VSS activated switch

If you are going to make one of those gadgets for yourself, I'd be willing to pay you to make a second for me.

It seems like if it could be made to fire a relay at anything less than 5 to 10 mph, it would work great.

It would also be less wear on the lock-out solenoid too since it wouldn't activate every time you hit the brake.
 
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If you are going to make one of those gadgets for yourself, I'd be willing to pay you to make a second for me.

Well here's the thing.. I do not yet have a t56 to test it with so I have no reason to make one for myself but I'd like to try to make one just for the fun of it.
 
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If you are going to make one of those gadgets for yourself, I'd be willing to pay you to make a second for me.

Well here's the thing.. I do not yet have a t56 to test it with so I have no reason to make one for myself but I'd like to try to make one just for the fun of it.
Too bad we don't live closer.

Seems like if it were programmed to close a switch at anything lower than 2,000 pulses per minute, It would be good enough whether it the VSS was 12 or 17. If the switch is normally closed then it could just open it at anything above 2000.

In my case, 2000 pulses per minute would be about 4 mph. Right?
 
If you are going to make one of those gadgets for yourself, I'd be willing to pay you to make a second for me.

Well here's the thing.. I do not yet have a t56 to test it with so I have no reason to make one for myself but I'd like to try to make one just for the fun of it.
Too bad we don't live closer.

Seems like if it were programmed to close a switch at anything lower than 2,000 pulses per minute, It would be good enough whether it the VSS was 12 or 17. If the switch is normally closed then it could just open it at anything above 2000.

In my case, 2000 pulses per minute would be about 4 mph. Right?

I agree. It would some tinkering. With the arduino, you use the interrupts to count pulses so we'd just have to determine what is an acceptable loop timer time since you probably wouldn't want to potentially wait 60 seconds after stopping before it closed the relay and you could throw it into reverse.

2000 pulses per minute is 4mph for you, and about 3 mph for those with the 17 pulse VSS. I think that would be perfect. If memory serves me correctly, the factory ones work under 5 mph.

I think we could start with the timer at 2 seconds.. If it sees one pulse (or more) every two seconds then the relay would be opened.
 
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Is the GM VSS sign wave or square wave? And does that make a difference with detecting the pulses with this unit?
 
According to the jags that run site, the GM VSS will be sine wave. I think that is something that would need to be confirmed.

And as far as I can tell, the interrupts detect when it's pulled high / low so it will (should?) detect both.
 
Anyone have an idea what kind of current the reverse lockout solenoid draws?
Why does that matter if running a relay? I would guess it's on the order of a couple of amps.

I was looking at the relay shields (expansion boards) for the arduino and the ones I found are pretty light duty.. like < 1.5A

There has to be something a little stouter since people use these to build those crazy fighting robots.

Blah.. It'd be easier just to use a mechanical relay instead of an ssr.
 
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I just read the instructions on the Accutach unit and it says the T56 solenoid draws 1 Amp. Looks like the unit is designed to handle that and doesn't require an external relay.

The unit is $80 with shipping but if it works as it says I think it's worth it.

What's your take on it Pancake?
 
I say go for it. You'd likely be into a home built project for around $80 anyway.
That's what I figured too.

They have a "send a message" form on their contact page and I sent one just asking them to verify 100% that it will work with my setup. I haven't heard back from them yet.
If I don't hear back today, I will call them. Sometimes these companies just don't check their messages.

I got burned on that SAS thing I bought. (Stupid me to buy 2 of them too). Plus, I bought those things way in advance of needing them so it's way, way past any point of asking them for any money back.

What about you? Are you going to make your own just for the fun of it?
 
I am planning the t56 swap for the spring since I just burnt through my parts budget. I will likely try to make one, though. I have wanted to start experimenting with I/O boards so this would make a good project.
 
Just got a response and I went ahead and ordered one.

Nice response:

"Roger,

From what I know, all of the T56s use the same OSS sensor and 12 tooth reluctor wheel, so my unit will work with all of them. In fact, it would even with with the same sensor with a different tooth count. This works because the sensor produces an AC signal which increases in both frequency and voltage as the speed goes up. My unit detects the voltage, not the frequency, so it works just about anywhere. The only place I have seen my unit not work is in cars with a Dallas Mustang Speedcal installed. In that case, my unit will still work, but the input signal to my unit must be taken from inside of the Speedcal device rather than directly from the OSS.

If my unit does not work for you for any reason, I'll give you a full refund (less shipping). But I am 99% sure it will work great in your application.

I'm running low on inventory. Looks like I'll need to build a new batch. :)

Regards,

Mark"
 
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