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Automatic spoiler 'contest'

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Biba:


There are two incompatible pin outs for the automotive relay: https://www.12voltplanet.co.uk/relay-guide.html

Switch - is a single pole single throw or double pole double throw? I'm guessing a single pole single throw since that's the only switch I don't have.

Doesn't matter. An DPDT switch can substitute for a SPDT switch. You can just consider it as two linked SPDT switches if you like. You just don't use terminals. They also need something like (on)-off-(on) or on-off-on designations to indicate momentary() if desired.

Diodes. Not necessary for proof of circuit. A 1N4001, or 1N4002 wired across each with the BAND side toward the positive voltage.

Pay attention:
According to DIN 72552 the coil should be fed with +12V to terminal 86 and grounded via terminal 85, however in practice it makes no difference which way around they are wired, unless you are using a relay with an integrated diode (see more info on diodes below).

The limit switches need to OPEN when activated at the end of the respective travel. Those limit switches should be rated for about 1/2 amp. The relay coils are about 200 mA. https://www.panasonic-electric-works.com/pew/eu/downloads/ds_61202_en_cb.pdf

The schematic shows both limit switches open. So, do they close or open at a limit? It's a tough call, because it LOOKS like it shows that the spoiler is OPEN and CLOSED at the same time? That would be a good thing to check.

You can change lots of things and still have essentially the same circuit.

Shorting the motor via the (+) terminal is unexpected, but it will work. Switching +12 for the switch is reasonable.
 
I have this one figured out using an Arduino UNO and that GPS board. The limit switches inhibit the up & down relays from operating.

On powering up it is in automatic mode, all outputs are off and the GPS finds satellites and its position. When you accelerate to 62 MPH the spoiler goes up and stops when the limit switch turns off the up relay. When you decelerate to 42 MPH the spoiler goes down and stops when the limit switch turns off the down relay. This will continue unless you operate the dash switch, up or down. The limit switches inhibit that movement also. Once you operate the dash switch, it is in manual mode and will not raise or lower automatically again until you turn it off and back on.

BUT, the GPS takes 1 to 4 minutes to boot up, find satellites and its position.

It works fine with LEDs so my need to slay this Dragon is satisfied. If you still want it, you will have to persuade me to go buy relays, build a neat & orderly assembly on an Arduino prototype shield, build a test fixture from a sun roof motor with an arm and limit switches and drive around testing it to make sure it works as expected.

The circuit you showed last is good except that in the description of your spoiler, they say the limit switches are normally open and ground at the end of their stroke.
I would need confirmation on that point too.
 
KISS, did you actually read the URL I included? "Relays will generally operate just as well regardless of coil polarity, however it does come into play for one important reason. Since a relay is an electromagnetic device, the coil generates what is known as flyback when it deenergizes." That is why it needs diodes. Also, there are five schematics each showing the various steps of the opening and closing.

"A 1N4001, or 1N4002 wired across each with the BAND side toward the positive voltage," tells me nothing. I need the name/number of the Very Specific location.

For now, please answer - or any one else - my questions on the #20 post. I prefer to go with this (1 of 5) exact 'program'.
 
ClydeCrashCop, I'm concerned about not having limit switches. And if it needs to have a constant line of sight to a satelite, that could be a problem with trees and high buildings. My stationary SXM's antenna is facing South East and it is very clear. I used another SXM unit on my vintage Alfa years ago. Once I was inside the car it would not work. I'd step out and it would come on. I could never get it to work when I was inside. What especially concerns me with this 'arrangement' is it might only work some of the time.

That said and using a different example, it is my understanding that signals can be sent to newer car’s BCM’s. I’m assuming it is by using GPS. If this is correct, my assumption is the signal is passed from one GPS to another, etc. Correct?
 
ClydeCrashCop, I'm concerned about not having limit switches.

When you accelerate to 62 MPH the spoiler goes up and stops when the limit switch turns off the up relay.
When you decelerate to 42 MPH the spoiler goes down and stops when the limit switch turns off the down relay.
This will continue unless you operate the dash switch, up or down.
The limit switches inhibit that movement also.

The limit switches work under ALL circumstances.

The GPS works inside my house and inside my van.

Here is all the info on the GPS. you can look at the specs and instructions.

GPS Module with Ceramic Antenna for DIY Handheld Positioning System for $7.86

https://www.dx.com/p/open-smart-gps...ino-apm2-5-flight-control-480918#.WiDKElWnH4Y

This is the data, info & an Arduino sketch that works out of the box.

https://drive.google.com/drive/folders/0B6uNNXJ2z4CxVGtacFJiM1B6OTQ?usp=sharing
 
"A 1N4001, or 1N4002 wired across each with the BAND side toward the positive voltage," tells me nothing.
That tells you everything.

flyback diode.jpg
 
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I'm not sure if you checked out the spoiler I'd downloaded back in May 2016. A is the switch that (now) opens and closes the spoiler; B is the three limit stop's wires (not needed?); C is where I'd hoped to install the 'unit' if it would fit. However the problem now would be the GPS has to 'see' through three sheet metals. If everything else can fit in the space 3/4" next to the silver part to 3/16" at the right end. The dimensions are 5" x 2 1/2". If there is truly an exterior GPS antenna that will work (though I hate to stick stuff on the outside) that might be best. However I have no way of coming up with a 3.3 to 5.2 voltage.

Obviously I'll take your word as to how the relays and diodes are included.
 
Clyde covered it very well and I hope much better than I could. Thanks.

It's not really a "flyback pulse". It essentially means 12 V stays at the relay terminals until it decays. It can decay through something that can be damaged which is usually a transistor. All, I meant to say was, the diode is not required for testing but improves reliability in the long run. It makes sense to make the external diode the same as the diode placement used in a relay with an integral diode.

The diode is small, so it can be soldered to the relay Faston's. For those doing it the hard way with individual wires: https://www.walmart.com/ip/Painless...9971&wl11=online&wl12=198936377&wl13=&veh=sem

So, a 1N4001: **broken link removed**

So, confirm if the switches are closed or open at the limits? Use ohmmeter. Both open, both closed?, spoiler position (part-way, fully up, fully down). Part way, is probably the best position to take the measurements in. You know which terminals are the up or down limit, so mention those too.

No one has ever asked if the switches are accessible or could be re-wired?
 
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