Questions - Help - 3DOF AC Platform IT Begins -

I did and it gave me 470 minutes or so trial time ... So after learning it ... sketching one or two drawings ... it goes off .
I'd like rather upload a cad file that doing so .

Hello again Speedy,
Wow. Thanks for the very detailed drawing.
Correct me if I'm wrongs here.
1. TWO push-button switches, PER Gearhead, one to reverse at top of stroke (If gearhead goes past 180 degrees) AND one to reverse at bottom of stroke (If gearhead goes past 0 degrees) ?
2. These push-button switches are normally open, closed if gearhead goes past the 0 or 180 degree on axis.

I'm going to do a "mock-up" of my motor placements and post a picture - showing pots and crankarms - let you folks see if I'm making a mistake / or / need to modify. After I get these in a
mounted, solid and stable position on the platform base - then I'm going to have to come up with some type of "fixture" to hole the switches.

Thanks - I have saved the drawing to my "build pictures" folder - named the pic "Speedy's Limit Switches"......

Tom

PS - I understood that the SketchIt Program was completely free...My Bad!

Correct but there is a big deference between limit switch and the push button ... they are made with a lot more acurate and spics ... life saving switches you can say ...

plus limit switch are two way "electrically " always closed on some direction ... Normally closed for a default direction [Common & ON1 ] ... then ... if motor is OFF working area then [Common & ON2] ...

Speedy,
Thanks for the update and information.

Tom

Awe yes @eaorobbie , I forgot to mention a safety (panic) switch. I don’t use one but I really should since I am not using limit switches either! Definitely good advice!

At first I was using 2x50 sabertooths with my first build. While testing and getting everything properly setup I had several instances where my motors went out of control and ended up in a high amperage stall situation. The sabertooth controller is designed to shut down before this situation destroys it. However, the 2x50 had a design flaw (which is why it is no longer available and replaced by the 2x60) with the motors terminals connector. It would short out under high current and destroy the unit before the shut down happened or by not allowing it to work. I destroyed two of them. In fact, one of them actually burst into flames. Without a dual controller replacement option for 50 amps available yet, I agreed to take 4 syren 50’s instead. I had several more high amperage stalls with them. While they weren’t completely destroyed, I noticed that on the large capacitors for the h-bridge, the caps were bulging. Upon testing them further, while they still functioned, on 3 of the 4, the maximum voltage output could no longer be achieved, so it did in fact damage them also. Now I am using the sabertooth 2x60. And while I have had a few stall conditions on them also, they are performing beautifully and work as described. DE traded out my two 2x50’s for the four syren 50’s. And on the three of the syren’s that were compromised, they gave me an RMA to send them in although I haven’t ever got around to doing it. So even though I had a lot of problems with their controllers at first, I have become a huge supporter of them because they took care of the problems without a hassle, and the 2x60 sabertooth is magnificent!

So anyway, back to the limit switch panic button topic. I now have been relying solely on my sabertooth’s to save my controllers, wiring, etc in stalled situations. It could still be dangerous in other situations though so I should put on a safety switch. But the problem I have with limit or safety switches is that I use extremely high current. I tried using two 100 amp 12 volt relays (one for each of my sabertooths), and while they did work, they got very hot and also lacked the rating to handle the 120 amp peaks the sabertooth can deliver so I took them off for now. I seemed to be getting a power loss also at high current draws thru them.

But to finally get to my point. My observation @cthiggin , is that you will not be using extremely high current. At 1 hp and 115vac you will probably draw only 10 to 15 amps maximum per motor. Therefore, finding limit switches that will work with your current should be fairly easy. In fact, while they may be too big and ugly for you, simple household light switches for $1 each should do the trick. And these could be wired in between the VFD and the motors themselves. Therefore, it wouldn’t matter that the VFD takes time to shut down. The only problem I foresee is if this might damage the VFD. However, a single safety switch that shuts off all the motors at the same time would need to have a much higher current rating than a single limit switch in your case. That’s the way I see it anyway. By the way, the limit switches would be in a normally closed position to allow your motors to work until they are opened. I think that's what speedy was saying also.

Hi BlazinH,
Wow - the "saga' continues. BTW, from all the info I obtained on the MicroMax Motors, 3 phase, 230VAC, maximum draw under load is 8.5 amps / motor-gearhead. Compared to what you guys are pumping out,
I'm about 90 amps LESS.....guess that's a good thing.

When I get to that point, hopefully soon, we must have, what I call a "Come to Jesus Meeting", and you all tell me what I need to do. Speedy provided a wonderful schematic, BUT, I just have to figure out how
to mount the rascals.

FYI to ALL - Over the past three years, I've looked at so many "AC Platforms" that I cannot count them, NOT just the CKAS... NOW, help me out here:
I have ONLY seen the PANIC BUTTON type on top of platform, near the occupant - I have never seen the "Kill Switches" on the gearshaft area that you folks are speaking of...again, I've learned something (Thanks Speedy).
WHAT do the professional manufacturers' use???

