Author Topic: Greenworks 60v battery Ohm terminal  (Read 24775 times)

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Offline typoknigTopic starter

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Greenworks 60v battery Ohm terminal
« on: February 11, 2021, 01:58:48 am »
I got a Greenworks 60v snowblower that didn't have a battery. I'm on the DeWalt stack so I have several 60v DeWalt batteries. I 3D printed an adapter and went to test it out, but the snow blower will only run for 3 seconds then stops. Took it apart to see what was going on and found the electronics are potted :(

A Greenworks battery has 4 terminals and the snow blower uses 3 of them. The outter two are power and ground, the other one has an ohm symbol on it.  What precious little info I've found about that terminal indicates it is for "battery communication". The wire from the snow blower that would attach to the terminal in question produces 5v when I engage the snow blower and remains 5v for at least 3 seconds or until I disengage the snow blower.

I've tried putting various resistors across it to ground, but that hasn't worked.

Any thoughts? What does this wire do? How do I make it happy?
« Last Edit: February 11, 2021, 02:19:59 am by typoknig »
 

Offline aargee

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Re: Greenworks 60v battery Ohm terminal
« Reply #1 on: February 11, 2021, 02:29:35 am »
I'm guessing that it is a thermistor. Mostly used by the charger but will also get warm if there is an excessive discharge through the pack.
How it is connected, I'm not sure. Mostly between that terminal and ground in packs I have.
Maybe about 10k would be worth a go or get a resistance wheel and experiment.

I don't *think* it would be as complex as some one-wire device for either temperature or ID of some sort.

I'd be interested to see your battery adapter though, I've been tempted to try something similar here for a DeWalt battery to a Black and Decker tool.
Not easy, not hard, just need to be incentivised.
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #2 on: February 11, 2021, 02:59:16 am »
From my reading I also thought it might be a thermistor. I tried a 10k and 11k with no luck. I'll try some more in that range and see what happens.

I made the adapter in several parts. The one I'm using now was a "failure" in the sense that I neglected to account for some nooks and crannies of the Greenworks battery hole and had to take the Dremel to the adapter to make it fit. Printing a new one as we speak. Once I've verified my design I'll share it.
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #3 on: February 11, 2021, 04:00:20 am »
Tried 10k to 11k in increments of 100 ohms with no luck.
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #4 on: February 11, 2021, 11:27:08 pm »
Looks like the wire is expecting a PWM signal from the battery.

https://endless-sphere.com/forums/viewtopic.php?f=1&t=79384&start=100#p1559001

This Arduino code will apparently generate the correct pulse for a brushless 60V Greenworks tool. Based on the thread I linked to it seems 80V batteries have a different signal.

Code: [Select]
// written 5/26/2020
// Working battery interface signal from the "Omega" port
// of a Greenworks Pro 60V battery

#define PIN 6

void setup()
{
pinMode(PIN, OUTPUT);
}

void loop()
{

digitalWrite(PIN, HIGH);
//Delay 188,000us
for(uint8_t i = 0; i < 188; i++)
{
delayMicroseconds(1000);
}

digitalWrite(PIN, LOW);
delayMicroseconds(400);

for(uint8_t i = 0; i < 3; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(200);
}

for(uint8_t i = 0; i < 9; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}

delayMicroseconds(100);

for(uint8_t i = 0; i < 1; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(200);
}

// 5
for(uint8_t i = 0; i < 4; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}
delayMicroseconds(100);

for(uint8_t i = 0; i < 4; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(200);
}

for(uint8_t i = 0; i < 3; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}

digitalWrite(PIN, HIGH);
delayMicroseconds(1000);
digitalWrite(PIN, LOW);
delayMicroseconds(200);

for(uint8_t i = 0; i < 2; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}
delayMicroseconds(100);

for(uint8_t i = 0; i < 1; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(200);
}

for(uint8_t i = 0; i < 2; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}

delayMicroseconds(100);

for(uint8_t i = 0; i < 4; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}

delayMicroseconds(100);

for(uint8_t i = 0; i < 3; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}

delayMicroseconds(100);

for(uint8_t i = 0; i < 2; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}

delayMicroseconds(200);

for(uint8_t i = 0; i < 1; i++)
{
digitalWrite(PIN, HIGH);
delayMicroseconds(100);
digitalWrite(PIN, LOW);
delayMicroseconds(100);
}

delayMicroseconds(100);


}

I don't have an Arduino so now I have to decide if I want to buy one or try port the above code to an ESP8266 (and buy a voltage regulation to get from 60V to 3.3V) or de-pot the electronics and try to circumvent the required signal.
« Last Edit: February 12, 2021, 12:12:58 am by typoknig »
 

Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #5 on: February 12, 2021, 01:19:55 am »
I bought a used Greenworks 60V Self Propelled mower (w/o batt) that I am working on converting also.

