Data Sheet

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68. Safety Circuit
Build the circuit shown on the left, turn on the switch (62) and press
the press switch (61) and you will light up the LEDs at the same time.
Sometimes, for safety reasons, it is required that two switches be ON
before machinery will run.
69. Controlling Electrical Appliances
Build the circuit shown on the left. If you want to turn on the LEDs you
just need to turn on the switch (62) or press the press switch (61). If
you want to turn off the LEDs, you need to disconnect all the switches.
You might think this type of circuit could be used to have multiple
switches in a room to control the same device(s). However, this type of
circuit is not ideal because the switches do not toggle with each other.
In your house, if you pushed the switch (62) ON to turn on your lights,
then if you pressed the press switch (61) you would want your lights
to go OFF. Your house uses three-way switches to do this, and not the
circuit shown on the left.
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