Power wheels - dual 12v motor upgrade

[pblaze725]

I’ve been busy too but I went out to that garage and checked a few things out.
So here’s what I’m working with:


The brains behind this is a Weelye RX19
The normal model is for 2 motors but this one is setup for 4wd.


During basic operation the power to motors sends 12v and around 4amps if I’m measuring correct.






But during modified operation I unplug the power to motors and connect it to a Warm 89564 winch relay switch.


18v Milwaukee power then goes thru a motor speed controller, the relay and then the motors.




I went with the warm switch because the grounds from both circuits are separate.





One problem I’m having is as soon as I connect the ground to the relay switch (center tab) it connects and starts to get warm it works for a while and then something smells like burning circuits.

I hope this clears up what I’m trying to accomplish.
After I get the bugs work out for this system I want to duplicate it to convert this into a 4wd.

 

[Fordum]

That helps a lot. Couple of questions.
First, you say when you hook the ground to the center spade term, the relay connects.
Is that with nothing hooked to the other two terminals? It should not do that if the connection diagrams are correct.
If its connecting with the other two wires hooked up, then one of them is hot when it shouldn't be.

Second, when the Warn unit connects, does it click? I'm assuming that there are some small high power relays inside. If its solid state, we may be running into a voltage problem. But I don't really think its solid state without more heat sinking then it has.
Not sure if the Warn unit is supposed to get warm or not. If its relays, I would not think it would get too warm.
Check to see if the burning smell is coming from it or your speed control.

Meanwhile I will ponder on it some more. Rampage, are you pondering what I am pondering?

 

[rampage]

That helps a lot. Couple of questions.
First, you say when you hook the ground to the center spade term, the relay connects.
Is that with nothing hooked to the other two terminals? It should not do that if the connection diagrams are correct.
If its connecting with the other two wires hooked up, then one of them is hot when it shouldn't be.

Second, when the Warn unit connects, does it click? I'm assuming that there are some small high power relays inside. If its solid state, we may be running into a voltage problem. But I don't really think its solid state without more heat sinking then it has.
Not sure if the Warn unit is supposed to get warm or not. If its relays, I would not think it would get too warm.
Check to see if the burning smell is coming from it or your speed control.

Meanwhile I will ponder on it some more. Rampage, are you pondering what I am pondering?

I’m not pondering anything until I look at it tonight. Just skimming through it for now.

 

[Fordum]

Dang I feel old. Of course, it was a reference from way out in left field and really had nothing to do with the subject at hand.
But I thought you might get it.
Does the word "Narf" help?
If not, you have really missed out.

Also, you want to make Pblaze slap his head? Let him check out this link.

https://www.amazon.com/Milwaukee-Ba...d=1&keywords=B07Q71H57D&qid=1589073648&sr=8-1

I got it from this youtube link.

That model car does not have any real electronics like Pblaze's does. Which is why it works without burning something up.

 

[pblaze725]

Yes and yes to Fordums questions.

when I attach the ground to the switch part of the winch relay it makes the relay click.

the posts for the power to motors both measure 12v but no ground with power on but not driving.

Measuring across the 2 posts-
when driving forward the posts are 12v +
When driving reverse the posts are 12v -

it looks to me like a switch on the circuit board connects a ground to the circuit depending if you want forward or reverse.

 

[rampage]

Don't get the Narf reference.
I do like the battery dock holder. I need to see if they have one for my DeWalt so I don't have to make my own.

The last pic that shows the circuit board looks like the 2WD version (RX23) you pulled from the internet since it only has 3 connectors instead of your 4.

First pic you have labeled as 40amps and 100W, but below it says 4amps. I'm guessing that's 4amps to each motor since 48W + 48W is close to 100W. Not that any of that matters since we are only using the RX19 to power (what i assume) are a couple solenoids. I couldn't find any schematics for the internals of the 89564 so I'm only taking an educated guess at how it works by the wiring diagrams I saw. Did any instructions come with it?

Is that the same speed controller as the one in the video that Fordum posted? They showed the connections in there so just wondering.
And before I call it a night ... DON'T apply any power to the circuit you have set up!
I'm surprised you didn't release the smoke in the RX19.
I'll draw up a diagram tomorrow night ... (edit: I guess that would actually be tonight )

Oh, you do get bonus points for the blue Sharpie.

 

[Fordum]

I do like the battery dock holder. I need to see if they have one for my DeWalt so I don't have to make my own.

They do, scroll down on that page.
They also show a heavier version of the Milwaukee dock that might do better for Pblaze or anyone else wanting to power something with a Milwaukee battery.

I agree that you can find schematics for a hydrogen bomb easier than for that switch. It seems to have solenoids in it, because it clicks.

I'm tempted to buy one and cut it apart.

I know how the motor that the switch is supposed to run should be wired, and even though we are not using the switch like its supposed to be used, it should work....
I'm going to post some schematics in the next post to either completely confuse the issue, or make sure we are all on the same page even if its wrong.

