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The T20 timer has a hidden security lock. When activated, the lock disables the
programming button P and prevents access to the T20’s menu.
To lock or unlock the T20, press the up and down buttons together while the pump
is in normal operation (not while it is being programmed). Pressing the up and
down buttons together while in normal running mode shuts down the pump and
opens the timer’s lock screen. Once the lock screen is displayed the timer can
be locked or unlocked by pressing the up or down buttons. Pressing P then exits
the lock screen and the timer resumes normal operation. When locked, pressing
the P button has no effect on the timer and does not take you into the menu in
the usual way. Access to the menu can then only be obtained by first unlocking
the program.
Program Lock
LCD Screen Back Light
The LCD screen on the T20 timer has a built-in backlight. The backlight switches
on automatically whenever you are programming the timer and when the T20 is
displaying certain fault conditions. In normal operation the backlight remains off.
The LCD screen backlight can be switched on manually at any time by pressing
and holding down the down arrow button. The screen will remain illuminated
while you are depressing the down button. The screen will switch off as soon as
you release the button. The LCD backlight can’t be permanently switched on, it
only operates while the down button is held in.
Maintenance
The T20 timer is a low maintenance device. If it is correctly installed in a location
that is out of direct exposure to the elements it should give a long and reliable life
and require little or no maintenance at all.
Factors that may reduce its life are lightning strikes or power surges, failure to
fully tighten lid or cable glands, exposure to temperatures in excess of its ratings
and operation outside its electrical limitations in terms of supply voltage and mo-
tor loads. Spare parts are available for the T20 timer from your supplier.
Summary of Contents for T20
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