The electric service load of a machine having at least one electric heater and at least one electric motor may be managed as follows. The interior surface encloses a volume that tapers outwardly in a downward direction so that any horizontal cross-section of the volume fits inside each horizontal cross-section below it from a full to an empty level of the dispenser. Probe holders are mounted on the circuit boards to support measurement probes with the probing contacts of the measurement probes coupled to the signal launch contacts. The button can have either a snap fit or a threaded connection to the plunger.