Sandvik 887 501 29 Push Button Kit

The push button kit, part 887 501 29, is the operator's contact point with the machine's control circuit, and it is supplied as a kit because the button head, its contact block, and the sealing boot only work properly as a matched set. The button is pressed hundreds of times a shift, often with gloved hands and in dust, so the part that fails first is rarely the plastic head but the small contacts behind it.

A button that has to be pressed twice, sticks down, or gives an intermittent signal is usually showing worn or contaminated contacts, or a boot that has split and let water and fines in. Replacing the kit as a whole restores the original contact travel and the seal around it, instead of fitting a new head onto a contact block that is already pitted. Because a control button may sit in a start or stop function, it is worth confirming the part number against the one being replaced before the circuit is closed up again. Stalroc quotes this Sandvik reference by part number and exports worldwide to mining, quarrying, and drilling contractors.