OH, and the pondering and NARF is a Pinky and the Brain cartoon reference. Great show.

 

[Fordum]

OK, here goes:
The first part of this I am fairly confident is correct. I have wired many of these winch motors, and this is how they work. Since the Warn switch is designed to run a three terminal winch motor, it should at least resemble what I am about to post.
First, here is how the three terminal winch motor is wired for forward and reverse.


Note the "A" and the two "F" terminals swap connections.
Now, remove the "A" terminal, and hook the blue wire to negative, and you have what Pblaze has. The Warn unit is simply swapping the polarity.
If it is simply using solenoids, it should not matter how the power is hooked up to the solenoids, since they are isolated from the control terminals.
Here is how that works on the earlier system with 4 solenoids. It looks complicated, but if you trace out the wires and note what hooks to what when each pair of solenoids are turned on, it makes sense.


Now, I am assuming that the Warn switch is using the newer system. Its smaller, and you only have to turn on one solenoid at a time.
Here is how that works



The thing to realize in this case, is that the "end" terminals are NC, and the side terminals are NO. One difference between this and the four solenoid system, is that all three terminals are tied together when the solenoids are off.

One of our problems, is how are the solenoid coils wired in the switch?
Since there are three spade terminals, it would seem logical that you should ground one and put +12 to one or the other of the outside ones to select forward or reverse.
There is no reason for any of those three terminals to be hooked to the big lug terminals in any way.

FART! I think I just saw what is wrong......

Do this: Disconnect the wires from the controller to the switch.
Hook the controller to 12 volts, don't tell it to run.
Measure between each pair of motor terminals. You should have 0 volts.
Now, to make sure something is not wired funky, put one meter lead on the negative terminal of the battery, and measure each of the four motor terminals. You should have 0 volts again. If not, its not a huge problem, we will just have to wire it differently.
If all that checks out, then do this:
Leave one meter lead hooked to ground, tell the controller to go forward, and test one terminal each of the two motor terminals. It does not really matter which one you test, but be sure its the same on on both pairs.
For example, use the outside terminal on each motor hookup, the one that is parallel with the side of the housing.
One of them should have +12 to ground and the other should not.
Then tell the controller to go in reverse, and the two connectors should swap voltages.

If all that works, we should be in business.

If that all checks out, then you need to hook ground to the center terminal of the Warn switch, then hook one of the two terminals you tested to one of the outside terminals and the other outside terminal should hook up to the same terminal on the controller but the one on the OTHER motor connector.
You should have one wire on each motor connector on the controller, NOT two wires on the same connector.

Now, in my mind, as I was writing that, I very carefully kept things logical, and spelled out each step precisely. Which means it probably makes no sense at all.......

The most important thing in all this, is that you should NOT be using both terminals on one motor output on the controller. Only one terminal per output.

EDIT: I was going to upload this last but got distracted when I realized he was using both terminals on the same motor output.
Here is how someone else wired a remote control to that switch.

 

[pblaze725]

wow that’s a lot of information for me to process.

Give me a sec to eat this like an elephant.


@rampage you can buy the DeWalt power doc in the Amazon for $20.










I’m using this one for Milwaukee.



Yes that was the RX 23 the plastic is melted at the power to motor terminals.




This is the RX19 , the 4wd version of the RX23









I also have the RX30, which is a 24v circuit.


this has 2 power to motor posts, one for each motor
Instead of both motors connected to one.

Also the power to the steering motor was reversed.

This unit worked pretty good with just the 18v battery only but if I remember correct I had an issue with the steering.








This is the wiring instructions that came with the Warn switch.


when I measure the volts in the posts they both have 12v when power is on.That is with the probe on the ground and the other on a post it has 12v.
With the probe on power both posts read 0v

measuring with the probes on each post is 0v



Nom nom nom

 

[pblaze725]

It’s too late I’ve already used the Jeep wires as shown. For a short bit.


Yes I have the same motor speed controller as in the video


the wiring is simple power & ground in , power & ground out.

 

[pblaze725]

About the 40 vs 4 amp.


I snapped a pic of the multimeter while running a test and this is what it looked like.






Looking for information I saw this under the Q&A section from the RX19





it says the seller was the one to answer.

maybe a low battery or something else gave me a low amp reading.

 

[Fordum]

Wow, what a great wiring diagram. I think that may set a record for having all the necessary information presented in the worst possible manner.
Does settle one thing though. Its set up for a two terminal winch motor, so it definitely will work on your setup.

Second, I need to quit this thread. Not because of anything you or Rampage have said or done, but when I start going as far off the rails as I did in my last post........
Its strange. I remember every step of my logic, and can see exactly where I veered off into the weeds, but have no idea why.
For whatever reason I did, you can use the both terminals on one motor output, just forget what I said before.

