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need help designing relay circuit

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What i need to do is use a 24vac signal from my irrigation system to close contacts in a water softener control so it will backwash. The system is an irrigation controller with 10 zone outputs and a duplex water softener that has two control heads on it. All zone outputs from the irrigation controller are 24vac. The Softener control heads just need 2 pins to be jumped closed for 2 minutes to put the control head into backwash.

Here's how the system needs to work... zone 1,2,3,4 outputs are irrigation zones that power the irrigation valves for zone  Zone 5 output I am using to put the filter controller A into backwash. The softener controller has two pins on it that have to be closed for two minutes to put the softener into backwash. Zones 6,7,8,9 are for more water control valves and zone 10 puts the filter controller head B into backwash.

I bought two 12-24VDC relays and hooked them up but they chatter because of the 24 VAC input. I tried 2 diodes to make a circuit according to what I read online but they still chatter.

I'm thinking a capacitor now to smooth out the 24vac to the relay coils?

Or should i just buy two 24VAC relays?

I don't mind tossing the relays and diodes I bought and starting over.

Sense the current flow across the relay contacts is zero, its just making continuity, I guess any relay will work but they need to be small to fit in the irrigation controller.

Whats the simplest way to achieve my goals.  Get two new relays?  If so what 24VAC relays would you recommend.

Thanks Jim

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23 hours ago, jim02ss said:

Whats the simplest way to achieve my goals

I would think replacing the relays. You can get a pair of Omron 24 VAC relays for  11$ off Ebay. Omron has a good rating on Amazon.com

Else you can use a bridge rectifier to convert to cleaner (less ripple) dc. Search for "bridge rectifier diagram" for many diagrams on the  internet. A package with all four diodes in it is about 1$ on Ebay for example.


good luck



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