Upload Your Circuit Schematics & Requests Here...

[RLT]

Just a quick update on the 120-130V BRUSHED motor controller conversion:
If you have worked with the Yi-Yun / TNC Scooter controllers, you know about that irritating, even startling, Arc- spark when you make the last connection. It is normal on the 48V and lower controllers, but it can be actually DESTRUCTIVE on 100 Volts or higher.

Four times I have vaporized a solder trace or connection or a thin copper PCB trace, even without a actual short, just due to arcing, power surge , something. Fortunately, it hasn't destroyed components, but I have had to run a couple of jumpers, or rebuild / reinforce some of the solder busses, and paint on some lacquer insulation. But even doing that doesn't stop the next 'weakest link' from blowing the next time I do a hookup.

I think I have the problem solved though:
What I did is take one of those Harbor Freight three dollar car battery cutoff switches and parallel it with a couple of 10watt / 4.7K power resistors. Make sure the switch is off when you make the final wiring connection; The resistor lets the controller partially power up 'gently', then when you cutout the resistor with the switch, there is no arcing, no vaporization of connections.

Don't know if that is the optimum ohms for it... It was just what I had handy, and it seems to work fine.

I also did some more component substitution: Replaced the seven 330 uF caps with four 680uF 200V 105 degree ones:
http://beta.mouser.com/Search/ProductDetail.aspx?R=381LQ681M200J022virtualkey59850000virtualkey5985-381-200V680

They fit inside the original controller box just fine (if you put them on longer leads so that you can lay them sideways). They even provide a little more power and make for a much neater configuration.

I also replaced the 'Frankenresistor" with a couple of 2.2K ohm 5 watt aluminum housed power resistors in series. (the reason I used the two X 2.2K is that is the closest I could come to the calculated 4.4K I needed.). That works OK, but it gets a little hotter than I'd like.

I think I'm going to replace it with a higher watt 4.7K ohm aluminum housed resistor. That will hopefully make it run a bit cooler, and maybe let me run at 144V.... SOMETHING... I don't know what, is cutting out if I go over about 135V. Not burning out; It works fine if I drop back down under 135V.

Will post some photos when I get a chance.

 

[fechter]

That seems odd.

Possibly try checking the input voltage on the 7815 while it's doing this.

Yes, a pre-charging resistor across the switch is highly recommended at any voltage. The value is not critical, but it is good practice to pick a value that will withstand the full pack voltage continuously.

 

[RLT]

Congratulations on your success Frank.

Here are some photos of the revised 130V controller:
It is a lot neater and a lot safer with the upgrades:

• Four 680uF 200V caps instead of the seven 330uF; They fit inside the original controller box instead of half of them flopping around outside, yet actually give a little more power.
  'Frankenresistor' replaced by a heavy duty aluminum housed 4.7K power resistor.
  http://www.az123.com/130v_cont/rev/RevCont2.jpg
  I actually intended to use a 15 or 25 watt resistor here, but clicked the wrong button when I ordered from Mouser. I don't think I have to worry about this 50 watt monster overheating.
  
  Controller box closes up nice:
  http://www.az123.com/130v_cont/rev/RevCont3.jpg
  Still have one Frankensteinish component though: To prevent that nasty arcing when you hook up to the batteries (especially at 120V or more), I paralleled a couple of 10W 4.7K cement power resistors across the terminals of one of those $3.00 Harbor Freight battery cutoff switches. This was just a 'quick and dirty' hookup. The resistor values were chosen just because they were handy; I don't know what the optimum value might be, but these seem to work just fine. When I actually 'hit the road' it will be put in a project box to be safer and look better.
  http://www.az123.com/130v_cont/rev/RevCont5.jpg

It works!:
http://www.az123.com/130v_cont/rev/RevCont4.jpg
(At least sitting on the floor with no load, or whatever load I can put on it by hand; This motor has some serious torque. Even if you try to stall it by hand starting with the throttle off, by the time it hits 4 amps, it is going to start cranking even if you are a 'GI Joe with the Kung-Fu Grip').

I haven't tried this revision yet at over 135V; Probably no need to anyway. 2340 watts should be enough if you gear it right .

 

[fechter]

I use a 5w precharging resistor on my scooter. Unless something is screwed up, the resistor is not normally dissipating much. It is good practice to size the resistor so that it won't burn up if the controller is shorted (or on with the throttle activated).

It might be cool to use a small 120v light bulb instead of a resistor (honey... what happened to the Christmas lights?). If the controller was shorted or stuck on, the light would be bright. Under normal conditions, it would light up for a few seconds then dim down.

 

[Doctorbass]

Hi all!!!

I'm new to this forum but have been reading it for the last couple of months regularly.

