question about powering solenoids for kinetic sculpture project

Thread Starter

slatepipe

Joined Oct 2, 2017
23
aaah, sorry - it's been a few months since i've been engaged with this project (i actually broke my finger so had a cast on for a month so couldn't do much of anything) and i made the mistake of not rereading the previous posts, i just assumed i'd mentioned the hoists. apologies again.

the solenoids previously mentioned will be fitted onto the accordion and will be driven by the Crestron touchpanel and processor. the accordion will be fitted onto an old hoist from an AV system which was used to lift a plasma screen out of a cabinet.
it is one of these : https://www.liftchair.com/okin-betadrive-lift-chair-motor-w-white-moving-block-p35.htm

it's pretty much exactly the same, maybe a bit longer. one end of the accordion fits onto a plate at the end of the hoist, the other end of the accordion is fitted onto the moving block

but at the moment it only works with two hoists connected, if one is unplugged then the other connected one wont work

thanks for your reply, sorry again for any confusion :)
 

Thread Starter

slatepipe

Joined Oct 2, 2017
23
hi again, here's a sketch i've just drawn of the basic layout of the project. At the moment it works fine with two of the hoists, but i only really want to use one. i have some solenoids as well but i haven't got round to adding them yet, that should happen after i've sorted out this step

hope the sketch makes sense, many thanks for any helpIMG_20180115_195430.jpg
 

Thread Starter

slatepipe

Joined Oct 2, 2017
23
hi there - i don't have a schematic of the control box, i will have to email the company to see if they can help. in the meantime here is a picture of the circuit board i just took. the two big black wires go to a fuse on the right and you can see the 3 DIN socket inputs on the left. the top two go to the hoists and the bottom one is the control from the relay output on the Crestron processor

also - here is a short clip i made of a first test of one of the hoists with the accordion (the other hoist is on the floor) :

Thanks again
 

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shortbus

Joined Sep 30, 2009
8,816
With the explanation so far, it sounds like the hoist power outputs are wired in series. They should be wired in parallel. In series they both would need to be hooked up, parallel they would be independent.
 

Bernard

Joined Aug 7, 2008
5,788
How many wires go to the hoist ( linear actuator, LA ) ? I'm guessing 2; stops when reaching end of travel & changes direction with lead reversal ?
The LAs are 24 V so do not expect series connection.
 

Thread Starter

slatepipe

Joined Oct 2, 2017
23
hi again

I've been hunting around for schematics and at the moment have opted to contact the company that I think makes them and asked them for advice on running the setup with just the one hoist. So I await their (hopefully) positive reply

https://www.dewertokin.com/
 

Bernard

Joined Aug 7, 2008
5,788
2nd guess on LA; as its intended use is for used for positioning the 5 wires, might be 2 for motor, 3 for pot.
If you can obtain a matching DIN socket & add test wires. Extend LA to about 1/3 before un plugging from control so that pot will be unbalanced. The lowest resistance between two wires prob. the motor. The highest resistance will be ends of the pot, 5th is then the wiper. The LA might have internal limit switches to prevent over run. If all goes well, you can have manual control of direction or have automatic reversal.
 
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philba

Joined Aug 17, 2017
960
Or the 3 wires are for a quad encoder. Or just could be limit switches like Bernard said. All pretty easy to test for. A visual inspection under the covers could be enlightening. Given that it was just to lift a TV, I'd bet on limit switches. Do you have an original manual for the lift?

Not wanting to rain on your parade but the lift was probably designed with low duty cycle components. 10 years of use would probably see < 5K cycles, maybe 10K. Your robo accordion will probably see 5-10 cycles in a minute so, optimistically, 2000 minutes or 36-ish hours. Worth keeping in mind.

By the way, I think this is a cool project!
 

Thread Starter

slatepipe

Joined Oct 2, 2017
23
hi

sorry for my ignorance, i'm pretty much a beginner at this. linear actuator (LA) means the hoist which goes in and out? i figure yes :)

i've had a look inside the end of one of the hoists and there is a little sensor/switch which switches it off when it gets to the end, and i suppose there is another sensor/switch at the other end of the hoist to stop it crashing into the motor

i don't have an original manual for the hoist, hopefully the company i emailed above yesterday will respond, but i'm not holding my breath

enclosed is a photo i just took one of the DIN plugs which come out of the circuitboard box and goes to the hoists. it is initially an 8 pin DIN which converts to 5 pin DIN on the way to the hoist. you can see that 2 pairs of pins are wired together, or loop back to themselves, and 5 of the wires then go through to the hoist. I'm unclear as to why there would be 5 wires, as it only does two things - goes up and goes down

the duty cycle is how long it take to go up or go down yes? this takes about 30/40 seconds i think but when using the accordion i will reduce this to probably 15 or 20 seconds using Crestron code, or it would pull the accordion apart

i guess that when the hoists where in their original use to raise a screen out of a cabinet for a meeting then they would have only been used intermittently, ie - only when a meeting required the screen. but i have no idea how many times they would have actually been used

im guessing that there is no shortcut with the wiring on the DIN sockets to fool the circuitboard into thinking there are two hoists attached when i only need one?

