logo elektroda
logo elektroda
X
logo elektroda

Wiper Motor System Connection with Left-Right Switch and Two Limit Switches

kana23 19413 18
ADVERTISEMENT
Treść została przetłumaczona polish » english Zobacz oryginalną wersję tematu
  • #1 16830933
    kana23
    Level 11  
    Forumers can I ask you for help in connecting the wiper motor system to the left-right switch (photo in the attachment) and two limit switches.
    I also attached a picture with the layout elements that I would like to combine.

    Thank you in advance.
    Attachments:
    • Wiper Motor System Connection with Left-Right Switch and Two Limit Switches text3036.png (27.41 KB) You must be logged in to download this attachment.
    • Wiper Motor System Connection with Left-Right Switch and Two Limit Switches 6f1e72339f73e200med.jpg (37.67 KB) You must be logged in to download this attachment.
  • ADVERTISEMENT
  • #2 16831005
    dioda1000
    Level 28  
    Describe how it should work.
    And try to connect if something goes wrong it will improve.
  • ADVERTISEMENT
  • #3 16831011
    kana23
    Level 11  
    The motor will be connected to the screw moving the nut. Limit switches are to stop the nut at the left and right end of the screw. And the left-right switch will control the engine.

    Would such a thing pass the exam?
    Attachments:
    • Wiper Motor System Connection with Left-Right Switch and Two Limit Switches textj36.png (54.73 KB) You must be logged in to download this attachment.
  • #4 16831032
    michalek1988
    Level 26  
    Maybe at the beginning, draw it yourself without the limits, and then include them. It will be easier for you to understand how it works.
  • #5 16831037
    kana23
    Level 11  
    ok, if I put on a switch like that, something will change?

    Without extreme I would submit it like this.
    Attachments:
    • Wiper Motor System Connection with Left-Right Switch and Two Limit Switches text30.png (24.28 KB) You must be logged in to download this attachment.
    • Wiper Motor System Connection with Left-Right Switch and Two Limit Switches indeks.jpg (6.15 KB) You must be logged in to download this attachment.
  • #6 16831072
    michalek1988
    Level 26  
    This is the same (in electrical terms) switch as from one post. They differ in casings. In addition to NO (normally open) and NC (normally closed) contacts, limit switches are also provided. You haven't used the latter in your diagram, think about why, what role it plays and what would happen if you connected in the way you drew. In which direction the engine will spin, which will happen when a nut reaches one of the ends. As a hint, analyze how the limit switches work, maybe you have some, e.g. removed from the printer and the meter, you can measure what happens in such a situation. Instead of giving the P / L switch, the PS may be enough for you with the switch and limit switches, then the motor, after receiving the voltage, would rotate to the left and then turn back. The direction of rotation would be constant, regardless of the starting position.
  • #7 16831111
    REMUR.
    Level 27  
    Analyze the limit switches.

    Wiper Motor System Connection with Left-Right Switch and Two Limit Switches
  • ADVERTISEMENT
  • #8 16831255
    dioda1000
    Level 28  
    Diagram of colleague REMUR. work :) . With a small 'but' the wiper motor draws a little more than 1A. So use a suitable diode. Limit switches also for the appropriate current.
  • #9 16831272
    Anonymous
    Anonymous  
  • #10 16831284
    dioda1000
    Level 28  
    Art.B wrote:
    Without any LEDs or weirdos.

    @ Art.B
    The engine has, for example, outside the window, how many wires do you need to control from the room?
  • #11 16831287
    Anonymous
    Anonymous  
  • #12 16831357
    kana23
    Level 11  
    The operator must be able to choose whether the engine will turn left or right. The system will not work often and long. The whole will be mounted in one room on one machine. Will the Art.B solution "without diodes and oddities work or do I have to have something else? Alternatively, how strong diodes should I use?"

    I have such ones: http://lispol.com/produkt/przelacznik-krancowy-mikro-z-dzwignia-18mm---80100
  • #13 16831367
    Anonymous
    Anonymous  
  • #14 16831459
    kana23
    Level 11  
    I think I'm starting to understand, I think :) is your schematic with relays to be connected as I have drawn it? I'm not sure if I did the right thing -.
    Attachments:
    • Wiper Motor System Connection with Left-Right Switch and Two Limit Switches 8725277800_1510993452.jpg (1.98 MB) You must be logged in to download this attachment.
  • #15 16831472
    Anonymous
    Anonymous  
  • ADVERTISEMENT
  • #16 16831503
    kana23
    Level 11  
    I corrected, please check. I have analyzed and understood the action.
    Attachments:
    • Wiper Motor System Connection with Left-Right Switch and Two Limit Switches qqq.png (51.35 KB) You must be logged in to download this attachment.
  • Helpful post
    #17 16831507
    Anonymous
    Anonymous  
  • #18 16831515
    kana23
    Level 11  
    Thank you very much for your help.

