The name of an electrical wiring diagram that uses standard component symbols is schematic or circuit diagram, but the exam is looking for the term schematic.
The other options are terms also often used in a set of build instructions for a device, but they are not the wiring diagram which is what the exam is asking about.
A schematic is the scheme (or plan) for an electrical circuit or device composed of electrical circuits.
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When drawing a "map" of a circuit it is not practical to try to completely label each part; instead, a standardized set of visual representations for the electrical components has been established. These are called Schematic Symbols, and the "map" of a circuit is also referred to as a schematic.
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Component 2 in figure T1 is a transistor. A transistor is a control element and has three terminals. The one on the left is called the base. It is the control input and is similar to pushing the gas pedal on your car; the little amount of power your foot puts into pushing the pedal creates a larger amount of power to come from the engine. The upper right terminal is the collector and has current flowing into it in porportion to the current into the base multiplied by the gain of the transistor (also called hfe or beta). The lower right terminal has an arrow that indicates the direction the current will flow from both the base and the collector.
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Component 3 in figure T-1 is an incandescent lamp. The small looping line inside the border shape represents the filament inside the lamp. Current flowing through the circuit causes the filament to glow and emit light.
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Component 4 in figure T1 is a Battery. This is the energy source to power the lamp when a voltage is applied to the input of the circuit. The symbol has one or more sections indicating a number of cells (piles) in the battery pack. The longer line represents the positive terminal while the shorter line is the negative terminal.
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A capacitor consists of two conductors (wires, plates, etc) separated by an insulator (such as air). If you look at figure T2 you will see that a capacitor has the symbol of two lines (one usually curved to indicate which side it is) with a gap between. Each line represents a conductor and the gap represents the insulator.
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The black arrow with a line across the tip (like component 5) is the schematic for a diode; a Light Emitting Diode has essentially the same characteristics of a diode except that it also emits light, therefore the schematic symbol looks like a diode with little zigzag arrows coming out to represent the light waves emanating from the diode.
A list of component schematic symbols can be found here: https://learn.sparkfun.com/tutorials/how-to-read-a-schematic
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A Variable Resistor is easily identified because it looks like a normal resistor (a jagged zig-zag line with straight lines entering and leaving) but with an additional arrow pointing at the middle of the zig-zag perpendicular to the rest of the component symbol. This arrow represents the brush or connection on the variable resistor (potentiometer) that moves when you adjust the resistance.
In the schematic symbol, the two ends have a total resistance between them of the total value of the resistor and the resistance between each end and the middle arrow varies.
A list of component schematic symbols can be found here.
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A transformer consists of two inductively coupled coils that are not directly connected together. If you look at the symbol you can see the representation of a coil on each side with two lines in the middle to indicate the separation.
A list of component schematic symbols can be found here: Schematic symbols
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The antenna schematic symbol looks a little like the stereotypical "satellite dish"; it's a triangle with one of the points connected to the circuit and the opposite side not connected to anything and a line through the middle. It is usually not hard to remember because it legitimately looks like an antenna =]
A list of component schematic symbols can be found here: Schematic Symbols
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An electrical circuit schematic is like a blueprint for an electrical system; another good analogy is a street map. the street map may not show all the trees, elevations, etc, but it does show what streets are connected together and where. Similarly an electrical circuit schematic diagram shows how all the components connect to each other and thus how the circuit works.
A schematic diagram does not show you where the circuits are physically located or what they look like, nor how far apart they are.
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