comprises a water tank, three pairs of
electrode bars inserted into the water tank and an
electrode bar lifting structure capable of changing
water resistance. A standby water tank, locating columns, a float, a magnetic material arranged on the float and a reed
pipe are further included, the standby water tank is arranged adjacent to the water tank, the water tank and the adjacent water tank are separated only through a common plate, a water pump is arranged in the standby water tank, and the water pump can inject water of the standby water tank into the water tank through an inlet in the upper portion of the water tank. The locating columns are fixed in the water tank. The locating columns are sleeved with the float, and the float can vertically move along the
water level. The reed
pipe is arranged in a sealing
pipe of the non-magnetic-conducting material. When the
water level of the water tank is reduced, the reed pipe is triggered by the magnetic material to be closed, and the water pump works. A water tank cover is provided with holes allowing the
electrode bars to be inserted, sealing rings and housings fixing the sealing rings on the inner face of the water tank cover, and the electrode bars are sleeved with the sealing rings. The rheostat structure has the advantages of reducing the temperature of the water tank, automatically adding water, preventing water losses, and prolonging the maintenance period.