Thank you friends...it won't be long until I start the "mock-up of motors", and then the super team must "keep me out of trouble".

ALL have a most blessed one.

I guess I overlooked or forgot you are using 230 volts, not 115. That's even better for low current yes. But I'm in the same boat as eaorobbie on high voltage AC. Very Dangerous and life treating! But I'm sure this has been in your consideration already with the grandkids and all! I have been shocked many times with 115vac and it's a bi.ch, but I'm still here. I don't know if the same would hold true for 230 because I've always been careful and afraid enough of it not to have been! I guess with 230 though you will be able to run everything on one circuit?

Hi friend,
YES - I'm highly aware of 115v/230v - it will kill you in a heartbeat or less - Yes, I've been hit quite a few times in my life and it's not fun........THE HARDEST I've been hit was building a souped up
engine in the early 70's - Put a high capacity coil in, 70000 Volts, and it literally knocked me back and threw a wrench out of my hands. My arm and shoulder hurt for hours......thank gosh it was DC.

NOW, I've got to be very very careful - have a PaceMaker, just to keep my heart rate at a minimum of 60bpm - It was getting down to 43 resting.......just too low - heart is strong/fine/no blockages/ and
even as a kid, it ran 55bpm resting......new Doctors would ask if I was a "runner" - told them yes, to the coffee pot. So, in summary, must be careful - 8 years ago it was 43,000.00 for the appliance & 50 minutes surgery - can't afford a new one at this time.

YES, I'm going to run terminal bus's for the 4 incoming 230V wires - from there of course, to the VFD's - will split off and use two wires & a ground from the buss's to pick up 115V for accessories, etc.
I know I'll have to put a low-volt power supply in for the boards - just don't know what at this point. - Overall incoming circuit will be 230V, Single Phase, 30 or 50 amp circuit.
The plug will come out of my MainPanel and the breaker will be turned off - only time on is with the sim operating. All my components will be inside a well protected case, acrylic top, and will not
allow anyone to get close to the power.........SAFETY FIRST.

BTW - 230V will knock you on your crack - been there once and it was enough for a life-time.

I’m sure you're planning to have an electrically grounded frame as well? Since it is current that kills, not voltage, you would initially think that the less current your motors take the better. But it’s the potential you have to worry about which it sounds like will be a minimum of 50 amps at 230vac or 11500 watts (You will get more current before the breaker disconnects though unless you're maybe on a GFI but it probably wouldn’t matter at that current anyway). I think with the coil you mentioned you meant 70000 volts, not watts. If it were watts, I’m pretty sure you would be toast, literally. To get 70000 watts out of 12 volts would take a current of 5800 amps. But when you step up 12v to 70000v, in trade, you are taking away the amperage. So really is should be, “Thank gosh it was almost all voltage and almost no amperage”! It takes as little as .5 amps DC and .3 amp AC across your heart to stop it. The resistance in people bodies varies but it would take more amperage going into your body than that though. Amp for amp AC is more dangerous then DC. Here is why:

Hi BlazinH,
Yes, I meant 70,000 DC Volts - not watts...I corrected the post - I'll never forget the reaction.. - Thanks
Frame will be grounded. Take NO chances.
My Dad was a Master Electrician and he told me - AC holds on to you because of the alternations - DC knocks you away....gives you another chance.. Sure loved my Dad.
Thanks so much for the overview - can never forget to stay in review on this matter.
Have a blessed one,
Tom

Guys Don't worry about being shocked by electricity ... the three phase motor cable which will carry a 380/440V will be secured with plugs and fixed joints ... current consumption will not exceed 10Amps for the three motors + total project .

And the limit switches will deal only with the direction signal "24V " ...

Plus I cam up with something more ... Guess what ?

I remembered that how motors of my simulator was not moving ... even if every thing looks OK and that made me wondering for a while ...

And found that one of the direction wire coming from the limit switch to the VFD was not firmly tightened then problem solved ... So If we can disconnect the direction signal whenever we want ... VFD's will consider that a stop condition .

So here is my suggested additional Panic Switch connection ... down there "the red small switch in the next picture " sorry there was no room to put it full size .



here are some Decorative/Industrial examples of a Panic, Kill, Emergency, Stop ... switch .


Edit: Question ... How we are going to use one switch for a three VFD's?

Hi Speedy,

THANKS friend. Those are the type of "Panic Switches" I've seen on most of the professional ones over the past three years.

As I asked in post#106, What do the professionals use - I've never seen even one using the STOP Switches on the lever arm as you have outlined.... IF they were using internal encoders on the motors, would
this be the way they are doing it??? I'm reaching here, as again, I'm in an area that I know minimal about.

Speedy, just due to mounting issues ,(am I am NOT there yet - but looking and speculating), I still like the idea of one KILL SWITCH mounted beside me on the platform top. I know you said it would take
two seconds for the rascal to stop by using only this method, but "me thinks" that would be ok......AGAIN, "me and me only, thinks".

You're a blessing with your expertise and excellent overviews.

