New 80 volt push mowers

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amberwolf   100 GW

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Re: New 80 volt push mowers

Post by amberwolf » Jan 09 2022 12:27am

5net wrote:
Jan 08 2022 11:43pm
In some other Kobalt models, they use "a 3ph Permanent Magnet motor with hall effect rotor position sensors."
This one definitely doesn't those position sensors. Only 3 wires, I will assume they are 3phase brushless dc sensorless.
but I am really trying to figure it out what type of motor is this, so I disassembled the housing to look for a label and took couple of photos.
It is impossible to find any information on it. Do you think you can identify what type of this motor base on this photo?

motor 1.jpg
motor 2.jpg
None of the numbers on the motor label come up in any searches; it's probably custom made for Kobalt.

Unfortunately the rotor is completely covered by the motor top bracket, so we can't see if it has magnets or just laminations. If you can get a picture at enough of an angle with enough light down in the gap between stator teeth (where the copper windings are) to show the central cylinder of the motor, so we can see the sides of it, we can see if it has magnets. I don't recommend taking the motor itself apart; some of them don't go back together correctly without factory tools. ;)

Or, if you have a thin steel screwdriver (that will stick to magnets) that will fit in that gap between teeth, without pushing against anything, you can see if it sticks to the central cylinder (rotor). If it does, it has magnets and is almost certainly a regular BLDC motor, and an ebike controller will probably run it.

If there are no magnets, a cheap ebike controller probably wont' run it.

If other models use one, it's likely this does too, but can't tell from the pics.
Only 1 battery at the time. The battery is a Kobalt 80V 5.0Ah 360W (at 72v * 5 = 360W?)
The marking on the battery is actually 80v MAX (dc symbol) 5.0Ah 360Wh (that little "h" makes all the difference).

Unfortunately, the amps (A) and watts (W) (what we need to know) don't have any direct relation to the Ah and Wh, even though they look similar. Ah is amp-hours, which is capacity. Wh is watt-hours, also capacity, just a different way of stating it. A (amps) is current-delivery ability, and W (watts) is power-delivery ability. Either of the latter two are what we need to know, if we dont' have a rating for the original controller, etc.

Does the mower state how many HP it is? 1HP is about 750W, so that can be used for a guesstimate to pick a controller.

If you had an A (amp) rating for the battery, you could use that, with the nominal voltage (72v) to determine watts, but the amps could be used directly to guesstimate system max current. If you can find the watts, the power limit on the battery, you can calculate backwards with the voltage to get amps. For example, 1000w / 72v = 13.9A.

Kobalt Greenworks 80v Lawn Mower Motor 48v Testing
https://www.youtube.com/watch?v=3OUSs3yd2XY
I found this video, and look like it is a 48v ebike controller making the motor running with come series batteries.
One is from a Greenworks 80v motor with hall sensors like the one in this thread page 3, but he doesnt hook them to anything
motor 3.JPG
Another one is from Kobalt 80V without sensors.
I think this is very promising for what I am doing.

burshless motor.PNG

I also found some brushless motor lokk similar to this mower motor that can be control with the ebike controller.
As noted before, since you don't have sensors on the motor, you can buy a sensorless ebike controller to run it (if it is the right type of motor)
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Re: New 80 volt push mowers

Post by thundercamel » Jan 09 2022 9:48am

If it is a brushless DC 3-phase motor, you could confirm that with some testing. Can you spin the shaft with a power drill? Spin it at a constant speed. Measure AC voltage between all 3 pairs, and the voltage should be the same for all 3.

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Re: New 80 volt push mowers

Post by amberwolf » Jan 09 2022 3:10pm

thundercamel wrote:
Jan 09 2022 9:48am
If it is a brushless DC 3-phase motor, you could confirm that with some testing. Can you spin the shaft with a power drill? Spin it at a constant speed. Measure AC voltage between all 3 pairs, and the voltage should be the same for all 3.
That's a good test I didn't think of. :)
Amberwolf man, you are a blessing to this forum with the sheer number of people I see you helping. Thank you!
You're welcome; I like helping people (at least, those that *want* to be helped and are willing to help me help them ;) ), and at the moment I have more time than usual, am still waiting to see if my job wants me back after my forced leave. If not, I may have a lot less time while looking for a new job (will need one soon either way).

