Surge-rated resistors are electronic components designed to withstand and dissipate high voltage surges or spikes that can occur in various electrical systems, protecting other components from damage. These resistors are commonly used in surge protection devices, as they can absorb and discharge large amounts of energy quickly and efficiently, preventing damage to the circuit. Surge-rated resistors are typically characterized by their surge voltage rating, power rating, and impedance waveform handling capability, which determine their suitability for specific applications. In recent years, film resistors have emerged as a viable replacement for traditional carbon composition resistors in high-voltage surge protection applications, offering improved electrical and environmental stability, better tolerance and temperature coefficient, and better long-term availability.
“For applications with high voltage surge and low energy requirements, they are a viable replacement for carbon composition resistors, providing improved electrical and environmental stability, better tolerance and temperature coefficient, with better long-term availability,” according to the company.
The range of values covers 560kO through 12MO The 10kV surge-rated resistors can be found in the Stackpole’s ASRM12 (nominally 500mW), ASR1 (1W), ASRM1 (1W) and ASRM2 (2W) series.
Values ranging from 3.3O to 510kO within similar series have been also rated in 5KV electric surges.
In all cases the test is the discharge of a capacitor of 10nF. The data sheet explains the single and repetitive pulse power handling in depth for a variety of impedance waveforms.
The company is anticipating high-voltage applications for appliances for domestic use, air conditioning as well as metering, automation, in medical and other devices. “Surge protection devices typically require resistors with high working voltage that may be challenging to find,” it stated. “If the applications are low current or low energy, film resistors are an ideal technology.”