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Numbers for SPDT relay icons

Discussion in 'Automotive Electronics' started by BibaResto, Nov 27, 2016.

  1. Dr_Doggy

    Dr_Doggy Well-Known Member

    Aug 11, 2007
    I'm having no luck with getting continuity on the switch/relays and have no reason why this is the case. Do you have any thoughts on a different type of switch other than the Spal type one I've been using? You did say that the relays I have are the 'correct' ones?[/QUOTE]

    actually a relay sounds like a clicking sound....
    thats what i mean, i suspect your problem is b4 the relay, again volt testing helps alot here, by the looks of the photo you are using limit switches that came with it right??, if so then we should continue to use the ones intended ... an easy mistake i can think of is maybe the limit switches are hooked up reverse to the button switch ... but we can only guess right..

    ..... another problem is a switch could be shot....

    a way to test is to manually put the spoiler in to the 3 conditions of top middle and bottom(ie direct to battery for x time, as you did before),
    for each condition, use volt or ohm meter to test the condition of the switch..... so hook up meter to a switch , move spoiler up/down and get readings... one position will be different than others...

    by doing an ohm test you dont need to feed battery to switches, just clip the ohm meter red and black wires to each side(node) of the limit switch

    you can also ohm test to see if the main switch is passing energy when you flip it...
    Last edited: Dec 4, 2016
  2. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

    Oct 30, 2010
    I definitely don't have the time to do the totally automated version, but it would at least be nice to know about how LONG it takes to deploy.

    I have a hearing issue at 2600 Hz. Tinnitus. It just so happens to be at the frequency of a lot of buzzers. There's "supposed" to be chime only when you manually retracting and it's done.

    1. So, there is likely no components on the other side like a chip resistor? This is expected.
    On your new meter, hopefully, you have a range that's marked with a diode (continuity tests).
    In this function, the meter beeps if the leads are shorted.
    Use that function and measure the LED in both directions. I'm expecting nothing (overrange) and something around 2 V)

    2. So, your switch has two wires. Put an ohmmeter on those two wires and tell me the resistance:
    When pressing UP? (expecting close to zero)
    When pressing Down? (Guess: Something between 200 and 1500 ohms)
    Not pressing anything? (expecting overload) e.g. +1

    We have to deal with this separately.

    The limit switches are, sort of, backwards in sense and from what I think i read on the xfire forum, it's possible that the spoiler gets really confused under a low battery condition. That's something I'm aware of.

    There needs to be secondary protection too: At this point it could be an ebay module, a properly sized fuse, a PTC thermister mounted on the motor or a combination.

    An idea of how much current it draws would be helpful. Even if the motor is running with no load.

    The current school of thought would be to try to:

    1. Use the wierd switch
    2a. The RED LED would indicate not at either LIMIT
    2b. Replace the LED with a 2 lead bi-color one and with some electronics
    make it glow RED when fully retracted and GREEN when fully deployed.
    3. Switch would move the spoiler only when pressed. You have to hold until:
    3a. The RED LED goes out .OR.
    3b the NEW LED turns GREEN when fully deployed or RED when fully retracted.
    4. Some additional motor protection mechanism
    5. Avoid spoiler movement during low-voltage conditions.
    6. Diodes have to exist on the relay coils

    I'm not too comfy with push momentarily for a full deploy and push momentarily for a full retract.

    I might be persuaded, if it's not too difficult to do:
    100a.) You must hold to retract with the 2a or 2b option.
    100aa) Much harder - If you let go before it's retracted, it extends fully like the OEM spoiler.
    100b.) Deploy is automatic meaning --> a momentary press deploys the spoiler fully.

    200) Chime: I did locate a reasonably priced chime, here: https://www.floydbell.com/products/specifications/CH-V09-525-W(S) The sound is listenable on the website. The Chime is off the table in the first pass.

    300) Malfunction: if it turns out to be needed for some reason. Options at this point are:
    8a) RED LED Blinks.
    8b) Single Bi-color LED turns Yellow (What this means is it turns RED and GREEN really fast making yellow)

    500) Not likely a full blown PCB at this time. (breadboard style).

    My Preference (If I were a user): Single LED turns RED or GREEN. YELLOW for malfunction, if needed.

    100) The choice of color functions of RED/GREEN is due to the fact that over 63 mph, the spoiler should be deployed, so green is go at all speeds. RED means - don't exceed 63 MPH.

    EDIT: Renumbered
    Last edited: Dec 4, 2016
  3. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

    Oct 30, 2010
    relay: (We have to wait until you get your multi-meter and take some really baby steps here)

    From the other post;


    Understand the relay
    I'm assuming the relay diagram is on the relay. It might not be. Watch out for views: Is it viewed from the bottom or the top?

    Using polarity conventions:

    Baby step #1, assuming one relay and a (motor or a lamp).
    Identify the coil: Measure it with your ohmmeter. It should read a few hundred ohms between terminals (88) and (85)

    Identify the common terminal (30) and the NC terminal (87a). You should read close to zero ohms between these two terminals. Leave the ohmmeter connected.

    Connect the battery between 86 (+12 by convention) an 85 (Ground by convention)
    The relay should click. Feel it. Listen to it. The ohmmeter should read open.

    Move the probe from terminal onto terminal 87a to 87. That should now read a short.
    Remove the power from the coil (one side) and those terminals should open.

    If the relay doesn't work - STOP.

    Test the other relay in the same manor.

    Test your switch

    With a typical SPDT momentary switch (layed out as [1 2 3], the center terminal (2) in this case is the common terminal. If it is a bat handle toggle switch, follow the end of the bat to the back of the switch, so if the bat is on the (3) side, pins 1 * 2 are connected. Check this with your ohmmeter. When, you flip the switch, 1 & 2 will be connected.