Too bad the forum doesn't have a budget for salaries or I could just do this. :lol:
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Re: New 80 volt push mowers

Post by 99t4 » Jan 09 2022 4:57pm

5net wrote:
Jan 08 2022 5:31pm
On my guess, I believe this is a Brushless DC motor...
Probably don't have to guess, as the photo you displayed states "BRUSHLESS" in all caps:

Image

Now we still haven't discovered the amps so it might be helpful to work backwards from a known similar entity.

As a long time user of corded electric mowers, they are almost always rated at 11-13 amps, 120VAC. Figure the watts at ~1400W. Subtract 15% losses and that gets 1200W.

For the nominal 72VDC battery system that works out to ~17A.

AW please check my work. :wink:

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Re: New 80 volt push mowers

Post by amberwolf » Jan 09 2022 5:20pm

99t4 wrote:
Jan 09 2022 4:57pm
5net wrote:
Jan 08 2022 5:31pm
On my guess, I believe this is a Brushless DC motor...
Probably don't have to guess, as the photo you displayed states "BRUSHLESS" in all caps:
The problem is there are many types of brushless motor, but the cheap ebike motor controllers are only going to work properly on the standard 3-phase types with magnets on the rotor. (and wont' work at all on some other types).
Now we still haven't discovered the amps so it might be helpful to work backwards from a known similar entity.

As a long time user of corded electric mowers, they are almost always rated at 11-13 amps, 120VAC. Figure the watts at ~1400W. Subtract 15% losses and that gets 1200W.

For the nominal 72VDC battery system that works out to ~17A.

AW please check my work. :wink:
It's a good general guesstimate process...but you can still have much higher startup currents for a second , more or less, especially if it's ever started up while sitting on uncut grass.

The ancient B&D corded one I have, that uses a brushed DC permanent magnet motor, is "4HP 13A". 4HP is about 3kw (4 x 750w), though 13A * 120VAC is only about half that. I converted it to battery here:
viewtopic.php?f=7&t=111386&p=1650297&hi ... r#p1650297
to run off 116vDC full, 104V nominal (closest I could get with the spare trike packs I had). The wattmeter used can only handle 60-something volts, so it only monitors half the pack for voltage, but still monitors amps for everything. It shows a peak of 74A, about four times the "rated" current of the mower. The watts reading of 3873W, because it only reads half the voltage, is only half the actual peak of 7746w, whcih makes well over twice what the HP rating is.

I don't know how long that peak lasted, as I can't easily see the meter while using it, but it is certainly high enough to either shutdown or blow up a small ebike controller if the same kind of peak loads could occur on the Kobalt mower.

If we know what the battery itself is physically capable of, we can better guesstimate the maximum possible load the motor could ever be allowed to put on it, at least.
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Re: New 80 volt push mowers

Post by 5net » Jan 09 2022 8:58pm

First, thank you everyone: thundercamel and 99t4, especially you amberwolf for helping me fixing this piece of junk. I just want to make it running, and hopefully this can come out as a cheap way to repair this type of mower.

Second, I believe I found out what type of motor, so I am ordering a 72V 1000W ebike controller. I will let you guys up to date with the process. Please expect more stupid questions from me again...
and last, hopefully I won't set anything on fire anytime soon.
amberwolf wrote:
Jan 09 2022 12:27am
If there are no magnets, a cheap ebike controller probably wont' run it.
If other models use one, it's likely this does too, but can't tell from the pics.
It definitely has magnets inside by turning the blade by hand, I can feel the resistant from the magnets. Also, with thundercamel replied ...
Measure AC voltage between all 3 pairs, and the voltage should be the same for all 3.
so ... its shaft is too big, and I don't have anything to connect to my drill, but by spinning it with my hand multiple times and measuring the voltage of the pair wires, I found out they were all connected and came out *kinda same* voltage every time. :? (hopefully i am not wrong)

