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Do switches need relays?

Do switches need relays?

One of the most common situations that require the use of a relay occurs when an application needs to switch from high to low current (or vice versa) within the same circuit. For example, the temperature sensors that power HVAC units require levels of amperage that vastly exceed the capacity of their wiring.

Do I need a relay?

A relay is an electrical switch that lets a low current circuit control a high current circuit such as a large LED light bar. If you are using a light pod that does not have a very large amp draw, you may not need a relay switch, but if you are using a larger LED light bar, they are a must have.

Why do lights need a relay?

Using a relay keeps the high current portion of the circuit from the switch and pulls the current directly from the battery to your KC’s. The relay also allows you to tie your lights into a secondary 12-volt circuit such as your high/low beams or ignition.

What is the purpose of a relay in a car?

Relays are switches controlled by electrical power, like another switch, computer or control module. The purpose of an automotive relay is to automate this power to switch electrical circuits on and off at particular times.

Why relay is used instead of switch?

Relays are used when you want to provide AC power to a device but your actuation control is DC. So by providing DC power to Relay you can actuate an AC powered device. In case of switches it will be either DC controlled DC powered device or AC controlled AC powered device.

What is the benefit of a relay?

The major benefit of a relay is isolation. In some conditions, one circuit has high current or high voltage, while the controller is operating with low voltage/low current, we can use a relay to switch on and off high power circuitry without causing damages to the low power controller.

What is the purpose of a relay?

Relays are switches that open and close circuits electromechanically or electronically. Relays control one electrical circuit by opening and closing contacts in another circuit. As relay diagrams show, when a relay contact is normally open (NO), there is an open contact when the relay is not energized.

Does car horn need relay?

The OEM horn draws somewhere between 1.5-2 amps. I tried the same with the sickspeed horn and the voltage drop was so high that the horn wouldn’t sound. So, yes a relay is definitely needed.

Can you use a switch as a relay in a car?

If you use a vehicle’s stock wiring and switches to control aftermarket devices like high-output lighting, relays will not overload or stress the OEM components. The average automotive relay can also handle a much higher current load than a switch (about 30 amps vs. 3-20 amps).

How many amps can a 5 AMP relay handle?

Relays often have two ratings: AC and DC. These rating indicate how much power can be switched through the relays. For instance, a 5 Amp relay rated at 125VAC can also switch 2.5 Amps at 250VAC. rated at 24VDC can switch 2.5 Amps at 48VDC, or even 10 Amps at 12VDC.

Do I need a relay for my headlight switch?

Most standard switches are not able to “hot switch” higher current loads (i.e. headlights). I am running an electric fan off of a 1A toggle switch with an inline fuse. Works fine. A relay is a REALLY GOOD idea on ANY high amp draw electrical device… from Denver, CO.

Do I need a relay for an electric fan?

I am running an electric fan off of a 1A toggle switch with an inline fuse. Works fine. A relay is a REALLY GOOD idea on ANY high amp draw electrical device… from Denver, CO. when I test wired my fan it worked great, then when I wired it for real I kept blowing fuses and the fan would surge. Really depends on your switch.

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