Powered side step question

[POPEYE]

It's nearing completion, what i've done is use a small winch to haul the step up and down, the winch dosen't have any relays as the up.down hand held switch works on the main (30amp) cable, what i'd like is some sort of current cut-out when the step reaches it's upper stops, probably the same when it at it's drop point but that aint so important as the cable will just unravel a bit but at it's top if the button is held in a tad too lond it's just gonna put undue strain on the cable and accoiated metalwork, knowing my missis this is just what will happen, if/when she opperates it her self (which was the plan)
can i do this? will i need to rewire into a relay to do this? i was thinking about a micro switch but once it shuts off current how do ya get it to go down again,
any idea's/drawings/thoughts, come and do it for me most welcome
cheer's
ps, i'll post some pics asap, been real busy with it, welding, grinding, and banging my head when i jumped up the pit steps and forgot the door was open

[slobodan]

Reclining chairs use micro switches. I would have also thought this was the way to go.
It'll only cut the power one way, allowing it to travel the other way until it hits the switch at the other end.

[BUSHWHACKER]

How long (in seconds) does the step take to raise/lower.
You could use a relay with a capacitor to give a timed power supply.
So it'll be press the button once and the step will raise or lower, a bit like the one-touch window switch on the driver's door.

[meooo]

I would think two 30a relays required and possibly use stop light switches as triggers (cos they're adjustable) Could you not loop the cable around the drum of the winch so it would slip instead of pulling the cable?

[POPEYE]

Thanks for the replys/ideas, i aint timed it Vince but guess it's around 10 seconds, not sure i could do the wiring that way as i've never used a capacitor, the chair type switching sounds a good idea, obvisiously the hand held switch "switches polarity to reverse the winch so yeah once powers been cut by the top limit switch pressing the down button should send it down ok and vice-versa for going up again, ok cheer's, need to get my thinking cap on and my pencil out, i have a couple of 40 amp relays kicking around i think.
not sure what you mean about looping the cable on the winch meooo
thanks again

[Vultch]

External microswitches are nice and the more accurate but they may fall foul of rain/crap/dirt etc

the timed option I think would be more reliable

e.g.

http://www.maplin.co.uk/universal-timer-kit-3315

this only handles 2A so you would need it to drive a bigger relay rated at your winch motor ampage

[BUSHWHACKER]

First diagram here.....
http://www.the12volt.com/relays/page5.asp#top

[POPEYE]

Thanks Vince/Vultch, look mates, sorry, give this a bit of thought and i think i/she will need full control of the step, so an auto set up wont be any good, the problem is we will need to stop the lift part way up so she can "manouver" her ass onto the seat, once shes in the sitting position (with her legs and feet still out the door and on the step we can than take the step all the way up, from that position she can then swing her legs/feet round and into the foot well,
i know all this sounds a bit awkward but please remember due to her haveing parkinsons plus several other things all her movement are pretty slow,
so if the step went all the way up in one go i just know she'd get in a mess and end up hurting herself,

ok so all that said, i think the best bet would be (as someone said i think) to use either micro switches or the adjustable brake light switch type thing, only prob i can see is sealing or water proofing them so water/ shoit dosen't get in,

i'm a bit stuck as to how to wire this, would i need a pair of relays? (one for the up power and one for the down, i think i have two 40amp relays in the box)
this is what i worked out so far, just not sure how to connect the thich 30amp leads, whats on there at the moment is one red lead comes from the supply (battery via a 30amp fuse) to the opperating hand held switch, anothe red lead comes from the switch to the winch, same set up for the black leads except one is connected to chassis, then to the switch and from the switch to the winch, so how do i run them to pins 30 and 85?
sorry its a bit long winded and thanks for any info,

should point out that the opperating switch i've shown in the drawing will prob be a pair of flich switches summat like light flasher switches, push to light and let go they go off,
you ever get the feeling your digging yourself deeper into a hole

[slobodan]

The reason I used the reclining chair similarity is because you have full control.
You can go up a bit, stop, up a bit more etc. you have a controller with 2 buttons on it.
I did have one in bits a few years ago and there was a Printed circuit board control thingy in there.
Maybe find a secondhand chair controller, If I remember it was transformed down from 230v.