I've just finished an extender board for the YK42-x series of controllers with the help of Fechter & RTL. The idea is that you populate the brd according to your requirements and take a 36V/40A controller and turn it into a 60V or 72V controller at either 25A, 40A or 100A based on the number of parts you add.

Schematics and PCB layout as well as assembly details are posted below...

http://www.theworkshop.ca/energy/dirt_e/2/2.htm

I can appreciate that this may seem redundant given that RTL has taken the YK42-x upto 120V with just the original brd, but I found that it would be impossible for me to solder in such tight quarters.

Hello Frank!

I just visited your website.

That's impressive what you did with all this used stuff!... that's great to have documented all your project and carefully explaned all your work.
It's very rare that people that diy will take time to describe all what they do like you do!

Welcome here! :wink:

Doc

 

[rkosiorek]

i have been wondering about those add-on diodes. why are they added? is not the built in body diode of the fet enough?

if they work so well here should we also add similar diodes to BLDC controllers? one in parallel with each fet?

will any old schottky rectifier do? or are we looking for very fast response units.

rick

 

[fechter]

On a brushed controller, you need diodes that go across the motor. The FET body diodes are not in the right location to catch the kickback.

On a brushless controller, there are FETs on both the high side and the low side, so the body diodes will do the job.

 

[ngocthach1130]

I just bought a Yi-Yun 36v controller Model YK40-3 and hoping to reproduce the same result as RLT did with the Yi-Yun Model YK42-4. The next voltage step i want to take is take is 60v. But i would modify the controller like RLT version which leave room for up to 120V+. I didn't want to use the other controller because they only have battery, motor, throttle connection. On the schwinn scooter there is other function such as brake cut off switch. Didn't want to let feature like that go to waste so i bought the YK40-3. Do i proceed the same way as the other controller considering mine is more complex? I don't care about charging port. I'll remove the battery when charge.

The board use 4 - 330uF 63V capacitor. Upgrade this to 4 - 640uF 200v
3 Schottky Diode STPS20S100CT
http://www.alldatasheet.com/datasheet-pdf/pdf/111350/STMICROELECTRONICS/STPS20S100CT.html
Going to replace them with these - MBR20200CTG

3 IRF1010E 60V 12mohm 84A Mosfet - Going to replace them with FDP2532. 220 package with teh metal screw tab.

Am I heading in the right direction or is this controller hopeless and i'd have to buy the YK42-4?

 

[rkosiorek]

<snip>

What are the orginal shunts made of?

What resistance are they?

What is a good replacement, that can predictably jump from say 40Amp to 50, 75, 100 or 125Amps... I suspect that ohms law holds the answer, but measuring such small resistances is a problem with standard DMM's.

these resistors are made from some sort of resistance wire. either a plated Nickle Chromium (NiChrome) or Manganin alloy.

it really is not difficult to measure these low resistances. what you need is a 1ohm or 1.2 ohm precision power resistor about 5 or 10W in size and a fully charged NiCad C or D cell that can deliver an amp or so. hook the 1ohm reference resistor in series with the shunt and the battery. measure the voltage across the 1ohm resistor and the shunt. the resistance of the shunt will be the same ratio as the voltages.

for example if the measured voltage is 1.1V across the 1ohm resistor and 0.006V across the shunt. The current through the 1ohm reference resistor would be calculated as Iref=Eref/Rref = 1.1/1.0 = 1.1A.
the current through the shunt will be the same 1.1A using ohm's law again Rshunt =Eshunt/Ishunt = 0.006V / 1.1A = 0.005ohm.

the same technique could also be used to measure motor windings.

of course for the more sophisticated (read as nearsighted and stupid) you could waste the time and money to build a precision 1A current regulator and then measure the resistance directly as i did. Bob Mcree pointed out the simpler method.

 

[rkosiorek]

On a brushed controller, you need diodes that go across the motor. The FET body diodes are not in the right location to catch the kickback.

On a brushless controller, there are FETs on both the high side and the low side, so the body diodes will do the job.

Did ya ever have one of those Homer Simpson moments where the answer is so simple and obvious that once you read it you just have to smack yourself in the forehead and say DOH!!!!

this was one of those.....

this may also be a problem area on the Crystalyte 48V 35A brushed controller. it only has a single 20A diode to catch the kickback. i have a couple of these with all of the FETS and diode blown even though the fets should be able to handle a lot more than the current that blew them. the output stage there is 3X IRF2807 fet + 1X STPS20S100CT diode. i think that the next time i blow one i'll add a second or third diode off board. there is enough room on the heatsink for it.

the question is: do you really need to maintain the ratio of one diode per fet? or is that just a safety factor?

