Line vs Load – 5 Differences Explained

Line and load are 2 words that resonate in the electrical world. Before you work on connecting electrical devices together, understanding the concept of line Vs load is important.

What are the differences between these two? Read on to learn about the fundamental differences between line and load.

What Are Line and Load?

A line vs load is a wire which supplies electricity to your devices, such as a panel or switch. On the other hand, a load is a wire that easily takes electrical currents away from a machine.

Firstly, you must know what both sides mean. There are multiple kinds of line and load with unique properties. With respect to electrical wiring, line wires hold and transfer more power than load wires.

That is the main reason why line side wire is usually larger vs load side wire.

Line Vs Load Wire

Line and load wires are 2 separate entities and should not mix. If you are dealing with electrical connections, know these signs to avoid polarity reversal. Here are some parameters that can help you differentiate between the two:

Wire Positioning

Typically, the line wire connects to an electrical switch and comes from the bottom area. In contrast, load wires enter from above. Moreover, these line vs load points of connectivity has individual markings that help in indicating the type of wires for a point.


Color codes help in easy identification of various types of wires in an electrical circuit. However, there is not one standard code; they vary according to country.

Wire Size

Because electrical devices usually decrease voltage or current, line wire carries more power vs load wire. Therefore, line side wires are generally larger in size than load side wires. This characteristic is extensively visible if the power difference is enormous.

Measuring power features

Electrical power downstream from a unit is lower than upstream. Therefore, measuring the voltage or even current at the ends can easily differentiate between line and load wires. Also, volt sticks or pens and digital multimeters give a non-invasive measurement of these parameters.

Line And Load – Other Mode of Identification and Mix Up

Other than these methods, you should know that every device has indicators of its line and load side to so that the connections are proper.

However, if you reverse them, some may suffer from any consequences. An example of such a condition is a single-pole, single-throw switch. It works with perfection even after there is a reversal in connection.

But, in multiple switches, the connections are directional. Therefore, it will not work correctly if reversed.

Final Words

In a nutshell, polarity reversal creates a potential shock hazard, short circuit risk, or fire outbreak. So, it is better that you leave this in the hands of professionals. Appoint On Point Contracting for your electrical issues.

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