I have the same problem-Runs for 3 seconds then shuts off and beeps 3 times.

I found the posts about the Arduino and bought a Nano. Programmed one of them and the signal looks good on the scope.

I connected pin 6 to the Omega terminal on the mower and excitedly turned it on.

The result-it ran for about 3 seconds then shut off and beeped 3 times?

Not sure what to try next...I think the problem is still with the signal... Weird that typoknig said it puts out 5V but the other forum posts suggest it takes in a signal?


1172186-0
1172190-1
1172194-2





« Last Edit: February 12, 2021, 02:09:23 am by BradK »
 

Offline james_s

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Re: Greenworks 60v battery Ohm terminal
« Reply #6 on: February 12, 2021, 05:02:24 am »
I really wish some of these companies would get together and develop a common battery standard that works across several brands. I have at least 5 different cordless tool battery standards and none of them work with each other. Wishful thinking I know.
 
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Offline bob91343

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Re: Greenworks 60v battery Ohm terminal
« Reply #7 on: February 12, 2021, 05:08:23 am »
I solved that problem years ago.  I no longer use battery operated tools.  So if I have to run a power cord, no big deal.  Not only is it more efficient but will not die in the midst of use.  The cost is much less.  The tool longevity is better.
 
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Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #8 on: February 12, 2021, 05:44:07 am »
I bought a used Greenworks 60V Self Propelled mower (w/o batt) that I am working on converting also.

I have the same problem-Runs for 3 seconds then shuts off and beeps 3 times.

I found the posts about the Arduino and bought a Nano. Programmed one of them and the signal looks good on the scope.

I connected pin 6 to the Omega terminal on the mower and excitedly turned it on.

The result-it ran for about 3 seconds then shut off and beeped 3 times?

Not sure what to try next...I think the problem is still with the signal... Weird that typoknig said it puts out 5V but the other forum posts suggest it takes in a signal?


(Attachment Link)
(Attachment Link)
(Attachment Link)

I think the tool (in my case the snow blower) is just pulling the pin high to 5v.  Once connected to the battery it could be pulled low and then have pulses generated on it as well.

As far as what to try next, that thread I linked to indicated that the 60v motors with and without brushes require different PWM signals. Maybe try a different one? Or if you have a Greenworks battery and the mower works with it, try hooking up the scope with it running and seeing what your signal is then program the Arduino as needed.
« Last Edit: February 12, 2021, 05:56:28 am by typoknig »
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #9 on: February 12, 2021, 05:52:09 am »
I really wish some of these companies would get together and develop a common battery standard that works across several brands. I have at least 5 different cordless tool battery standards and none of them work with each other. Wishful thinking I know.

I hear ya.  In my research I found that that electrically Greenworks, Kobalt, Snapper, some Ryobi, and some Walmart brand (Proworks, Protools, or something generic like that) are all the same within their respective voltage ranges. The cases are different though. DeWalt is different animal it seems. DeWalt 60V tools have 6 pins tool side and 8 pins battery side. I hooked up the scope to it and did a few tests to see if any of its pins generated a PWM signal when the battery was under load. I found no such signal, but my tests weren't exhaustive.
« Last Edit: February 12, 2021, 06:33:14 am by typoknig »
 

Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #10 on: February 12, 2021, 06:44:18 am »
james_s

I agree. If I can't get a tool to run on my Ryobi batteries (which is all I have) I will get something else.
I converted a snow blower (Snowjoe ION18SB) a few months back to run on dual Ryobi batts and it works great.
That tool convinced me that I want a cordless lawn mower as well, just have to figure out how to make it work which is what brought me here.

typoknig

There are 3 different programs for the Arduino that I saw on the other forum. I have two of them. This first one they said did not work.
I will try the other tomorrow or this weekend and see what happens. Also, I am considering buying a brand new Greenworks 60V Mower with batt to see if I can catch the signal. I really want this to work, but if I can't get it I'll just try it with a different brand mower.
 

Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #11 on: February 12, 2021, 06:58:51 am »
typoknig,

The picture in the above post is the snowblower I converted to run on dual Ryobi batts.
It's a 40V Snowjoe ION18SB. Got it on the local ads for $40, then sold the two batts and charger it came with for $150.
All I did was 3d print two cases, covers and some end clamps, then installed the cases/clamps on an aluminum bar I wrapped with black vinyl wrap.
The Ryobi 18V 4Ah batts have the same number of cells as the original Snowjoe batts and it works really well. I actually bought a second one on the local ads for $10 and converted it to run on a single 6Ah Ryobi batt for my mother in laws small driveway. Used a DC boost converter to get the voltage up. I have yet to test it though.

UPDATE: Forgot to mention the Snowjoe does not require a 3rd terminal on the battery, it will work with any batteries that provide 40V.
I removed the back cover, put ring terminals on the wires from the Ryobi batts and put them right on the existing terminals that I found under the back cover.
I have never had a gas snowblower so I may be biased but I am more than impressed with it. So much better than shoveling and now I actually want it to snow LOL.


« Last Edit: February 12, 2021, 07:10:20 am by BradK »
 

Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #12 on: February 12, 2021, 06:38:47 pm »
Tried a few different things today.

First I uploaded the other program to the Arduino, checked it on the scope and connected everything.
I tried it with the same results (powers on for 3 seconds then shuts off and beeps 3 times).

I then removed the Arduino connection to the Omega port on the mower side the took a voltage measurement.
I'm getting 2.8V between the Omega port and ground on the mower side?

I also considered that my Ryobi batteries BMS's might be cutting power from an overcurrent, but I ruled that out in a few different ways:
1. Manufacturer specs claims 60V 5Ah battery will run 60 mins so avg current draw will be 5 Amps.
2. My batteries are rated for 30A peak
3. If I don't turn anything on but just press the lever switch on the handle I still get the 3 beeps after about 3 seconds

Seems the Omega port is still the problem here (or my motor controller). For now I am at a loss, without an actual battery I can't see what I need to so I might just buy one in the future and go from there.
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #13 on: February 12, 2021, 09:04:45 pm »
I went ahead and ordered an Arduino instead of porting the code to an ESP8266 and having to worry about a 3.3v to 5v level shift. Once I get it and try it out I'll post back.
 
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Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #14 on: February 14, 2021, 08:39:18 pm »
Received the Arduino Nano in the mail to day and got it programmed and hooked up. I've tried the 3 Arduino "sketches" that were available on the website I linked to in my previous post to no avail.  I'll do some more hunting for other Arduino code, but I might have to breakdown and buy a battery unless someone has a battery and can scope out the signal.
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #15 on: February 15, 2021, 01:16:13 am »
I reworked the code I found at https://endless-sphere.com/forums/viewtopic.php?f=1&t=79384&start=75#p1275544 to make it easier to pick between various pulse mappings.  I used a scope to verify the code is doing what I expect it to do, but neither of the pulse mappings are working for my 60V snow blower.  Maybe it will help someone though.  Just modify "SELECTED_BATTERY_TYPE".  I'll either find or buy a battery this week to get to the bottom of this mystery.

Code: [Select]
// Battery types
#define BATTERY_TYPE_60V 1
#define BATTERY_TYPE_80V 2

// Change SELECTED_BATTERY_TYPE to one of the battery types listed above
#define SELECTED_BATTERY_TYPE BATTERY_TYPE_80V

// Pin number to put signal on
#define PIN 6

#if SELECTED_BATTERY_TYPE == BATTERY_TYPE_60V

#define NUMBER_OF_PULSES 41

// All hold times are in microseconds
uint16_t pulse_low_hold_times[NUMBER_OF_PULSES] = {
  400,
  200, 200, 200,
  100, 100, 100, 100, 100, 100, 100, 100,
  200, 200,
  100, 100, 100,
  200, 200, 200, 200, 200,
  100, 100, 100,
  200,
  100,
  200, 200,
  100,
  200,
  100, 100, 100,
  200,
  100, 100,
  200,
  100,
  300,
  200
};

// All hold times are in microseconds
uint32_t pulse_high_hold_times[NUMBER_OF_PULSES] = {
  100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100,
  1000,
  100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100,
  189000
};

