on-off-on controls for an electric motor that can be executed remotely in 20' range

Discussion in 'The Projects Forum' started by rmbarger, Mar 24, 2011.

  1. rmbarger

    Thread Starter New Member

    Mar 24, 2011
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    I have a boat lift that has a analog switch for on/off/on motor reversing.
    I would like to build a black box to allow me to do those switching functions with a remote device. Any economical ideas. The electric motor is not very powerful.
     
  2. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    By remote do you mean a wired-remote?...an RF remote?...? A wired-remote...switch on a cable...should be pretty easy. Do you have a schematic or picture (the terminal side) of the current switch?

    Ken
     
  3. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
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    At what voltage does the lift operate?

    I would make a simple remote to turn it on, with a limit switch to stop. Then "off" or the next "on" would reverse with another limit switch to stop. The important thing is to have the limit switches hard wired and not dependent on the RF link. In other words, a garage door opener that can be bought used at a yard sale.

    John
     
  4. SgtWookie

    Expert

    Jul 17, 2007
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    Sorry John, but I'll have to disagree with you.

    Sometimes it's necessary to reverse the direction of the boat lift in mid-lift; for example if you suddenly noticed that you'd forgot to remove a dock line from a cleat, or a forgotten something on the dock got hung up on the gunwale, or maybe a fender hanging from a cleat got stuck under the edge of the dock. In such cases, you'd want to be able to reverse the direction quickly in order to avert/minimize damage.

    The lift direction control switch must be manned the entire time while the lift is in motion. The switch needs to be spring-loaded so that it will not stay in either "run" position without a human finger/thumb holding it.

    If it is desired to be remotely controlled, the control box should be hard-wired to a fixed junction box. The control box needs to be low voltage AC or DC, so in case it is dropped into the water, nobody will get electrocuted. It should not be controlled using a wireless remote of any type, as interference could result in inadvertent operation of the lift. Old electric garage door openers were notorious for inadvertent operation when located near radio stations.

    My initial recommendation is that NO modifications be made to the lift controls.

    Failing that, you should consult an electrician to ensure that any modifications performed to the controls are in compliance with NEMA standards, NEC codes and local codes for outdoor service.
     
  5. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
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    Well, then we will have to disagree.

    The OP has not presented any of those concerns, and I stand by my response based on what information is available. In your scenario, my concern is that typical Part 15 remotes can't be depended upon to operate a winch. If you know of such an application that does not use limit switches, please show it.

    John
     
  6. SgtWookie

    Expert

    Jul 17, 2007
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    John,
    I have never seen a lift, whether for boats or for automotive use, that could be set to run to a limit without operator intervention; someone had to be standing there, manually holding a button or valve down.

    It's been a long while since I've been an active boater, but I can't imagine that the safety aspect has changed. Every automotive hoist I've seen in the last couple of decades is still operated manually, and won't move unless someone is holding a control.
     
  7. bertus

    Administrator

    Apr 5, 2008
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