How to check whether the relay is good or not? What are the general testing methods?

Date：2022-11-11 14:34:59Views：1177

Relay is an electrical control device, which can make the controlled quantity have a predetermined step change in the electrical output circuit when the change of input quantity (excitation quantity) meets the specified requirements. In the circuit, the relay plays the role of automatic regulation, safety protection, conversion circuit, etc. The following is a small compilation of relay detection quality related content, hoping to give you reference and help.

How to check whether the relay is good or not?

1. Check the relay solenoid coil

For step relay, it is similar to the detection method of electromagnetic relay. We can use the resistance gear of the multimeter to measure whether the coil of the step relay is normal. If the solenoid coil of the relay is damaged, the measured resistance value will be 0. From this, it can also be determined that the relay has been damaged.

2. Pressurization inspection

If the coil is found to be in good condition through the above steps, we need to use the DC power supply with the voltage that the relay can withstand, connect the positive pole of the power supply to one end of the coil, and then touch the other end of the coil with the negative pole of the power supply. If the relay is not damaged, then the built-in components of the relay will produce some work, making or breaking contacts. If not, the relay is damaged.

For the step relay, if the mechanical system does not act after the coil is applied with the drive pulse voltage, it indicates that the step relay has been damaged.

After seeing the good or bad inspection of the relay, let's take a look at the inspection knowledge of other aspects of the relay.

Other detection methods of step relay

1. Measuring contact resistance

When the relay is in good condition, the measured resistance of normally closed contact and moving point should be 0 under the measurement of the resistance of the multimeter. Then, through this method, we can easily know which is the normally closed contact and which is the normally open contact.

2. Measuring coil resistance

Available multimeter R × Measure the resistance of the relay coil at the gear of 10 Ω to determine whether there is an open circuit in the coil.

3. Measure the pull in voltage and current

The adjustable regulated power supply and ammeter were obtained, a set of voltage was input to the relay, and the ammeter was connected in series in the power supply circuit for monitoring. Slowly increase the power supply voltage. When you hear the closing sound of the relay, record the closing voltage and current. For accuracy, you can try several times to calculate the average value.

The detection method of the relay has been discussed in detail above, so let's take a brief look at the function of the relay to help you better understand the relay.

Function of relay

1. Expand the control range: For example, when the control signal of the multi contact relay reaches a certain value, the multi circuit can be switched, disconnected and connected simultaneously according to different forms of contact groups.

2. Amplification: for example, sensitive relays, intermediate relays, etc. can control circuits with high power with a very small control quantity.

3. Integrated signal: For example, when multiple control signals are input into the multi winding relay in the specified form, the predetermined control effect can be achieved through comparison and integration.

4. Automatic, remote control and monitoring: for example, the relay on the automatic device can form a program control circuit with other electrical appliances to achieve automatic operation.

The above is the relay detection method related content compiled by the wound core detection team, and I hope it will be helpful to you. Our company has a team of professional engineers and industry elites, and has built three standardized laboratories with an area of more than 1800 square meters, which can undertake a variety of test projects such as electronic component test verification, IC authenticity identification, product design material selection, failure analysis, functional testing, factory incoming material inspection and tape weaving.