On a potato and beet washing machine the motor is selected according to whether the machine has a drum, brushes or a tank, and how much product, soil and water it carries. Power and speed are first taken from the machine nameplate or the old motor's label; water splash, mud and starting with the machine full are then assessed.

DRG-90S-2 1.5 kW 3000 rpm cast iron frame DRG three-phase motor – potato washing machine motor

Drive arrangement by machine type

  • Rotating drum: Turns slowly and is usually driven through a gearbox. Starting a drum full of product is heavy. DRG does not sell gearboxes; the input flange and shaft bore of the existing gearbox must match the motor to be selected.
  • Brush washer: Several brush shafts are turned by one motor through a chain or belt; the load changes as the brushes wear or jam with product.
  • Tank washer: The water pump and discharge elevator run on separate motors; each is chosen for its own load.

Soil, stones and start-of-season load

Beet and potatoes arrive from the field with plenty of soil and the odd stone. When the harvest runs through wet weather the share of mud rises and the drum and brushes turn harder. A stone can wedge between the drum and the frame and lock the machine. Motor power should therefore be considered not just with clean product but with the dirtiest batch of the season, and the destoning arrangement must be confirmed to work.

Water, mud and motor position

IP55 protects against water jets, not against the motor being submerged. The motor should sit above the tank level, where mud splash cannot reach it directly. A fan cover clogged with mud cuts off cooling. Placing the terminal box with its cable entry facing downwards makes it harder for water to run along the cable into the box.

Information required when ordering

  1. Drive type: gearbox, chain, belt or coupling
  2. If a gearbox is used, its input flange and shaft size
  3. Product throughput per hour and daily running time in season
  4. The motor's position relative to water and mud

For similar machines see the vegetable and fruit washing machine motors page; for geared drives you can compare motors suitable for gearboxes with the options in the shop.