User's Manual

1918
(3) Install the ST wireless unit as shown in the illustration,
and then fit the top cover and secure it by tightening
the screw.
Tightening torque = 0.13 - 0.15 N·m {1.1 - 1.3 in.lbs}
* The shape of the top cover to be installed is different
for the ST-7900 and the ST-6700.
7. Basic Operation
Power supply (ON)
The power supply for each component is supplied by the following
operations and actions.
■ Main unit
The power supply for the main unit turns on when any one of the set
button, select button, button A or button B is pressed.
■ Speed sensor
The power supply for the speed sensor turns on when the magnet
passes over the speed sensor.
■ Heart rate sensor unit
The power supply for the heart rate sensor unit turns on when the
sensor unit detects that the electrode has been placed against your
body.
■ ST wireless units
The power supply for the ST wireless units turns on when you press both
the mode button and the lap button on the ST wireless units.
* The power does not turn on when a gear shifting operation occurs.
Sleep mode
(power saving function)
The power supply for each component switches to sleep mode by the
following operations and actions.
■ Main unit
The main unit switches to sleep mode if no
buttons on the main unit or on the ST wireless
units have been pressed for over 30 minutes, or
if there have been no signals detected from the
speed sensor or heart rate sensor unit.
If you hold down the set button and the select
button simultaneously for 2 seconds or more, it
will force the main unit to switch to sleep mode.
(If the stopwatch is currently operating or if the main unit is in setting
mode, it will not switch to sleep mode.)
■ Connection of the electric cables
Cable connection diagram
R: Right L: Left
ST-7970(L)
White
(For the SM-EW79F-E) (For the SM-EW79F-I)
ST-7970(R)
Red
ST-7971(L)
White
ST-7971(R)
Red
SW-7971(L)
Yellow
SW-7971(R)
Green
To derailleur
To derailleur