What are the different terminal numbers for relays?

What are the different terminal numbers for relays?

In addition, the terminal numbering is different, using 1, 2, 3, 4 & 5 instead of 30, 85, 86, 87 & 87a. There are other relay designs that are used for some more complex applications in vehicle systems.

How can I find out if my relay is working?

Determine the coil requirements of the relay. The manufacturer’s part number should be listed on the case of the relay. Look up the applicable data sheet and determine the voltage and current requirements of the control coil. This also may be printed on the case of larger relays. Find out if the control coil is diode protected.

Where can I find the contact configuration of a relay?

Assess the contact configuration of the relay. This will also be available from the manufacturer’s data sheet, or may be printed on the case of larger relays. Relays may have one or more poles, indicated in drawings by a single line switch connected to a pin of the relay. Each pole may have a normally open (NO) and or normally closed (NC) contact.

How to test the energized condition of a relay?

Check the energized condition of the relay contacts. Use a digital multimeter (DMM) to test the resistance between each pole of the relay and the corresponding NC and NO contacts for that pole. All NC contacts should read infinite resistance to the corresponding pole.

How does a normally closed contact relay work?

Normally-closed contact relays work the opposite way: The contacts are closed when the relay is de-energized. Energizing the control circuit in the relay opens the contacts, shutting off the current in the load circuit. Dual-contact relays have one set of normally-open contacts, and one set of normally-closed contacts.

What kind of relay is used in a circuit?

Relays that are normally used in electronic circuits are SPDT and DPDT types due to their flexibility in controlling circuit switching. In the next section, a demonstration on identifying the pins of a relay from SPDT or DPDT type without referring to its datasheet will be illustrated.

How to determine the number of pins in a relay?

Try to touch the probes of multimeter on remaining pins to determine which are the pins actually connected with each other.These pins actually consist of normally closed (NC) pin/pins and common pin/pins. Based on this finding, the remaining pins must be normally open (NO) pins. **In this case, there is only 1 pair of pins found connected.

What do you need to test a relay?

To check for faulty relays, you’ll need: Organizing your tools and gear so everything is easily reachable will save precious minutes waiting for your handy-dandy child or four-legged helper to bring you the sandpaper or blowtorch. ( You won’t need a blowtorch for this job.