Through the control coil. The coil then generates the magnetic field which moves the switch on and off.
Automotive Relays And How They Work
How does a 12 volt relay work. The current ratings vary from a few amperes to about 3000 amperes. Type of contact used whether it is a nc or no or closed contact. Ratings there are current as well as voltage ratings. Understanding how the relay works will help with diagnosis and modifications to vehicle systems. How they work when the coil is supplied with voltage a magnetic field is generated around it which pulls the hinged armature down onto the contact. In case of voltage ratings they vary from 300 volt ac to 600 volt ac.
This completes the high current circuit between the terminals and the relay is said to be energised. Online repair july 10 2015. 3 pin 4 pin 5 pin iso standardized relays iso relays were designed to try and standardize relay connections making it easier to test and design systems. Iso relays are. The magnet pushes a switch to the left forcing the spring contacts together and completing the circuit theyre attached to. All relays and contactors have some mechanical resistance and the electromagnetic coil needs to pull against that tension.
Items in a vehicle that require the highest amperage such as air conditioners engine fans starters and heater fans use 12 volt relays to keep the high amperage wires under the hood. Pull in voltage is the voltage required for the relay coil to energize and build enough strength the overcome the spring tension on the contact and pull it in. When the 5 pin relay is de energized off pins 4 and 5 have continuity. When the relay is energized on pins 3 and 5 have continuity. What happens inside a relay isnt magic but it is important. Looking at the diagram below you can see the pinout of a typical 12v relay.
Just an idea on how to wire each relay up. This is a relay from an electronic hot water immersion heater programmer. The spring holds the switch in position until a current gets passed through the coil. It is not desirable to run heavy duty wire into the cabin of a. There are also high voltage relays of about 15000 volts. Feel free to ask me anything.
The higher the amperage the thicker the wire and the greater the odds of a fire should a short in one of these wires occur. In this relay when a current flows through the coil it turns it into an electromagnet. In simple terms activate the relay. How does a 12 volt relay work. I know all about this stuff. If you were to open a relay you would see an electromagnet coil the switch and a spring.
Gallery of How Does A 12 Volt Relay Work
