5 pin relay diagram

1. How does a 5 pin relay work?
2. What is 87 and 87a on a relay?
3. What is a 5 pin vs 4 pin relay?
4. What is 85 and 86 on a relay?
5. Can I supply 12V to 5V relay?
6. What is L1 and L2 in a relay?
7. Is 85 always ground?
8. What is A1 and A2 on a relay?
9. How do you know if a relay is bad?
10. What is the easiest way to test a relay?
11. How does a relay work?
12. What happens if you put a relay in backwards?
13. How does a 12v change over relay work?
14. Are all 5 pin relays the same?
15. Do relays need AC or DC?
16. Does relay works on AC or DC?
17. Why is relay AC or DC?

How does a 5 pin relay work?

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 87 and 87a 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. Think of this as the relay in the Normally Closed (OFF) position.

What is a 5 pin vs 4 pin relay?

The “Bosch style” relay is also known as a 5-pin, 5-prong, SPDT, or changeover relay. As compared to a standard 4-pin SPST relay (with terminals 85, 86, 30, and 87), the 5-pin Bosch relay has an extra terminal 87a, which is powered only when the relay is not energized.

What is 85 and 86 on a relay?

Realizing that 85 and 86 are the coil pins, these pins will be transferring the current through the coil. 85 will be used to ground your relay, while 86 will be connected to the switchable power. 87 and 87a will be connected to your controlled accessories that you wish to turn on and off with your relay.

Can I supply 12V to 5V relay?

12V will definitely damage the relay board.

This 2 channel relay board requires about 200mA at 5V with both relays energized. I suppose the simplest solution would be to use a 5W, 6.8V zener diode connected in series with 12V to drop it to 5.2V.

What is L1 and L2 in a relay?

1. The two vertical lines that connect all devices on the relay logic diagram are labeled L1 and L2. The space between L1 and L2 represents the voltage of the control circuit. 2. Output devices are always connected to L2.

Is 85 always ground?

(Note that if the circuit is for a horn, most horns are switched on the negative side of the control circuit, not on the positive. That is, on a horn, 12V should always be present on 86, and 85 is grounded when the horn button is pressed).

What is A1 and A2 on a relay?

What Do A1 and A2 Mean on a Contactor? A1 and A2 on a contactor typically refer to either end of the electromagnetic coil assembly. Most contactor manufacturers use A1 and A2 to designate the two terminals connecting electrical power to the contactor's magnetic coil.

How do you know if a relay is bad?

The only tool required to check a relay is a multimeter. With the relay removed from the fuse box, the multimeter set to measure DC voltage and the switch in the cab activated, first check to see if there are 12 volts at the 85 position in the fuse box where the relay plugs in (or wherever the relay is located).

What is the easiest way to test a relay?

Take the leads of the multimeter and connect them across the coil terminals of the relay. For a normal coil, the multimeter should read anywhere between 40Ω to 120Ω. If the coil is damaged i.e., it is open, the meter shows out of range and you have to replace the relay.

How does a relay work?

The relay permits a small amount of electrical current to control high current loads. When voltage is supplied to the coil, small current passes through the coil, resulting in a larger amount of current passing through the contacts to control the electrical load.

What happens if you put a relay in backwards?

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.

How does a 12v change over relay work?

Relays install between the power source and the electrical accessory requiring on/off power. When the relay is energized, the high current to operate the accessory flows from the power source, through the relay, and directly to the part.

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.

Do relays need AC or DC?

The operating voltage of a relay is generally in DC. Small signal relays and low voltage power relays are usually in DC, but mains control relays and contactors quite frequently have AC coils. The rest of the terminals of a relay are used to connect either a AC(generally 50/60Hz) or DC circuit.

Does relay works on AC or DC?

Just as it is impractical to operate a DC relay from AC, it is likewise impractical to operate an AC relay from DC. However, in an emergency, an AC relay may be operated from DC—provided certain precautions are taken.

Why is relay AC or DC?

The working power of the AC relay is AC, and the working power of the DC relay is DC. The coil diameter of the AC relay is thicker and the number of turns is less, and the coil diameter of the DC relay has more turns than the thin wire diameter. The core of the AC relay has a short-circuit ring, and the DC does not.