 

[fechter]

I think the current rating of the diodes ought to match the current rating of the FETs.

 

[ngocthach1130]

Yeah the board use a LM7815 voltage regulator. I looked up the datasheet and it is for 15v. The regulator is located to the left of the 4 capacitors.

So it look like it is basically the same modification. Anything else I should be replacing? Anyone familiar with the Yi-Yun 40-x? I'm going to go ahead and order the parts. Will start modifying it when it come. The 640uF caps is a little big though. The dimension from Mouser say 25mm diameter. The stock one is only 10mm so one capacitor will over take the whole slot for one capacitor. I hope the case fit with cap laying on the side. This controller is smaller in size than the yi-yun 42-x.

*Sigh* Christmas is already doing massive damages to my wallet. $42 is parts alone from Mouser.

 

[fechter]

I think you got it. I couldn't tell for sure from the pic if you had the right resistor circled, but Franks description is good.

Most of the shunts I've run across seem to be around 1 milliohm. To boost the current, you can fill the space between two wires with solder. This about doubles the current. Plan B is to take about 4 inches of 12ga. wire and solder a loop across the shunt. You can vary the length of the wire to adjust the current. You can also put a switch in the wire to switch to stock current level. Using a switch might cause some variation in current each time the switch is used, but I think it should be OK.

 

[rkosiorek]

Further to the shunts...

On the YK42-x with one shunt in place at full throttle I measure 3 Amps of current flow between the top of the bat pack (at 75V) and the controller... And 0.019V Vdrop across the single shunt. The current measurement is with a cheap Asian meter, though the VDrop is measured with a Fluke meter (so I hope it's more accurate).

Is it reasonable to extrapolate the Resistance of the shunt as below???

0.019VDrop/3.0A =0.006ohm or does the load of the actual controller ie;switching losses etc skew the value?

<snip>

on the shunts used in the Crystalyte controlers each individual one measures between 0.004 ohm and 0.006 ohm. that averages to 0.005 ohm plus or minus 1percent. 1 percent is the tolerance of my 1 amp current source. i think that your measurement is well in line with that.

not having one of your YK42-x controllers i can't say that it would be identical but it is inline with what i have measured on the crystalyte controllers. the shunt on the crystalytes is 0.055 inches in diameter and with bends and all it is about 0.5 inches long. i have measured 12 individual ones from the brushless 20A and 40A controllers which appear to be identical in dimension to each other. the circuitry in these controllers is identical except for the output sections. the 40A one has twice as many fets and shunt wires as the 20A one. so my theory is this each of the shunts used in the crystalyte controllers is 0.005 ohm good for 10A on the current limit. the 20A version uses 2 in parallel and the 40A uses 4 in parallel. so for a 50A you need 5 in parallel and 60A needs 6. etc.

somewhere in my storage unit i have a bag full of similar wire shunts i got in an auction lot when a local company that made power supplies for Nortel folded. i never thought that i would need them until now. one more reason to get out there and do some cleaning in the storage unit.

rick

 

[rkosiorek]

Rick,

I know Nortel is a huge company, but thier headquarters are located up the valley from us in Ottawa, Are you in Eastern Ontario???

one of their manufacturing plants and a spin-off PC board manufacturer used too be in Belleville, Ontario. now all that we have left is some type of research division. they used to be the second largest local employer (next to the Sears Catalog warehouse)

so if you are in the Ottawa region i'm just a little west of you.

rick

 

[ngocthach1130]

Updates on the modification of the Yi-Yun 40-x 36v controller. I desoldered the caps, diode, and mosfet and applied the upgraded one. I left the original resistor just as RLT to test at stock 36v. Put 36v through it and turned it on... Nothing. So the genius that i am decided to crank it up to 84v. Turned it on...Pop, hiss, smokes. There goes one of the capacitor. Filled the room with noxious gas and the speed controller is now filled with some nasty smelling liquid. I have since removed the bloated cap and i think the reason might be i connected the cap wrong. I'm pretty sure cap doesn't have polarity but on the board, the spot where they connected the cap have one line drawn through one connection. I had thought this might link with the black line running down on one side of the capacitor. The one that blew was the one i connected the capacitor wrong, with the connector on the black band side not going into the hole with the line drawn through. Someone enlighten me on where i went wrong.

Also the stock throttle on the Schwinn S1000 use 6 pin connector with 3 wires for the status LED. I don't have the pin out for the connector so i assumed the 3 outer wires, red, yellow, green, to be 5v, ground, and signal wire respectively. Will order another 640uF cap and retry. Lets hope next time won't be as explosive, nor dangerous.

 

[fechter]

I hate it when that happens :x

Those kind of capacitors definitely have a polarity.

