Bimetal temperature switch replacement on inverter arc welder machine

[nuno]

Hello all,

I have an inverter arc welder which turns on but once starting to weld it won't push current/enough current out. In a 1st glance, there's a BR-B2D 85ºC thermal switch stuck open, I guess that could be the sole reason (already checked output connectors and such for deficient electrical connections). Problem is I can't find a replacement except in alibaba at a 1000 MOQ (https://rtsensor.en.alibaba.com/product/60499753078-803502219/BR_B2D_50C_AC_Bimetal_Thermal_Protector_250V_5A_With_Snap_Action_Disc.html - proper datasheet not found) . On ebay there's lots of KSD9700 series on sale (https://www.nikom.biz/pdf/KSD-9700.pdf), and the only difference I can see is that the hysteresis is a little different, with the KSD closing again at 60ºC+- 15ºC instead of the 55ºC+-15ºC of the original BR-B2D. Would you do the swap? Or would it be safer to use the 80ºC version (at the expense of a maybe a little less inverter working time), which closes again at 55ºC+-15ºC as the BR-B2D? I don't know if this device acts regularly during normal use (no experience with welding nor welding machines) although I suspect it does since the device is self-resets (otherwise I guess they would save some cents and use a thermal fuse).

Any comments are appreciated... thanks!