    Hopefully this checks out too.

    Let's make this sort of system switch the positive voltage.

    Don't connect to +12 and ground to the power source just yet, Just label them as such.

    So, let's connect +12 to the common terminal of the switch and to terminal 86 of both relays. If you made a connector that daisy chains use that connector.

    So, you will have the center terminal of the switch, the +12 supply and pin 86 of one or both relays all connected to +12. Connect pin 85 of both relays to ground.

    Before we connect power, lets verify stuff is connected properly. With nothing connected to power, Put the ohmmeter where V+ and ground would go.

    You switch should indicate a few hundred ohms when in either extreme and OL in the center.

    Remove the ohmmeter and Connect power.
    Flipping your switch should make one relay click, both be off in the center and the other relay should click.
    When one relay is on, the other should be off. Terminal 87a will have continuity to terminal 30 of one relay and terminals 87b and 30 will have continuity of the other relay and vice versa, when your in other than the center off position. When the switch is off, 87a and 30 will be connected together.

    I'll choose this turn.

    OK, turn off the power and now connect pin 87 of BOTH relays to ground.

    Put your ohmmeter between the two terminal 30's. It should read nearly zero.

    Apply power with the ohmmeter still where it is. Momentary one way, OL (Overload) and the other way OL and the center , shorted.

    Remove power and put the DVM into volts mode to potentially read +12 V.

    Connect both terminals 87 on each relay to +12 Volts. Apply power.

    In the off position, the voltmeter should read zero. In one direction aprox 12 V and with the switch in the opposite direction -12 V.

    Your ready to connect the motor to pin 30 and 30, the common contacts.

    The motor should move in one direction and then the other and stop immediately when in the center. For the system to work, both relays have to work.

    The wires going to the coil can be lighter than the wires going to the motor. The wire from 87a to 87a should be short and then it can be returned to ground.

    In the final game, a single (1N4001 to 1N4004) diode should be placed across the coil terminals of 85 and 86. The band on the diode would go to the + voltage. These could be easily soldered to the relay terminals.

    So, instead of hooking things up and see if the magic smoke comes out, hook it up piecewise and troubleshoot along the way. You can substitute a lamp for the motor in all but the final test, but it won't show any difference for the change in direction.

    So, very simply, the relay holds both ends of the motor at ground when unenergized. The CW or CCW relay just connects one of the grounded wires to +12 making the motor rotate in some direction. Stopping the motor, means the motor acts as a generator into a short and it stops quick. Trying to make it go forward and reverse at the same time is the same as braking.

    The limit switches in the OEM spoiler have the wrong sense. Closed at a limit, rather than open at limit.
    In a design of this type, the "close signal" would be "removed" when at the "closed limit" and vice versa.

    The remaining reminder is that not all automotive relays have the same pin out. If for some reason, you accidentally put the relay coil in series with the motor, the relay would be toast.
    Last edited: Dec 5, 2016
  4. dave

    Dave New Member

    Jan 12, 1997

  5. BibaResto

    BibaResto Member

    May 23, 2016
    Irwindale, CA

    BRSpalSwtchB.jpg BRSpalSwtchA.jpg BRBoschRelay.jpg
    I started this a while back, but I've been under the gun to complete the restoration of a client's car which really limits me for the next few weeks.

    3rd paragraph from the top - 88

    The relay's check out fine.

    6th paragraph - I don't understand.

    Test your switch

    1st paragraph - I've been asking you to suggest a different switch from my Spal type (see below) one. What type are you suggesting?
    Since I have no control where the photos will be located Spal info: Top post is D; row 2 Lt to Rt. C, A, B; row 3 E, L. Continuity upper rocker: A-D, C-L; lower rocker A-E; center C-D, C-L; B-E. I'll certainly say that it is a very confusing switch. I've been strictly using A-D, A-E. I assume L is for light. I've been wondering if a DPST switch might work.
  6. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

    Oct 30, 2010
    Wow! getting somewhere again. SPAL is a manufacturer whose diagrams suck: https://webstore.spalusa.com/content/files/content/PDF/33040041_SPEC.pdf
    Your using a window switch. It's NOT a (on)-OFF-(on) switch by a long shot. It appears to be a DPDT center off switch wired internally to be a reversing switch.
    It also has a light for Illumination.

    It won't work unless you want to use the switch to drive the motor directly without relays. I suspect it will always run in the same direction, no matter which way it's pushed.

    I, sort of though we were going to deal with the weird OEM spoiler switch and I still need the resistance values for that.

    This https://webstore.spalusa.com/content/files/content/PDF/33040041_SPEC.pdf is a simple automotive SPDT (on)-off-(on) switch. The DPDT version will work too.

    So, with two relays, a switch and no limit switches connected, you should be able to make the motor go CW and CCW

    This a a mistake on may part. Should be (86) and (85)

    What DVM did you get? Can you link to a datasheet?


    You can use the tags [quote=] and [/quote] to quote passages. Use Other options/Preview to see what the post will look like.


    is typed as

    [QUOTE="KeepItSimpleStupid"]Baby step #1, assuming one relay and a (motor or a lamp).
    Identify the coil: Measure it with your ohmmeter. It should read a few hundred ohms between terminals (88) and (85)[/QUOTE]
  7. Dr_Doggy

    Dr_Doggy Well-Known Member

    Aug 11, 2007
  8. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

    Oct 30, 2010


    a youtube video on basically how two relays can control the direction of a motor. Note: The horizontal wire across the actuator isn't connected to the actuator or motor. The two wires at the bottom are the actuator motor leads.

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