Tom

Tom ... I'm very Shocked right now ... Wait a second please ... you have a Pacemaker ?
and you are a good wilder ?
and you want to use VFD's with AC motors ?
I know you're very aware of what you're doing ... And this is not getting into personal information ... please I want you to consult your cardiac doctor for this project ?
Safety First My big good friend ...

Please inform with results if possible here in this page .

Don't make me use my right to press this ...

Hi Speedy,
I "sure do" have a PaceMaker - for last 7 1/2 years... It is NOT a defibulator, it ONLY keeps my heart rate at a minimum of 60bpm. I was running at 41 to 43 bpm resting, and the doctor said at that low,
I could have atrial fibrulation, which was not deadly in itself, but when the top chambers get out of time, you can have a pooling effect, that can cause blood-clots, which can be deadly.
I don't even know it's there - other than having it checked every three months....I am not on any blood-thinners or any other changes in lifestyle.

The ONLY restriction I have - I cannot have an MRI as the machine and it's powerful magnets would literally pull the pacemaker out of my chest - and I cannot go through a regular airport
scanner (the magnetic type)............I get the ol' pat-down..

Microwaves are no problem / Mig Welding is no problem, which used to affect pacemakers. (Checked with cardiologist before I started welding again and he said it was fine)

I sure do have every intention of running this platform with AC/ & VFD's - I will call my cardiologist and double check - AND I will email the manufacturer of the VFD's I plan on buying to see if there are any restrictions or "Hazards".

Speedy, THANK YOU for your concerns. I never thought one time about the different frequencies being output by the VFD's - Appreciate your concern and taking care of this ol' guy.

Have a blessed one,
Tom

BTW - IF my existing pacemaker STOPs for any reason, I will NOT die. My heart rate will return to 43 bpm (or somewhere in that range) - and I will feel very tired...
The NEW pacemakers at todays' date are somehow shielded - You have no restrictions - MRI's are ok - airport security is ok to go through - it's like the pacemaker doesn't exist -
When it's time for mine to be replaced - when batteries are at 25%, (they do NOT just replace batteries) - I will get the Latest / Greatest.

wooff ... breathing again ...

That is a very good peace of information ... zero knowledge for me into that .
Sorry if I was out of line .

@cthiggin , maybe bring the cardiologist around for a play on the sim once its done.

@speedy - No sir, not out of line - we need to be cognizant of the "human side" of our friends here. They hurt, we hurt...that's what "givers do!"....
and Speedy, it's appreciated - something that I will check into - JUST to be SURE! Thanks again!

@bsft - My cardiologist is a nice guy. He's a Brazilian, named Jose' Escobar - first time I met him, I said that name sounds like a "Drug Lord's" I saw on Miami Vice in the 80's - (100% true) -
He wasn't too amused. I also asked him that since I was paying him, could I call him Jose', he said no, call me Doctor..... AND, he's too much of a weinie to get on any type of simulator -
He just plays with EKG's too much and likes running the wire up peoples' legs and into their heart - AT 16,800.00 US a "pop"......on Tuesdays and Thursdays, he does a minimum of seven, EACH
day. "ME" in the wrong profession! (One of my customers had this procedure and 2 stents put in, he showed me his bill and with the stents, it was 73,000.00 US and some change)

Have a blessed one guys!

Tom

God bless you Tom ... what a perfect description of a Vampire .
poor people will go first to heaven , Why ?
They have nothing in there bank account if any that can not be explained when God ask them ...

Where/why did you get that ... and ... where/why did you spend it ?

Sleep well ... Have a nice day ... Back to work ... Enjoy the ride with us .

Hi Speedy,
Yes, you pretty much summed it up..."me" don't have to worry about that part of the conversation with God.

I have had a great ride with you guys from day 1.

Have a blessed one,

Tom

Hi to ALL my Friends,
Well, didn't go to church today, bummer - wife and I both went to a Pri-Med today...tried yesterday, but they were closed on Saturdays'. Just didn't want to wait until Monday and try and see our regular physician.
Both of us still feel like crap and just coughing out heads off, but a dry cough - nowhere as bad as the bronchitis - Well, we BOTH have "Walking Pneumonia", which is going around in our city at a pretty fast pace.
We "each" got two JUMBO Steroid Shots (they're Good!), some type of anti-biotic shot to jump-start our recovery and lessen the cough - PLUS a jumbo size bottle each of Antibiotic - and a "super-size" bottle of cough syrup - Can only take at night since it knocks you out and lets you sleep - SO, tonight should be a good one - Doc says about 4 days and well start really feeling better - about 7 days and the cough will be gone.

ENOUGH PERSONAL STUFF - My justification for my personal overview - I HAVEN'T felt like working on the motion sim....(humor me here?)

HELP AGAIN!
Attached is a pic and info of the pots I have purchased for the gearheads - Simple ?? - What type of "connectors" are used on these type of male terminals coming out of pot???? I've looked and not found
them or even what type they are called.

Your continued help would be appreciated.
Have a blessed one,
Tom