5 Pin Relay Pinout

5 Pin Relay 5 pin relays provide 2 pins (85 & 86) to control the coil and 3 pins (30, 87 & 87A) which switch power between two circuits. They have both normally open and normally closed connection pins. When the coil is activated, power will be switched from the normally closed pin to the normally open pin.

What is 87A used for on 5 pin relay?

One of these will be used to ground your current, while the other will be connected to a switched power source. 87 and/or 87a will be connected to your controlled accessories that you wish to turn on and off with your relay. 30 will then be the pin connected to your battery power.

Which pin is ground on a 5 pin relay?

Pin 85 connects to the ground. Pin 87A - When the switch is turned off, power is drawn from this pin. It is not required to be used and can be completely ignored if not required.

Are all 5 pin relays the same?

The only thing they have in common, absolutely certain and guaranteed, is that they have 5 pins. Though it is likely, but not absolutely guaranteed, that 2 of these are the coil and the 3 others are the common, normally-closed, and normally-open contacts of a single-pole double-throw switch.

How do you tell which pin is which on a relay?

Every relay has a coin the white one which when energized activates the contacts. So of all the pins

Does a relay need to be grounded?

Generally, anything metal is required to be grounded… the base of a solid state relay is metal … so if the SSR is mounted inside metal enclosure, the enclosure must be grounded or covered for protection against dangerous voltages.

What is 85 and 86 on a relay?

85 and 86 are the coil pins while 30, 87, and 87a are the switch pins. 87 and 87a are the two contacts to which 30 will connect. If the coil is not activated, 30 will always be connected to 87a. You can think of this as the switch in OFF.

What does 86 mean on a relay?

Terminal 86 supplies power to the relay's internal electromagnet. Terminal 85 grounds the electromagnet. Terminal 30 supplies power to one of the internal switch contacts. Terminal 87 connects the other internal switch contact to the device controlled by the relay.

What does 87 mean on a relay?

Terminal/Pin number	Connection
85	Coil
86	Coil
87	Normally Open (NO)
87a	Normally Closed (NC) - not present on 4 pin relays

Is ground pin positive or negative?

And in electronics, ground is just a name we give to a certain point in the circuit. For example, in a circuit with one battery (with a positive and a negative terminal), we usually refer to the negative terminal as ground.

What pins to jump on relay?

The jumper cables are located on the right side of the engine compartment, behind the headlamp. To bypass the relay, you must be able to test the pins of the relay. Connect a positive jumper wire to terminal 86, 87, and 30. Make sure to use a long jumper to test the pins.

Which is ground on relay?

The second pin, or ground is the housing which must be mounted direct to chassis or otherwise grounded. If your relay is in a plastic housing it will have 2 pins for the coil, usually reversible. Your toggle switch is breaking the 12v power line between one side of coil and power.

What happens if you use the wrong relay?

Many relays, if installed for the wrong application, could and will cause a short (Internal Relay Circuit) and most likely cause functionality issues or even damage to the vehicle computer systems.

Do I need a diode on a relay?

In short, the diode takes the energy stored in the relay's coil when you switch the current off. Without the diode, the energy has no place to go and will cause a large and probably destructive voltage spike.

Are relays color coded?

No, there is no standardized meaning of the color of PCB-mount relays. Mostly it's a branding thing- a manufacturer will use a similar color for their line, maybe varying a bit for sealed relays, for example.

What is the common terminal on a relay?

The COM (Common) connection of a relay is the part of the relay that moves. When a relay is off, the COMMON is connected to the NC (Normally Closed). The NO (Normally Open) connection of the relay is not connected until the relay turns on. When the relay turns on, the COMMON move from NC to NO.

How do you read a relay?

Relays are electric switches that use electromagnetism to convert small electrical stimuli into larger currents. These conversions occur when electrical inputs activate electromagnets to either form or break existing circuits.

Can I use a 5 pin relay instead of a 4 pin?

Some 5 pin relays are SPDT (switch between the two pins) and some are DPST (like the main relay- connect 2 pins at the same time.) If you want to use a 5 pin in place of a 4 pin, you shouldn't have to remove the pin. The socket should be the same, but the center pin won't have a contact in it.

Do I need resistor for relay?

You only need a resistor in series with your relay coil if your are applying a voltage that is different than what your relay coil is rated for. At the rated voltage, the coil resistance will be sufficient to limit the current to the levels necessary to energize the coil.

Can I ground relay to battery?

For simple-circuit accessories (lights, relays, electric motors), battery ground is perfectly fine, though anything with a processor or that has high sensitivity to electrical noise or ground path should never use battery ground.