#elif SELECTED_BATTERY_TYPE == BATTERY_TYPE_80V

#define NUMBER_OF_PULSES 41

// All hold times are in microseconds
uint16_t pulse_low_hold_times[NUMBER_OF_PULSES] = {
    400,
    200, 200, 200,
    100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100,
    200, 200, 200,
    100, 100, 100, 100, 100,
    200,
    100,
    200, 200,
    100,
    200,
    100, 100, 100,
    200,
    100, 100,
    200,
    100,
    200
};

// All hold times are in microseconds
uint32_t pulse_high_hold_times[NUMBER_OF_PULSES] = {
    100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100,
    500,
    100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100,
    189900
};

#endif

void setup() {
  // set pin 6 to an output
  pinMode(PIN, OUTPUT);
}

void loop() {
  // Loop through all the pulse data
  for (uint8_t i = 0; i < NUMBER_OF_PULSES; i++) {
    // Pull pin low
    digitalWrite(PIN, LOW);

    // Hold pin low for required amount of time
    delayMicroseconds(pulse_low_hold_times[i]);

    // Pull pin high
    digitalWrite(PIN, HIGH);

    // If we aren't on the last pulse, assume hold time is small enough to be handled by the delayMicroseconds function
    if(i + 1 != NUMBER_OF_PULSES) {
      // Hold pin high for required amount of time
      delayMicroseconds(pulse_high_hold_times[i]);

    // If we are on the last pulse, assume hold time is too large to be handled by the delayMicroseconds function
    } else {
      // Split hold time into milliseconds and microseconds
      uint32_t milliseconds;
      uint8_t microseconds;
      milliseconds = pulse_high_hold_times[i] / 1000;
      microseconds = pulse_high_hold_times[i] % 1000;

      // Hold pin high for required amount of time
      delay(milliseconds);
      delayMicroseconds(microseconds);
    }
  }
}
« Last Edit: November 09, 2021, 10:16:22 pm by typoknig »
 
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Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #16 on: February 15, 2021, 10:38:44 pm »
Typoknig,

Are you getting the same result as before (snowblower runs for 3 seconds then shuts off?

Seems no matter what I do it does the same thing.

I wonder if something weird is going on...Like the controller requires an initial full voltage (GW batts are actually 64V fully charged from what I have read) before it will allow operating on a freshly inserted battery?
« Last Edit: February 15, 2021, 10:56:27 pm by BradK »
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #17 on: February 16, 2021, 04:39:07 am »
Yeah, I get the same results I've always got. I ordered a GW battery today and I should have it by Wednesday of next week. Then we will know for sure.
 
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Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #18 on: February 20, 2021, 05:00:43 am »
Typoknig,

I just ordered the Logic Analyzer recommended on the Endless-Sphere GW thread. Still looking for a good deal on a battery.
I have been watching videos on Arduino programming and looking over the code to see if I can find any errors. I'll post any thoughts/findings here.
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #19 on: February 22, 2021, 09:11:43 pm »
GW battery was delivered today.  Fully charged it is 60.53V and the DeWalt battery is 58.42V.  I wouldn't think that voltage difference would prevent it from running, but maybe?  The pulses generated were slightly different, but when I plugged them in I get the same result I had been getting.  I did notice in the waveform that the low pulses aren't pulled all the way to ground.  The low pulses that occur before the single 1000us high pulse are pulled down to 600mv and the low pulses that occur after the are pulled down to 200mv.  I wouldn't think that would be causing this issue either, but again, maybe?  I've attached a .wfm file generated from my Rigol MSO5074.
« Last Edit: February 22, 2021, 09:20:55 pm by typoknig »
 

Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #20 on: February 22, 2021, 11:43:29 pm »
Typoknig,

You mean with the GW battery your snowblower is still only running for 3 secs then shutting off?

Your 58V batt should work just fine. The GW battery I was looking at had a tag on it that said it was actually a 54V battery with a max of 60V. I also found out the 2Ah 60V batts have 15 cells in them.

Have you tried measuring both the GW battery signal and the Arduino signal at the same time then overlapping them to see if there are any differences other than the voltage offset?

I should be getting my logic analyzer this week but still looking for a good deal on a GW battery.

 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #21 on: February 23, 2021, 12:00:29 am »
You mean with the GW battery your snowblower is still only running for 3 secs then shutting off?

No, the snow blower works fine with the GW battery.  When I scope out the signal the GW battery generates and update the Arduino code to use those pulses, it still only runs for 3 sec with the DeWalt battery.