i can see on the circuitboard (photo attached) there are some DIP switches - could these be relevant for switching between one or two hoists?

thanks again for all this help :)IMG_20180118_112816.jpg Okin Betadrive BZ circuitboard.jpg
 

Bernard

Joined Aug 7, 2008
5,788
The more that I look, the less I know, but pretty sure that there is no position sensing, pot . The lift chair LAs
I've seen on the net have 2 cords, one power other control with 5 pin DIN. The folded back wires might be an interlock to requite both LAs to be plugged in to operate.
The duty cycle is the time that motor runs compared to time that the motor is off.
DIP SWs, another mystery.
 

shortbus

Joined Sep 30, 2009
8,816
i can see on the circuitboard (photo attached) there are some DIP switches - could these be relevant for switching between one or two hoists?
From working with stepper motor drives, I'd be willing to bet the dip switches are for choosing a current limit for the LA's. They, companies, doing things like this sometimes make one controller that will work with many motors. Doing that makes their costs and part numbers smaller for the company.
 

Bernard

Joined Aug 7, 2008
5,788
With 8 pin plug at control box, with 2 pairs shorted & one open that leaves only 3 wires to LA which leads me to believe that LA is a conventional motor
reversal with polarity reversal; 3rd wire ?
Might try putting 2 jumper wires into socket to match jumpers in plug & see if other LA runs ?Linear Actuator 00000.jpg
If in testing & there is miss guessing then sparks may follow ?
 
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philba

Joined Aug 17, 2017
960
Until the TS opens up the actuator and traces out the wiring we won't know for sure. At this point, though, it's clear there are limit switches. A TV lift usually has 2 positions - up and down. The limit switches take care of that. A manual would confirm it. No need for steppers and they'd be too slow anyway. Looking at the controller box, it clearly uses relays probably 2 per h-bridge. Pretty old school. I doubt it's anything sophisticated.

3 wires need for 2 limit switches com, top, bottom.

The dip switchs could be a network address thing for the crestron system or other configuration issues.
 
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Thread Starter

slatepipe

Joined Oct 2, 2017
23
hi again

well i found two more email addresses for the company in Germany and forwarded my first email to those as i didn't yet get a response from teh first email i sent, so i'll have to wait and see again

i don't think the DIP switches are for any network or Crestron issue, i think the motors have been adapted to work with Crestron in their original setup. The setup I am currently using for this project is definitely adapted for use with Crestron. The control box came with a rocker switch on a cable which made the hoist go up-off-down depending on the rocker switch's position. I was able to cut off the rocker switch and fit the bare wires into a phoenix connector which then attached to a relay output on the Crestron processor, which then allowed me to write code to control it from the touchpanel

I also think (though obviously i'm a novice and could be wrong) that the DIP switches aren't for limiting the length of travel of the hoist as there are limit switches at the ends of the bar that it travels along which stop it

"Might try putting 2 jumper wires into socket to match jumpers in plug & see if other LA runs ?" I tried using a jumper wire in one of the other DIN sockets from a spare motor (i have about 4 which i can potentially use) last week, but due to my lack of knowledge i think i broke the circuit board. I put the jumper wire in the two holes which together gave a 26v reading. sorry if that is making people cringe :)

i've just taken the cover off the motor (this is the actuator right?) and made a note and taken a photo of the colours of the wires and where they go. hope this helps

yellow - red. DIN into motor
red - blue. DIN into motor
green - black. DIN into motor
black - green. DIN into motor
brown - blue. DIN into limit switch in arm
black - yellow. motor into limit switch in arm

hopefully this will make things a bit clearer for some people, or maybe it'll do the opposite

thanks again for this amazing help

wires.jpg
 

shortbus

Joined Sep 30, 2009
8,816
Not to be mean about it, but it seems like you would rather we waste time trying to help you, rather than looking up the manuals for your controller. We don't know the model you have, but you do. I looked up the page on the manufacturers website for you, but you still seem to want to wait for an Email that may never come. I don't understand? And again NOT trying to be mean, but many people have been trying to help and you don't seem to want to help yourself. Hope I'm wrong in saying this. It is your project after all, so do what you please.
 
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