Teledyne 4250 Installation And Operation Manual page 55

KEYPRESS TIMEOUT will cause the backlight to be turned on
whenever you press a key on the keypad (other than On and Off).
An internal timer is started that will keep the backlight on for
approximately two minutes after you press a key.
Each time you press a key, the timer is restarted, so the backlight
will never go off as long as you continue to program the flow
meter, with keystrokes coming less than two minutes apart. At
the end of programming, the backlight will go out, and will stay
out until you start to program again.
This feature is designed to conserve battery power by de-ener-
gizing the backlight when it is not needed. The backlight is still
available if it is necessary to program in a dark environment,
such as a manhole. We recommend using this selection if the flow
meter is battery-powered, but installed in an environment where
the lighting is poor.
CONTINUOUS will cause the backlight to be lit continuously.
Where the flow meter is powered by an AC power supply, battery
life considerations do not intervene. If the backlight makes the
display easier to read, use it. Do not use CONTINUOUS in any
installation that is battery-powered, as it will cause rapid dis-
charge of the battery.
OFF will keep the backlight feature turned off under all circum-
stances. Select this option for maximum battery life in installa-
tions where there is sufficient ambient light to read the display
without the backlight feature.
Press Enter. The SETUP menu will return. This time move the
flashing cursor from LCD BACKLIGHT to LANGUAGE.
When LANGUAGE appears on your display, you may select an
alternate language for programming. The other language
depends on how the flow meter was ordered. The following
display will appear:
LANGUAGE
• ENGLISH • • (second language, as ordered) •
Select the language appropriate for your application. The menus
and the printed reports will appear in the selected language.
Press Enter. The SETUP menu will reappear. This time select
PROGRAM LOCK from the menu. Press Enter:
PROGRAM LOCK
• ON • • OFF •
PROGRAM LOCK keeps the program from being changed. Select
OFF while you are programming, and then go back and select
ON if you need to lock the program. At that, we suggest using the
lock only if there are compelling security reasons.
Further changes will require entry of the password, which is the
model number of the flow meter: 4250. If you select ON, there is
a time-out before the lock engages.
4250 Flow Meter
Section 2 Programming
2-27