The Sawstop Safety System - SawStop CB31230 Owner's Manual

The SawStop Safety System

This table saw is equipped with the SawStop
reduce the potential for a serious injury in the event of accidental contact with the saw blade. SawStop
are the first saws ever built to be smart enough to know the difference between you and the wood you are cutting.
The SawStop
two components, an electronic detection
unit and a fast-acting brake. The electronic
detection unit detects when a person contacts
the blade. A small electrical signal is induced
onto the blade by electrodes placed around
the arbor. Although this low voltage, high
frequency signal is too small to feel, it can
be measured by the detection system. When
human skin comes into contact with the blade
(or arbor), a portion of the signal is absorbed
by the body due to the inherent electrical
capacitance of the human body. As a result,
the signal on the blade gets smaller and the
detection unit recognizes this as contact.
Wood and
materials such as plastic, foam, cardboard,
®
Corian , melamine, etc., do not cause a drop
in the signal because those materials do not
absorb the signal on the blade. Conductive
materials such as aluminum and other metals,
carbon fiber materials, mirrored acrylic, carbon-filled materials, etc., will typically cause the brake to activate. If you
need to cut these conductive materials, the safety system can be placed in "Bypass" mode to temporarily disable
the brake. (The Bypass mode is discussed on page 33.)
The fast-acting brake includes a small fuse that holds a strong spring in compression. If the electronic detection
unit detects contact while the blade is spinning (including during coast down), the fuse is burned by a surge of
electrical current. The spring then pushes an aluminum brake into the teeth of the spinning blade. The teeth cut into
the brake, stopping the blade. The total time between the detection of contact and stopping the blade is just a few
milliseconds. If the brake is activated while the blade is at or near full speed, the blade will also quickly retract below
the table. The system will not activate the brake when the blade is stopped–even if you spin the blade by hand. This
allows you to touch or change the blade when the motor is off just as with ordinary table saws. However, for safety,
always switch the Main Power and Disconnect switches to OFF when changing the blade.
The SawStop
many different self-checks to ensure that the components of the system are operating properly. If any problems are
detected, the safety system will disable the motor and display a system status code to identify the problem (see
page 30 for a description of the system status codes and the corrective action). If the problem is detected while the
motor is spinning, the motor will be shut off. The safety system will not allow the motor to be started, even in Bypass
mode, as long as a problem is detected.
The electronic detection unit and fast-acting brake are contained in the "brake cartridge," which is positioned
under the table and just behind the blade (see Fig. 1). The brake cartridge must be correctly installed before the
motor can be started (see page 40 for instructions on removing/installing the brake cartridge). In the event that the
brake is activated, a new brake cartridge must be installed before the saw can be used again.
10 SawStop 10" Industrial Cabinet Saw
Cabinet Saw Manual 1st Reprint.i10 10
®
safety system includes
other non-conductive
®
safety system is active whenever the Main Power is on. The safety system continuously performs
®
safety system. This revolutionary technology was developed to
Brake Cartridge
®
table saws
Fig. 1
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