Stud welding units INTRA 2100/1400 Operating manual 07.2021 / EN Date: Rev.: July 2021 A 8 Repairs H8 H2 H3 H4 H18 F2 Page 58 F1 X4 H5 X3 F3 F1 – F3: Fuse elements X1 – X4: Plug connection H2 – H18: Diagnostic LEDs H7 X2 H9- X1 H14 Internal control card (example ...