The ROV device's high current-handling and energy absorption capability, fast response, and low cost can make it suitable for use in line voltage applications.
ROV Metal Oxide Varistors Raychem
"ROV metal oxide varistors help protect power systems from damage caused by transient overvoltage faults such as lightning, power contact, and power induction. Suitable for a broad range of applications, ROV devices help protect sensitive electronic equipment from potential power surge damage by clamping high-energy, short-duration impluses."
"An ROV device is a varistor fabricated using a Zinc Oxide (ZnO) powder, sintered with other metal oxide ceramics. The resulting structure is a polycrystalline ceramic that consists of distributed ZnO grains, separated by other metal oxide ceramics."
Raychem Circuit Protection Products
"A varistor is a variable resistor-a voltage dependent, non-linear device whose resistance decreases as the voltage applied across the device increases. "
ROVs can also be used to help protect electrical equipment from damage caused by large voltage or power transients on the AC Mains inputs. In a coordinated circuit protection scheme the ROV can be paired with a PolySwitch overcurrent protection device to help improve equipment reliability and fulfill IEC-61000 test requirements.
CKE is a line of high voltage and high power silicon rectifiers, MOVs, selenium suppressors, silicon carbide varistors, and assemblies. These products are appropriate for a wide range of applications, and find a special fit in the power generation, resistance welding and RF power systems markets.
It consists of a 34mm square format varistor element ( MOV) with an integral thermally activated element designed to open in the event of overheating due to abnormal over-voltage, limited current conditions as outlined in UL1449. - https://www.littelfuse.com/
TMOV34S Thermally Protected Varistor - Littelfuse
The device has a third lead, an indicator lead, which may be used to indicate that the MOV has been disconnected from the circuit.
The integrated configuration also offers lower inductance than most discreet solutions resulting in improved clamping performance to fast over voltage transients.
"Switching power supplies are power supplies switched by high-speed semiconductor switches. They are the most common type of compact, lightweight, high-efficiency power supply. Uninterruptible power systems (UPS) are backup power supplies that use a built-in battery to stably supply continuous clean power to connected devices when the regular supply power shuts down due to a power failure or other power problem. TDK-Lambda offers both these types of power supplies".