RELAY 1. NORMALLY CLOSED 2. NORMALLY OPEN Basically, an electrically operated switch which may be normally closed (1) or open (2). Current flow through a small coil creates a magnetic field which either opens or closes an attached switch. RELAY, DOUBLE THROW A relay which passes current through one set of contacts or the other. RESISTOR An electrical component with a fixed resistance; placed in a circuit to reduce voltage to a specific value. RESISTOR, TAPPED A resistor which supplies two or more different non adjustable resistance values. RESISTOR, VARIABLE or RHEOSTAT A controllable resistor with a variable rate of resistance. Also called a potentiometer or rheostat. SENSOR (Thermistor) A resistor which varies its resistance with temperature. SENSOR, ANALOG SPEED Uses magnetic impulses to open and close a switch to create a signal for activation of other components. SHORT PIN Used to provide an unbroken connection within a junction block. SOLENOID An electromagnetic coil which forms a magnetic field when current flows, to move a plunger, etc. SPEAKER An electromechanical device which creates sound waves from current flow. SWITCH, MANUAL 1. NORMALLY OPEN Opens and closes circuits, thereby stopping (1) or allowing (2) current flow. 2. NORMALLY CLOSED SWITCH, DOUBLE THROW A switch which continuously passes current through one set of contacts or the other. SWITCH, IGNITION A key operated switch with several positions which allows various circuits, particularly the primary ignition circuit, to become operational. SWITCH, WIPER PARK Automatically returns wipers to the stop position when the wiper switch is turned off. TRANSISTOR A solidstate device typically used as an electronic relay; stops or passes current depending on the voltage applied at "base." WIRES (1) NOT CONNECTED Wires are always drawn as straight lines on wiring diagrams. Crossed wires (1) without a black dot at the junction are not joined; crossed wires (2) with a black dot or octagonal (◇) mark at the junction are spliced (joined) connections. (2) SPLICED 17