Many of today’s money counters offer a counterfeit detection system that will alert you if a counterfeit bill is found. The latest counters incorporate both magnetic and ultraviolet detection systems.
Magnetic detection systems sense the magnetic characteristics of ink used in legitimate currency. If any of the currency used in the machine does not have these properties an alert will be activated. UV detection, on the other hand, can sense the UV properties that are inherent in many US bills. If the UV range isn’t correct, you will be alerted as well.