Relay 5-Pin 40A
*DC 12 V
*NC/NO
A 5-pin 40-amp relay is an electromechanical switch commonly used in automotive and other applications to control a higher-power circuit using a low-power signal.
It has five terminals: two for the control circuit (coil) and three for the switched circuit (contacts). The 40-amp rating indicates the maximum current the relay’s contacts can safely switch.
Key features and characteristics:
-
5 Pins:Unlike a 4-pin relay, a 5-pin relay has an extra terminal (often labeled 87a) which provides a normally closed (NC) contact in addition to the normally open (NO) contact.
-
40 Amp Rating:This means the relay’s contacts can handle a maximum current of 40 amps without overheating or failing.
-
SPDT (Single Pole Double Throw):This refers to the switching capability of the relay. It can switch between two circuits (one normally open and one normally closed).
-
12V Coil:Most automotive relays operate on 12V DC, meaning the coil is designed to be energized by a 12V power source.
How it works:
-
1. Control Circuit (Coil):When a small current is applied to the two coil terminals (usually pins 85 and 86), it creates a magnetic field.
-
2. Magnetic Field:The magnetic field attracts an armature, which is a moving part inside the relay.
-
3. Switching Contacts:The movement of the armature changes the state of the contacts (pins 30, 87, and 87a).
-
4. Switched Circuit:This switching action allows a higher current from a separate power source (e.g., battery) to flow through the relay’s contacts to a connected device (e.g., lights, horn, etc.).
Common Applications:
- Automotive: Controlling headlights, fog lights, horns, fuel pumps, and other high-current accessories.
- Industrial Control: Switching motors, solenoids, and other heavy-duty equipment.
- General Purpose: Any application where a low-power signal needs to control a higher-power circuit.
Reviews
There are no reviews yet.