Specifications

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Control Relay Often refers to a device with contacts that open and close
electromagnetically, but solid state control relays are also
available. Control relays typically handle smaller currents than
contactors, but are capable of switching more rapidly.
Single-Pole
Single-Throw
Single-Break
Circuit 1
Double-Pole
Single-Throw
Single-Break
Circuit 2
Circuit 1
Circuit 2
Circuit 1
Single-Pole
Double-Throw
Single-Break
Single-Pole
Single-Throw
Double-Break
Circuit 1
Single-Pole
Double-Throw
Double-Break
Double-Pole
Double-Throw
Single-Break
Double-Pole
Single-Throw
Double-Break
Double-Pole
Double-Throw
Double-Break
Control Relay Contact Types
Coulomb A unit of electrical charge moved in 1 second by a current of 1
ampere. This is equal to approximately 6.24 x 10
18
electrons.
Coulomb’s Law A law that states that charged objects attract or repel each other
with a force that is directly proportional to the product of their
charges and inversely proportional to the square of the distance
between them.
Unlike Charges Attract Like Charges Repel
Counter EMF A voltage created in an inductive circuit that opposes a change
in current flow. EMF stands for electromotive force.
Current The flow of electrons in a circuit. Current is designated by the
symbol “I” and is measured in amperes.