Abstract: An apparatus for indicating the time integral of the electrical power consumed in elastomer mixing, working, warming or other processing and for controlling the processing in accordance therewith. An electrical signal, derived from the electrical power consumed by an electrical motor driven elastomer processing apparatus, is compensated for no-load operation of the apparatus and then continuously integrated with respect to time to provide an output which is employed to produce a digital read-out of the energy consumed in the processing with control of the processing being effected in accordance therewith.