The simple method explained. (The LED and switch are somewhat unknown)
Take a look here: http://www.robmeyerproductions.com/bows.html at the first figure. I don't LIKE it, BUT it gives you an IDEA how things COULD be wired. In that diagram, the limit switches are INDEPENDENT which is not your case and the motor moves with a low current signal. Protection diodes are not in place either. The important thing is that the limit switches don't carry the full motor current. That wiring diagram SUCKS!
Your wiring would look MORE LIKE this
diagram.
The "SPDT" Automotive relays are available in a dual configuration with plugs and wire leads. e.g. **broken link removed**
When your finished wiring the contacts, you have a relay for up and one for down. Because the motor is shorted with both off or even both on, the motor stops instantaneously.
Now, your choice if you want common + or common negative.
NO LIMITS yet. SUPPOSE the limit switches close on UP and close on DOWN and have a common terminal. So, you want to wire the limit switches so that they activate their corresponding small 12V DPDT relay such as http://www.digikey.com/product-deta...mfield-relays/9-1462037-9/PB1181CT-ND/1828471
So, with 12 V common to the small relay and the coils going to ground via the limit switch, we now have 2 independent contacts.
We wire one set of the independent contacts such that the EXTEND relay is not allowed to extend if the EXTEND LIMIT relay is activated. We do the same for retract. These little relays activate when they are at their corresponding limits and one of their SPDT contacts won't allow (Opens) the EXTEND or RETRACT signal to get through to the other relay.
So, we have a set of SPDT contacts left. We arrange these in parallel like an OR Gate, so you get a single contact that's closed when the motor is not at either limit. So, we can arrange the contact (direction and appropriate resistor) to activate the LED when the motor is somewhere in the middle.
We can ""play a game" and but a full wave bridge rectifier across the motor and power that LED from the motor power. Now if the motor fused blew (sized to protect) there would be no power to activate the LED when the spoiler is in the mid position.
So, you would have a small fuse for "logic power" and one for "motor power".
Your window motors might use a PTC thermister wired i contact with the motor. They have to be sized right. See: **broken link removed**
This method really doesn't have the protections one might like to see. If a fuse blows, you won;t be able to reverse the motors without changing the fuse.
You could have a different fuse for forward than you have for reverse.
"Reverse biased" diodes should be placed across the relay coils.
Hey spec, wanna draw it?
Automotive quality relays could be used: http://www.omron.com/ecb/products/pdf/auto_glossaries.pdf
The Bosch relay datasheet is here: http://www.te.com/commerce/Document...DocNm=V23234-X0000-A001&DocType=DS&DocLang=EN
The coil is about 85 ohms, so 12/85 is about 140 mA. This may be too much for the tact switch to handle. We will have to work on that one. See: http://www.digikey.com/product-deta...switch-switches/1825910-7/450-1804-ND/1731414
which is rated for 50 mA, so the OEM DASH switches WON'T work!
An SPDT center off switch would work.
I can "fix" it so the OEM switch works, but really need to know how it is wired.
Take a look here: http://www.robmeyerproductions.com/bows.html at the first figure. I don't LIKE it, BUT it gives you an IDEA how things COULD be wired. In that diagram, the limit switches are INDEPENDENT which is not your case and the motor moves with a low current signal. Protection diodes are not in place either. The important thing is that the limit switches don't carry the full motor current. That wiring diagram SUCKS!
Your wiring would look MORE LIKE this
The "SPDT" Automotive relays are available in a dual configuration with plugs and wire leads. e.g. **broken link removed**
When your finished wiring the contacts, you have a relay for up and one for down. Because the motor is shorted with both off or even both on, the motor stops instantaneously.
Now, your choice if you want common + or common negative.
NO LIMITS yet. SUPPOSE the limit switches close on UP and close on DOWN and have a common terminal. So, you want to wire the limit switches so that they activate their corresponding small 12V DPDT relay such as http://www.digikey.com/product-deta...mfield-relays/9-1462037-9/PB1181CT-ND/1828471
So, with 12 V common to the small relay and the coils going to ground via the limit switch, we now have 2 independent contacts.
We wire one set of the independent contacts such that the EXTEND relay is not allowed to extend if the EXTEND LIMIT relay is activated. We do the same for retract. These little relays activate when they are at their corresponding limits and one of their SPDT contacts won't allow (Opens) the EXTEND or RETRACT signal to get through to the other relay.
So, we have a set of SPDT contacts left. We arrange these in parallel like an OR Gate, so you get a single contact that's closed when the motor is not at either limit. So, we can arrange the contact (direction and appropriate resistor) to activate the LED when the motor is somewhere in the middle.
We can ""play a game" and but a full wave bridge rectifier across the motor and power that LED from the motor power. Now if the motor fused blew (sized to protect) there would be no power to activate the LED when the spoiler is in the mid position.
So, you would have a small fuse for "logic power" and one for "motor power".
Your window motors might use a PTC thermister wired i contact with the motor. They have to be sized right. See: **broken link removed**
This method really doesn't have the protections one might like to see. If a fuse blows, you won;t be able to reverse the motors without changing the fuse.
You could have a different fuse for forward than you have for reverse.
"Reverse biased" diodes should be placed across the relay coils.
Hey spec, wanna draw it?
Automotive quality relays could be used: http://www.omron.com/ecb/products/pdf/auto_glossaries.pdf
The Bosch relay datasheet is here: http://www.te.com/commerce/Document...DocNm=V23234-X0000-A001&DocType=DS&DocLang=EN
The coil is about 85 ohms, so 12/85 is about 140 mA. This may be too much for the tact switch to handle. We will have to work on that one. See: http://www.digikey.com/product-deta...switch-switches/1825910-7/450-1804-ND/1731414
which is rated for 50 mA, so the OEM DASH switches WON'T work!
An SPDT center off switch would work.
I can "fix" it so the OEM switch works, but really need to know how it is wired.
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