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Now you got it. Glad it works for you.

However, that is not a SS relay.

It is a coil relay driven by a transistor input.

A "real " solid state relay uses optical isolation and the input uses no reference or is isolated from ground, which is why you can put the input across anything and not blow shit up as no connection gets grounded.
 

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Discussion Starter · #42 ·
Damn ok.. That is pretty much what I've been looking for. I am going to order the DC to DC 25A version of that SSR you referenced? Will I need to utilize the heat sink for such a low load?
 

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Discussion Starter · #43 ·
Some of the reviews are saying this thing triggers at 3v. The led only puts out about 2v. I guess I'm trying to understand the risk of "blowing shit up" with my coil driven relay? I'm going to try the SSR either way.
 

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You say it works as is and no smoke.

"Blowing shit up" ok, here is the explanation:

Your coil relay has a connection to ground (negative) return, whatever you want to call it.

You are connecting that to the LED lead that goes to the current limiting resistor (in series) which goes to a device that switches it to ground, ergo the LED lights.

As you can tell, when triggered, the coil relay which has a 12 volt source, will sink current through the LED current limiting resistor as well.

If the current is enough, you get a POOF, and the resistor smokes.

It appears the resistor can handle the increased load, so I wouldn't worry.

If the circuit you are using had a dedicated ground/return and it was connected, then you would sink the LED current and it would go POOF (no current limiting).

If you do use the SSR, you may have to solder across the current limiting resistor to get enough trigger voltage.

You would not need the heatsink, unless your vibrate motor is a current hog.
 

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Well, I'm fuckin' lost. Anybody else?
 

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Discussion Starter · #48 ·
Haha. The solid state relay did not fire on 1.95vdc from the alert led. So back to the transistor relay.
 

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Haha. The solid state relay did not fire on 1.95vdc from the alert led. So back to the transistor relay.
Connect the SSR input across the resistor that is connected in series with a lead of the Alert LED.
That is the current limit/voltage dropping resistor for the LED.
You should get about 10 volts when the alert LED is lit.
That should give you plenty of voltage.
 

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Discussion Starter · #50 ·
sooo... If anyone cares here is the finished product. I did end up grounding the relay thru the led ground but from my research the relay side of it only draws a few mA. The motor side ground is separate. The haptic motor vibrated a little too hard for me, so after burning out a 100k pot, I got a Pulse Width Modulator to turn it was down. I put everything in an ABS enclosure box I found on Amazon.

Product Circuit component Rectangle Font Parallel
 

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Now that you've finished this, my wife's vibrator triggers my radar detector. 😀
 

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Discussion Starter · #52 ·
Hey as long as it saves you from a pesky speeding ticket vibrate whatever you want!
 
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