Electromechanical Voltage Regulator Older voltage regulators use contact points that are operated by electromagnetic coils. These were called electromechanical voltage requlators Electronic Voltage Regulator(EVR) All vehicles made within the last 15 years use an electronic voltage regulator. The electronic voltage regulator uses power transistors, integrated circuits, diodes, and other solid state parts to control alternator output. the electronic voltage regulator eliminates contact points and moving parts that can stick, oxidize, or wear. Some electronic regulators are remotely mounted. However, electronic voltage regulators are reliable, durable, and small enough to be incorporated into the alternator itselfElectromechanical Voltage Regulator Older voltage regulators use contact points that are operated by electromagnetic coils. These were called electromechanical voltage regulators. Electronic Voltage Regulator(EVR) All vehicles made within the last 15 years use an electronic voltage regulator. The electronic voltage regulator uses power transistors, integrated circuits, diodes, and other solid state parts to control alternator output. The electronic voltage regulator eliminates contact points and moving parts that can stick, oxidize, or wear. Some electronic regulators are remotely mounted. However, electronic voltage regulators are reliable, durable, and small enough to be incorporated into the alternator itself