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What a timer
switch is used for
Timer switches are extremely useful circuits for
making life a little more comfortable. Here are a
few examples to show you the kinds of things they
can do:
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The inside light of a car should only go out after a
certain delay, so you can easily insert your key
into the ignition even when it's dark out.
→
An alarm should only come on after a certain
delay, so the proper owner has enough time to
turn the system off after opening the door.
→
A pedestrian light should only switch from red to
green a few seconds after the button has been
pushed.
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To save electricity, stairway lights in apartment
houses should only shine for a few minutes before
turning themselves off.
TIMER CLOCKS
A timer clock is a clock that switches
an electrical contact on or off at a
specified time. The switching times can be
individually adjusted. Electronic timer clocks can be
used to switch a water system on or off at a certain
hour, or example.
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