The remit from the customer was to replace an aging DC system with an up to date AC Inverter drive system. The main issue was to keep the size to a minimum but to include as many features as we could into the design. As the project developed we included digital readout for speed and time with manual or auto control so the user can set the speed for the mixer and how long the mixer runs for. We have incorporated a Control Techniques Unidrive M drive into the system and have utilised the on board PLC and the industry standard Codesys programming environment to create the required control program.
This has all been fitted into a stainless steel enclosure with miniscule dimenions of 200 x 200 x 120mm. We also have included pushbuttons for starting and stopping as well as raise and lower lift controls. Potentiometers mounted on the enclosure provide inputs for speed and time. We came up with an ingenious method to mount the inverter so that there are no unsightly screws or nuts protruding from the enclosure.