The Schmidt® ShortStop Deadman Control System was sold over two and
a half decades ago. It was initially intended to eliminate a specifi c cause of
inadvertent activation with electrical deadman control lines. Since its inception
and launch, ShortStop systems installed throughout the United States have
reliably provided added protection and safety to conventional electric Schmidt
deadman controls, especially in situations where deadman line shorts are more
likely.

The ShortStop PnP (Plug & Play) eff ectively provides the same type and level
of protection but in a more compact and easy-to-install package. This new
confi guration weighs less than 1.5 lbs and consists of two small enclosures that
could easily fi t or hold in one hand. In addition, the plug-and-play design can
be easily and quickly retrofi tted onto existing Schmidt blast pots with electrical
deadman controls. Installation should take only a few minutes (5 mins).

Accidental starting of the deadman control is most often caused by an electrical
short due to exposed conductors with worn insulators or a pinched electric
deadman extension cord. This system detects the short and prevents the
control system from turning on while the electrical is detected.

The logic processing of the ShortStop Control System is the electronic
proprietary control module that enables the start of the blast operation
provided no electric short is detected between the ShortStop Deadman and
the control module. Inversely, suppose an electrical short is detected between
these same two points. In that case, the module will turn off blast control,
revert to fail-safe, disable the deadman, and keep the system off until the short
is no longer detected.