using relays in light control through keypad

[anitha ravi]

shall i use 8 pin relay instead of 5 pin relay?

 

[tpetar]

shall i use 8 pin relay instead of 5 pin relay?

All depends what you need and what relay is available to you.

Lets say, with 5 contacts you have NO and NC states, and with 4 contacts you have just one state usually NO.

NO - Normally Open
NC - Normally Connected

http://www.learningaboutelectronics...a-single-pole-double-throw-relay-in-a-circuit


Better buy relays with more contacts in your case 5 contacts, this give you more possibilities, also try to get relay with appropriate coil voltage according to your needs and projects, and look to get relay with higher coil resistance this will ensure lower current (300-400R and up).


Best regards,
Peter

 

[pranam77]

shall i use 8 pin relay instead of 5 pin relay?

Verify the 8 pin relay is having the same or more capacity at its contact ratings than the 5 pin relay you are using. 5 pin is called SPDT relay and 8 pin is called DPDT relay. If you intend to use 8 pin relay instead 5 pin, use one set of contacts and the coil and leave the other 3 pin unused or parelelly connect the two swicth blaocks to get better capacity.
Cheers