Now you know how to blow them up intentionally if you want to.

 

[rkosiorek]

aw it was just a little one. and it was enclosed in the case as well. wait until you get a 340,000 mfd one to blow in open air. it sounds like a hand grenade.

the oily stuff (dielectric oil) is non-conductive and depending on the formulation it can be quite toxic. but the worst problem with it is that it can make it hard to solder to anything that it has coated.

i usually like to clean the whole board after desoldering the bad cap first with tri-chloro-ethylene(TRi-CHLOR, TCE or Trike) followed by warm soapy water. rinse with warm watter and hang it to drip dry overnight. using compressed air to help drive the moisture out is also a good idea.

rick

 

[Beagle123]

I'm using a power supply to charge my batteries, and I don't want it to run all night. So, I made an electronic cutoff switch to unplug the power supply when it senses that the current drops below 10 amps. Its my first circuit, and I'm proud to say it works. However, I am experiencing a problem: As the current drops, it gradually turns off the power to the power supply. This makes the power supply sputter on and off before shutting down. The comparator and the transistors aren't perfect on/off switches.

I've searched for more perfect swiching components including flip-flops, scrs etc, but everything turns off slowly. I need to create an electronic pulse, or have it snowball off. I was thinking a capacitor could drain for a second, holding the power off until the power supply is off.

Any suggestions?

 

[fechter]

OK, one way to fix that is to add some hysteresis to the circuit. Add a resistor between the output of the op-amp and the + input. This way when the amp starts to turn off, it will pull down the signal from the sensor and make the amp think the current just got even lower, forcing it full off until it gets really low.

For this to work, you also need a resistor between the output of the sensor and the + input so that the input can be pulled down without overloading the sensor output. If this series resistor is like 10k and the feedback resistor from the output is like 100k, it will drop the input by about 10%, which should be enough to keep it from chattering.

I can't really read the schematic posted at its present resolution, so I'm guessing a bit as to what values you put in there. You might need to send me a higher res. version so I can read it.

 

[Beagle123]

I"m actually using a comparator, not an opamp. I'm trying to understand what you said now. Here's a higher resolution image:

 

[fechter]

It's much better when I can read the diagram

Anyway, the approach would still be the same, put a resistor across pin 1 to pin 3. The smaller the resistor value, the more swing there will be in the set point. If I read things right, this is all you need to do. Make it about 10 times greater value than your current adjusting pot.

The pot sets the trip point. When the current matches the trip point, the added resistor will tweak the trip point to a higher value. This shoud prevent the circuit from oscillating.

Adding the resistor will change the pot setting a bit, but it's adjustable.

Instead of a resistor, you could also use a diode to pull the + input up.

Something doesn't look right about the pnp transistor driving the relay. I think it's drawn in upside down or something. You should also probably add a resistor between the base and pin 1 on the comparator to limit the current. 1K?

 

[Beagle123]

Thanks fetcher,

I learned from experimenting that MOSFETS have a much faster transistion than any transistor. I test the action by turning a pot until it trips the circuit. I watch a led to see when it turns off. I can easily make the led dim slowly with any transistor, but when I found a MOSFET that worked with 4v, it triggered quickly. I could barely get it to give a voltage that's not 4v or 0.05v. So I'm going to substitute the MOSFET for the resistor.

Last night I fried the current sensor. It sucks! The damn thing is all soldered in (five places including 10 guage power lines) and glued to the board. I guess I'm going to start again from scratch. I guess my first one was a learnig experience. (the soldering wasn't too pretty either.) I accidentally touched a probe across the output pins. Uhhh!

 

[fechter]

Last night I fried the current sensor. It sucks! The damn thing is all soldered in (five places including 10 guage power lines) and glued to the board.

Oh, that does suck. Hall sensors are not very tolerant of shorted outputs.

I have an extensive collection of parts I've fried. It's part of the learning experince.

 

[RLT]

Picked up a couple of the 24V Yi Yun 42 series brushed motor controllers.

Pretty much the same as the 36V and 48V ones.
The only difference is that there is just a 1N4007 diode instead of the 7815 voltage regulator and power resistor, and the big caps are (6X) 470uF 50V instead of (7X) 330uF 63V in the 36V and the (4X) 470uF 100V ones in the 48V ones. And there are some solder shorts across all three shunts.
The MOSFETS and Schottkys are the same: 3435 & 20100.

I haven't hooked it up with anything yet; I'd guess it would work fine on up to 32V or so unmodified? , maybe 36V? Above that, probably have to put in a 7815 and the proper value of resistor. But since the 36V controller is only three dollars more, it is probably the best deal if you are going to modify for higher voltage... Better than the 48V one that is 20 dollars more.