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12v Relay problem

rschuh54

New Member
Hi guys , im using a 12v relay powered from the arduino uno and im getting signal and the light comes on but no clicking ? am i stupid or is the relay stuffed? 1.jpg2.jpg3.jpg4.jpg
 

Musicmanager

Active Member
Sorry, scrub that .. .. .

It looks as though your trying to power a 12vdc Relay coil with 5vdc from the Uno .. ..
 

rschuh54

New Member
Sorry, scrub that .. .. .

It looks as though your trying to power a 12vdc Relay coil with 5vdc from the Uno .. ..
ive got the 5v from arduino going into the vcc on the relay, gnd to gnd. the 12 v dc plug is connected to the water pump with the negative split connected to NO and COM
 

Musicmanager

Active Member
Yes, but .. .. .. look what's written on the back of the relays .. the coils won't open with only 5vdc they need 12vdc
 

Musicmanager

Active Member
Yes .. .. .. ..

If you read the print on the back of the relay

12vdc is the coil - used to operate the switch

10A - 250vac - max load for the switch

15A - 125vac

you need a relay with a 5vdc coil

If you Google 5vdc Relay module there's loads of good examples

MM
 

rschuh54

New Member
Yes .. .. .. ..

If you read the print on the back of the relay

12vdc is the coil - used to operate the switch

10A - 250vac - max load for the switch

15A - 125vac

you need a relay with a 5vdc coil

If you Google 5vdc Relay module there's loads of good examples

MM
Thankyou so much, very appreciated!!
 

Pommie

Well-Known Member
Most Helpful Member
Do you have a link to the relay board? It looks like it uses opto-isolators to switch the relay and Vcc may need to be 12V (on the relay board only).

Mike.
 

rschuh54

New Member
It needs 12 V on the Vcc connection of the relay board.

Do not connect 12 V to the Vcc connection of the Arduino. That will damage it. You have to disconnect Vcc on the Arduino from Vcc on the relay board.
could i use a 5v relay instead and use the arduino?
 

Diver300

Well-Known Member
Most Helpful Member

crutschow

Well-Known Member
Most Helpful Member
could i use a 5v relay instead and use the arduino?
Yes, but it's likely cheaper just to buy a 12V wallwort to power the relays.
 

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