Have you tried measuring both the GW battery signal and the Arduino signal at the same time then overlapping them to see if there are any differences other than the voltage offset?

No, but I'm getting ready to set that up now.
 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #22 on: February 23, 2021, 04:27:04 am »
Didn't make any breakthroughs tonight.  The waveforms I was using where all really close to what the battery generates.  The pulses might actually be 92.6us, but we have 100us coded up.  I tried more exact pulse widths and it didn't change anything.  I am running my buck converter at 5v exactly and the snow blower pulls the Omega terminal high to 4.7V.  There are a bunch of little differences that I wouldn't think would matter, but apparently one or more of them do.  To summarize, the difference are:

1.) DeWalt battery is 58.X volts, GW battery is 60.X volts.
2.) Arduino pulls Omega terminal high to 5V (I can adjust my buck converter to make it match), snow blower only pulls it high to 4.7V.
3.) Highs and lows of pulses aren't exactly on 100us intervals.  Sometimes they are weird numbers like 92.6us for a low pulse, or 103us for a high pulse.
4.) All the pulses the GW battery pulls low before the 1000us high pulse are only pulled down to 600mv, not 0v.  After the 1000us high pulse the GW battery only pulls the low pulses down to 200mv.

I'll investigate these differences one at a time in an attempt to narrow down what is causing this battery to be such a pain.
 

Offline BradK

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Re: Greenworks 60v battery Ohm terminal
« Reply #23 on: February 23, 2021, 06:57:10 am »
Crap!

I was hoping this would be as easy as the users on Endless-sphere made it sound.
I sent one of the guys there (StinkyGoalieGuy) a PM and he replied with the following:

Quote
"This is the logic analyzer I used: https://www.amazon.com/gp/product/B077L ... UTF8&psc=1

Yeah, it wouldn't hurt to check that the Arduino output matches the code with a logic analyzer.

I'm using a battery I built from 18 a123 cells in series. They are 3.3v nominal, so ~59.4volts.

I used the logic analyzer on a Greenworks 60V battery to get the pulse pattern. Unfortunately, I don't have that battery anymore, otherwise I would check its voltage for you."

Great observations, Those all seem like very minute details but then again if its not working it must be something like that.

The other thing I have been wondering is if the pulses change with battery voltage....Perhaps the pulse pattern has to match the battery voltage ,at least initially to fool the controller?


 

Offline typoknigTopic starter

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Re: Greenworks 60v battery Ohm terminal
« Reply #24 on: February 25, 2021, 04:04:38 am »
I've took some more samples and noticed that as the snow blower starts up, the signal is different for about 2 seconds.  There are several places where the "normal" signal (the one we have been replicating with an Arduino thus far) are mixed into the starting signal, but the starting signal is predominantly large pulses (in the ms range, not the us range).  This may be a coincidence, but there are exactly 41 of the larger pulses, the same number of us range pulses in the "normal" signal.  I was going to use my scope's built in function generator to try to feed the signal back into the snow blower while actually using the DeWalt battery, but my function generator's range is 2.5v to -2.5v, so that will not work.  I'll take a couple of more samples tomorrow and see if the staring signal is the same each time.  If it is I'll try to duplicate it with the Arduino.  I've attached a waveform that shows this if anyone else cares to analyze it.

I took more samples and never saw the "larger pulses" I mentioned above again, so I guess that was fluke generated by the GW battery?  The starting signal is slightly different though.  From here on I'll refer to a "pulse group" as a series of pulses separated by a large (relatively speaking) delay.  The first pulse group always happens 1.1 seconds after the Omega pin is pulled high and only has 40 pulses, not 41.  The first 5 pulse groups occur with only a 90ms delay between them, where all the pulse groups after than have a roughly 190ms delay between them.  I duplicated this, but the snow blower still only runs for 3 seconds.  Next, the first 5 pulse groups are have slightly different delays between the pulses.  I'm getting ready to duplicate that now.

I also spliced in the Arduino while using the GW battery so the Arduino was generating the signal for the Omega pin instead of the battery.  This tells me that the minor voltage difference between the DeWalt battery and the GW battery is no the cause of the problem.

I deleted the original wave I attached and I've attached a new wave recorded from my Rigol MSO5074 which show the start sequence and several seconds of the tool running correctly.
« Last Edit: March 01, 2021, 05:10:04 pm by typoknig »
 


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