Developed specifically to provide a current sense device with high current-carrying capability for power electronics circuits, the TT Electronics OARS-XP Series metal element resistors from TT electronics IRC deliver power ratings up to 5 watts in a unique, flameproof open-air surface mount form factor that offers the maximum heat dissipation for a PC board mounted component.
The OARS-XP Series resistors consist of a 0.25” wide metal element resistance alloy, welded to compliant copper terminals designed to handle TCE (thermal coefficient of expansion) mismatch between the device and the PC board. Unlike other resistor technologies, such as thin film, thick film or foil devices, the open air metal element will not experience degradation of performance at extreme temperatures, even up to 500°C (a conservative temperature rating for the alloy itself). However, since most PCB solder materials typically melt between 183°C and 230°C, the solder will reflow long before the device itself experiences any heat damage.