OK if you are willing to take one more chance with my apparently addled brain, lets try this.
If I am understanding you correctly, the whole problem is that the controller is using grounding, or negative logic to power the motors.
In other words, as you know, for a motor to run it has to have positive on one terminal and negative on the other. Your controller, instead of just having the two motor terminals open when its not commanded to go anywhere, is putting +12 on each terminal.
Then, when you tell it to go, it grounds (hooks to negative) one of them and the motor runs.
Which why you are having the problem. Instead of hooking the center terminal on the Warn switch to ground, hook it to +12.
Then hook the two terminals on the controller to the outside terminals.
When the controller is in stop, all three terminals will have +12, and nothing will happen. When you command movement, one of the outside terminals will go to ground, and that will turn on the switch in that direction. In other words, just move the center wire on the switch from the negative terminal of the battery to the positive and it should work!
I realize I am overexplaining this, but I am using the explanations to try to back stop my logic and make sure I stay on track.

 

[pblaze725]

Thanks Fordum,

out of frustration I tore it all apart and installed the RX30 (24 bolt unit) and the 18v battery only.

Did I mention I got some supped up 40k RPM motors?

This setup hauls a$$! Way too fast for my kids.

if I install the motor speed controller before the control unit to slow it down the control unit gets hot. oh well.

It’s easy enough to unplug it and go back to winch relay. That’s the fun part I can just interchange all these parts in different configurations.

Maybe after work I can switch it all back.

 

[Fordum]

You don't need a slower car, you just need faster kids.....
How do you expect them to learn if you don't let them get a few bruises? What is going to happen when they get behind the wheel of a real car if they haven't learned too much speed has consequences?

But, seriously, that speed controller you posted the pic of says its good to 80 volts, and 30 amps. It probably would not handle reverse polarity, but in theory you should be able to put it between the controller and the motors to change the voltage to them without affecting the voltage to the controller.

It would only work in one direction, but if it does, we could rig up a second one wired in reverse with relays to switch between the two when you wanted to back up.
In that case, you could even set reverse to be slower than forward. But, having reverse be faster than forward would be awesome.
Really teach them some driving skills.......

At least I think all that would work. I'm just hoping I can dress myself properly this morning..........

 

[Fordum]

Well, don't forget everything I just wrote, I don't think I went off the rails that time, but it looks like everything I did write may be obsolete.

Check this out.
https://www.amazon.com/Sydien-10V-5...GFM53H7/ref=psdc_306577011_t1_B071NQ5G71?th=1

Not only is it a little heavier duty than the one you have, it has a readout, not that having a readout helps in any way. its just cooler than the one you have.
But, the important part is the little three position rocker switch.
Its a forward/reverse switch, with center brake.

Which, should mean, with a little wiring work, it will drive the car directly. The problem would come in when you tried to run it with the remote controller.
You would not have native reverse capability.
But, a couple of relays with diodes would solve that.
Hook the controller to a couple of relays through diodes so that one or the other would fire according to the polarity of the voltage coming out of the controller.
The power for the motors would come directly from the battery through the two relays and then to the speed controller.
When either relay turned on, one set of contacts on each would supply power to the speed control, and a second set of contacts would select forward or reverse.
When both relays were off, no power to the speed control.

A small electrolytic capacitor across the power input to the speed controller might help act as a "shock absorber" for the speed control in case of sudden switching.

At least all that seems to make sense now. Hope it holds up. @rampage, check behind me and make sure I'm not just wandering around behind the little animals again....

Meanwhile, I'm headed outside to crank a 90hp Mercury motor on the back of a pontoon boat for the first time this year.
More people want to go fishing this weekend than the boat should have to handle weight-wise. Which means I'm darn sure going to be the one to run it.
Plus, I'm going to insist that we go on the smaller Chipola river instead of the big Apalachicola. If that stupid thing submarines or flips, its a lot easier to swim to shore when the shore is 20 feet away instead of 200..........

 

[centexk5]

So I'm still slacking on getting mine finished up but while researching and reading up I stumbled on this:

https://kerneltoy.com/collections/r...tch-children-electric-ride-on-car-accessories

As much as I hate electrical, I'm considering buying this and being done with it.

 

[pblaze725]

I saw the same wiring harness in the Amazon for around $30.

 

[pblaze725]

Here’s a run on the 24v receiver & an18v battery, no motor speed controller, middle speed setting.

 

[ZooMad75]

Dude, that's the payoff I was hoping for. Been following all the tech talk, waiting to see some screaming kids hauling ass in a toy.

Bravo. Nice touch with the kids wearing helmets. Probably kept Mom off your tail a little too. Too cool.


Now to be Johnny come lately to the party, I didn't see any discussion of using actual RC level stuff for the same end result with the ability to have remote control.

A brushless system running a 1/8th scale sized single motor on 3s or 4s lipo power would give the same speeds. The only thing it wouldn't allow is for the kids to eventually be able to drive it themselves unless you worked out a way to allow the throttle control to be done through a modified radio using the pedal as the input for the throttle. Probably the same level of engineering going the other way I guess.

 

[pblaze725]

This is RC controlled. I was holding the controller.