DPDT Switch Isolation

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=141620
Printed Date: May 01, 2024 at 11:14 AM

Topic: DPDT Switch Isolation

Posted By: pts760
Subject: DPDT Switch Isolation
Date Posted: August 16, 2016 at 6:58 PM

I'm working on a R/V for a customer. I have two DPDT switches that I want to control the awning with (folds out and folds in). One switch outside and one switch inside the R/V (Just like a 3-way switch in the house). If I daisy chain the two switches, the switches rest at ground and the fuse will blow when one of the switches are engage. Am I overlookering my wiring isolating dilema, or is there a better way to do this? posted_image

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I drink current, eat ohms, and bleed voltage

Replies:

Posted By: Ween
Date Posted: August 16, 2016 at 8:01 PM

Have the switches control relays. Remove the grounds from the switches, should have positive fold in and fold out. Wire relays to reverse polarity using positive trigger on coil. Switches are wired in parallel.

Posted By: pts760
Date Posted: August 16, 2016 at 8:32 PM

That's funny because before you posted your reply I was toying around with that idea and I believe thats gonna be the winner. One more question for you? Its probbably not likely but it is a possibility, what if someone is holding the switch up outside and down inside? I was thinking about adding a ATC auto reset breaker for circuit protection? Thoughts?

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I drink current, eat ohms, and bleed voltage

Posted By: Ween
Date Posted: August 16, 2016 at 8:44 PM

If the switches are operated simultaneously, the motor would stop as it would have positive voltage on each of its leads. No protection needed, except the fuse/circuit breaker present there now...hopefully.

Posted By: pts760
Date Posted: August 16, 2016 at 9:26 PM

Well I feel like a total idiot. Your right. Should have thought that one out a little more. thanx again for your help

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I drink current, eat ohms, and bleed voltage

Posted By: i am an idiot
Date Posted: August 17, 2016 at 4:01 PM

You have to use Momentary On-Off-On switches. If switches are used simultaneously and one tries to go in and the other tries to go out you will blow a fuse.

Posted By: howie ll
Date Posted: August 17, 2016 at 4:07 PM

Two momentary DPDT exactly the same as power window repeater switches in the good old days. Two SPAL switches in series, no relays unless the load exceeds 15 amps.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Posted By: Ween
Date Posted: August 17, 2016 at 4:43 PM

I'm guessing that since the vehicle in question is a RV, he has the switces. They probably match other switches in said vehicle...which is why I used relays.

Posted By: pts760
Date Posted: August 17, 2016 at 6:13 PM

Correct. I did already have the switches that rested at ground. The relays worked perfectly. Here's how it was wired.

posted_image

@ Howie II, I'm not familiar with those switches. Do you have a link that I could check those switches out for future applications?

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I drink current, eat ohms, and bleed voltage

Posted By: pts760
Date Posted: August 17, 2016 at 6:21 PM

Whoops. Diagram above is wrong. Correct Diagram:

posted_image

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I drink current, eat ohms, and bleed voltage