An electrical stability testing device includes a cup configured to receive a fluid sample. The testing device also includes a pair of electrodes positioned at least partially within the cup. The electrodes are spaced apart from one another by a predetermined gap. The electrodes are configured to have the fluid sample positioned within the predetermined gap while performing an ES test on the fluid sample in the cup. The testing device also includes a wiper positioned at least partially within the cup. The wiper is configured to pass between the electrodes after the ES test has concluded. A width of the wiper is greater than the predetermined gap between the electrodes. The wiper is configured to deform as the wiper passes through the predetermined gap such that the width becomes substantially equal to the predetermined gap and sides of the wiper contact ends of the electrodes to clean the electrodes.