    Added after 2 [hours] 39 [minutes]:

    Can I power it from a 19v 3.5 A laptop charger? Will it be enough? I know the voltage is too high, but the engine will run a maximum of a minute.
  • #19 16832042
    Anonymous
    Anonymous  

Topic summary

✨ The discussion revolves around connecting a wiper motor system to a left-right switch and two limit switches. Users suggest starting with a basic diagram without limit switches for clarity, then incorporating them to understand their function in stopping the motor at both ends of the screw. The importance of using relays to handle the motor's current is emphasized, with recommendations for automotive relays and appropriate fuses. The author seeks confirmation on the schematic and inquires about powering the system with a 19V laptop charger, to which the consensus is to use a 12V power supply instead.

FAQ

TL;DR: Use two automotive relays, NC limit switches, and a Left–0–Right selector; a wiper motor draws “a little more than 1A.” [Elektroda, dioda1000, post #16831255] Why it matters: This setup safely reverses a 12V wiper motor, protects contacts, and prevents overtravel in DIY actuators.

Quick Facts

How do I wire a 12V wiper motor with a Left–0–Right switch and two limit switches?

Use a Left–0–Right selector to drive two relays. Put the limit switches in series with the relay coils so only small control current passes through them. Let the relay contacts handle the motor current. This improves reliability and reduces switch wear in continuous use. Automotive relays are inexpensive and well-suited. “Each of these three will work,” but the 2‑relay approach is best for longevity. [Elektroda, 266564, post #16831367]

Which relay terminals go where for reversing the motor?

Wire the motor between terminal 30 on both relays. Feed +12 V to terminals 87 and 87a on both relays. This establishes opposite polarities to the motor depending on which relay you energize, giving forward or reverse. Confirm your relay pinout matches standard automotive layouts before power-up. [Elektroda, 266564, post #16831472]

Should my limit switches be NO or NC?

Use NC (normally closed) contacts when using protruding mechanical end-stops. In NC, a broken wire or failed switch defaults to open, stopping movement safely. With NO, the actuator might not stop until overtravel occurs. “Terminals on NC contacts and not NO if end stops are protruding.” [Elektroda, 266564, post #16831472]

Do I need diodes, and how strong should they be?

Yes—include suitable diodes to handle the inductive load and protect contacts. The wiper motor draws a little over 1 A, so choose diodes and any suppression components rated for that current and expected surges. Also ensure your limit switches are rated for the expected current if they carry more than coil current. [Elektroda, dioda1000, post #16831255]

What current does a typical wiper motor draw here?

Expect a little over 1 A in this forum-tested setup. Size wiring, diodes, and contacts accordingly, and allow margin for startup surges. Keep runs short to minimize voltage drop. Always verify your specific motor since models vary. [Elektroda, dioda1000, post #16831255]

Can I power the system from a 19V, 3.5A laptop charger?

No. Use a 12 V supply designed for automotive loads. Overvoltage can overheat the motor, stress relays, and trigger violent stops at the limits. Choose a regulated 12 V source with adequate current capability instead. [Elektroda, 266564, post #16832042]

What fuses should I install?

Add two fuses: about 1 A for the control circuit and 7.5–10 A for the motor circuit. This protects small wiring and relay coils while guarding the high-current path. Place fuses close to the power source for best protection. [Elektroda, 266564, post #16831367]

How can I build an auto-reversing drive with just a push switch?

You can use a single push switch plus limit switches so the motor moves to one end, stops, then reverses. This keeps direction consistent on each cycle regardless of start position. It simplifies controls at the expense of manual direction choice. [Elektroda, michalek1988, post #16831072]

What’s the simplest working wiring if everything is in one room?

Several diagrams work, including minimalist versions without LEDs. However, if you want long, reliable service, pick the two‑relay solution so small switches only carry coil current and relays carry motor current. “Each of these three will work.” [Elektroda, 266564, post #16831367]

How do NO and NC contacts differ on limit switches?

NO (normally open) contacts close when actuated; NC (normally closed) contacts open when actuated. Use NC for safety so a broken wire or failed switch opens the circuit and stops motion. Match contact type to your mechanical end-stop style. [Elektroda, michalek1988, post #16831072]

What happens if I wire the limit switches incorrectly?

Using NO contacts with protruding end-stops can fail to cut power until after overtravel, risking mechanical damage. Choose NC contacts for protruding stops. Verify switch function with a meter before powering the motor to avoid surprises. [Elektroda, 266564, post #16831472]

Give me a quick 3‑step how‑to for the 2‑relay driver.

  1. Use a Left–0–Right selector to energize relay coils for direction.
  2. Put both limit switches in series with the coil circuit so they interrupt control current.
  3. Route all motor current through relay contacts; keep the selector and limits as low-current controls. [Elektroda, 266564, post #16831367]

Are my small micro‑limit switches OK for this project?

Yes, if they only carry relay coil current. The two‑relay design keeps heavy current in the relay path. If you wire motors directly through limits, ensure their current rating exceeds your motor draw plus surge. [Elektroda, 266564, post #16831367]

Any final check before power‑up?

Confirm motor leads on both 30s, +12 V on 87 and 87a, and NC wiring on the limits. Manually actuate each limit to verify it opens the coil circuit. Only then apply power with the selector at 0. [Elektroda, 266564, post #16831472]
ADVERTISEMENT