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  Bosch Relay
     Bosch Relay
Bosch Relay
Price $ Depends on quantity
Single Relay Price $ 5.95
3 or More Relay Price $ 5.00
12 or More Relay Price $ 4.50
  • Instructions included
  • Relays included
Downloadable Manual PDF

Relays are widely used in electrical applications where one circuit is to be energized or turned "on" by the presence of a power, provided by another circuit. For example when an automotive radio sends out a triggering voltage to turn on an external amplifier or activate a motorized antenna. Anywhere a switch can go in a circuit, a relay can replace it, (as long as there is a triggering voltage available to activate it).
The "switch" in a relay is often called a electromagnet switch. Which is basically a motorized switch, that allows positive or negative to pass when activated. This will be determined based on installation. A relay can be triggered with an electrical pulse as small as 150 milliamps.
The switched output can be as high as 30 amps.

The terminals of a relay :

30 is the common or input voltage (or ground) to be switched.
87a is the normally closed connection (A relay rest at 87a to terminal 30).
(This terminal offers no continuity when the relay is energized.)
87 is the normally open connection (switched voltage output when the relay is energized).
85 is connected to the ground of the triggering voltage.
86 is connected to the positive 12V of the triggering voltage.
85 & 86 can have the polarity reversed.
At Rest (Continuity from 30-87a) Relay Activated
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