[madcampbell]

Is there any way your wife could accidentally get her foot caught between the truck and the lift? or bring it down on her foot during operation?

At work we have an external lift that that has a sprung plate on the under side and the top edge that cuts the "Down" power when the lift either gets to the bottom or an object is trapped and sets it off (and the reverse at the top)

I don't know how you would wire or switch it, sorry. But if your doing it then good to put the fail safe in in case she slips using it.

cheers
Mark

[POPEYE]

Cheer's Mark/Slobodan, the chair switch idea is a goodun, unsure about getting hold of one or how to wire it,
Mark, she cant get her foot caught under the step as i have fitted bump stops to keep it off the deck a bit, as for going up it will stop about 5 inches short of the sill, it cant go up nay further as the back part will hit the chassis and thats well inboard and her foot cant reach in that far, plus the step will be in the outboard position (via the air ram cylinder), only when she in and seated ok can i/we retract the step, only other concideration is slipping, i'm gonna fit some grab handels on the door inner side and the pillar (between the front and rear doors) also i wont let het do it completly on her own, i'll be opperating it till she's confident enough and even then i'll be there in case she should slip, also be fitting some non slip covering on the alloy checker plate step top,

well i think that drawing i attempted is wrong, for a start i'd need two seperate low current feeds to each relay, not connected like i shown there, plus i think one relay would do as there is only really one positive supply (red lead) the switch over polarity is done in the hand held switch (than was supplyed with the winch, so i dunno, anyway for the moment i'll be opperating it for her so i can judge when to let go the button
gonna fit the controlls on the passenger door so i can opperate it and assist her at the same time, it'll be an air switch to pump the step out and the up and down buttons,
be a f##k site easier to flog the ba$tard and get a normal bl00dy car,
but then i go stir crazy

[BUSHWHACKER]

What you need to do is make the door open and the seat lower like Captain Scarlet's SPV.

[meooo]

I know you've used a winch/cable design now but....
Could a wiper motor, driving the threaded part of a bottle jack be used as a crank/lever to raise/lower the step?
It would have to act like a crank and be able to tilt in relation to the step, but would perhaps offer more control.
As for looping the cable just think of the steering chain on a steam roller or such, or the cable system on a window regulator...just a thought...

[rikm777]

this is a wiring diagram for a toyota e locker but you could wire your side steps in an identical way.This shows a DPDT (double pole double throw switch) which are a couple of quid in macro to switch polarity to the motor.Basically doing the same thing as your winch hand controller.The second switch is a locking fork position switch which switches your earth (or ground as our american cousins insist on calling it)between the two circuits to your motor.So when you apply your current to your motor it brings the step up to the required position.At this point(you would have to fabricate this arrangement) the step moves across the contact in your locking fork position switch which breaks the earth to that circuit.the step cant raise any higher.Moving this contact across has now made the earth for your reverse polarity feed to bring the step down.Again when the step reaches its fully down position it moves the contact back to its original position thereby breaking the earth to that circuit and reinstating the earth continuity to the first circuit.
i hope this makes sense as its a fairly foolproof and simple way to do it.the only tricky bit might be the arrangement to trigger the locking fork position switch.i ,ve not had to buy one of these as it was already built into the axle i was wiring up.i would think it would involve a basic arrangement of 2 small metal lugs attached to the step to physically move the locking fork position switch back and forth.This was a fairly common set up in old machinery.no relays or electronic control gear needed.old school electro mechanical simplicity

[POPEYE]

Hi richard, thanks very much for posting the diagram i will print it and have a study, i see there is'nt a relay(s) in there! wont the 30amp main leads to and from the motor burn the switch out a bit quick? i think i have a DPDT switch in the garage, but not sure about the "locked and locking fork" switches, would the likes or maplins or vehicle wiring products have them? this looks an interesting idea but forgive me if i appear a bit thick (i am) by asking questions , thanks again, ian