3 phase problem after spark did 5 year safety inspection

[MJPD29]

There have been several reports of Hager RCCBs detonating when the test button is pushed which then blows the cutout fuse, it also happened to me a few years back, really loud.

Had it happen with a square d rcbo once. All further test buttons were pressed with eyes closed and touching cloth.

 

[jimthegent]

Had it happen with a square d rcbo once. All further test buttons were pressed with eyes closed and touching cloth.

Further to all that we had surge protection fitted but it still managed to turn pdu into molten plastic and circuit boards in scrap would surge protection be useless in this situation