BenQ CP120C - Manual (Page 41)

Using the projector 35
High Altitude
Mode (Off)
If you use this projector under other extreme conditions excluding the
above, it may display auto shut-down symptoms, which is designed to
protect your projector from over-heating. In cases like this, you should
switch to High Altitude mode to solve these symptoms. However, this is
not to state that this projector can operate under any and all harsh or
extreme conditions, or whenever the projector will be used for extended
periods of time (>10hours) without shutdown.
Auto Off (Off)
This function allows the projector to turn off automatically if no input
signal is detected after a set period of time. Press Left
3/ Right 4on the
projector or remote control to set the duration before the projector is
turned off. Selecting Off disables this function.
Economic
Mode (Off)
Use this mode to reduce system noise and reduce power consumption by
20%. If this mode is activated, the light output will be reduced and result
in darker projected images.
Setting the projector in Economic mode extends the lamp timer
automatic shutdown feature. For more information on how the total
lamp hour is calculated, see "Calculation of lamp hour" on page 38 .