In my conclusion, I will say this is a 72V brushless DC 3-phase motor without hall sensors.
I learnt that ebike controller can get a no-hall motor running so I am very positive with ebike controller will work for now.
For the nominal 72VDC battery system that works out to ~17A.
The battery has Samsung 18650-25R cells, they can push out of 20A of max discharge. 72*20 is 1440W, I dont know should I use 1500W controller instead?
On the ebike controller, there is speed control plug that can get the motor at +10% load and as low -30% load.
However, a part of me I dont want anything out of control, so I think I will stick with 1000W for now...
batt 2.jpg
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Re: New 80 volt push mowers

Post by amberwolf » Jan 09 2022 11:48pm

5net wrote:
Jan 09 2022 8:58pm


In my conclusion, I will say this is a 72V brushless DC 3-phase motor without hall sensors.
I learnt that ebike controller can get a no-hall motor running so I am very positive with ebike controller will work for now.
It probably is, and a *sensorless* ebike controller can probably make it work. If you don't get a *sensorless* controller, then it won't work with this motor.

A controller that has a hall connector is not usually sensorless (some are, but they have to say specifically that they can do that), and won't work with this motor.

Just restating it to be sure you don't get the wrong kind. ;)



For the nominal 72VDC battery system that works out to ~17A.
The battery has Samsung 18650-25R cells, they can push out of 20A of max discharge.
72*20 is 1440W, I dont know should I use 1500W controller instead?
On the ebike controller, there is speed control plug that can get the motor at +10% load and as low -30% load.
Assuming the battery is 1P, meaning that all the cells in it are in series, and there are no sets in parallel, then the math is right. However, I see an electronics board in there, which if it is like the typical BMS, itself has a current limit that is usually lower than what the cells can do, so that it can protect them from overloads. So while the cells may handle 20A max, the battery as a whole may not allow that.

But its' a good starting point, so you could go for a 20A continous-current-limit controller.

You can use whatever controller you want to try first, since we have no specific ratings of your mower to base guesstimates on with any kind of certainty. If I were going to "just try one", I would get a 72v 20A sensorless controller (no hall connector) that has no fancy features, just a throttle input, 3 phase output for motor, battery input to power it.

If it has any other features, I'd make sure that they are not required to be hooked up to anything to make the controller work normally at full power, to simplify installation and testing.

If I were to get the controller best for experimenting with this kind of thing, I'd get one that doesn't use the throttle to control speed, but rather to control motor torque (current). That way, I could get a controller that has more power than I might need, but definitely as much as I would need, and then if I find I have problems with motor overheating under heavy loads, I just turn the throttle down, so when engaging the mower it now runs at a lower power level.

There are other ways to handle that kind of problem, too, but that one is really easy. :)

Other methods include programmable current limits, removing one of the shunts if there are multiples, shaving the shunts, (both of these basically lie to the controller to make it think there is more current flowing than there really is). You probably own't need to deal with this issue at all, anyway, but just putting it out there in case you do.




However, a part of me I dont want anything out of control, so I think I will stick with 1000W for now...
If you use a controller that doesnt' have enough power, the mower won't be able to cut as well as it should.

If you use a controller that has more power than you need, the motor will only draw as much as it needs to overcome the load of whatever it is cutting.

If that is a very heavy load, far enough past it's ratings to cause heating in the motor, it might cause problems, but you can monitor temperatures if you like, with whatever kind of thermometer (wired, remote, IR) you have on hand, or can get cheaply and easily. If it gets too hot, just stop mowing till it cools off.

Under normal mowing conditions, you wont' have that problem, even if you use a really big controller, because the motor won't pull too much power.

But it does have to have enough power to do the job it is meant for. ;)




An aside: I don't know if you read what I wrote about power, etc., of the ratings of the mower I have compared to it's actual power usage. While we can't know what power yours will require at startup or under heavier loads, it may also draw the kind of excess power past it's ratings, momentarily. Whether that makes a difference to the controller, we also can't know until it's tested, but I wanted to bring it up, so you can be prepared for the possibility it could cause a problem.
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Re: New 80 volt push mowers

Post by marty » Jan 10 2022 12:27pm

5net wrote:
Jan 07 2022 3:03pm
My 80V Kobalt mower KM 5080-06 just stopped working (no warranty, bought used). Right now, it ran for 3s and then started beeping 3 times repeatedly. So I used another battery to test if it was a defectives battery. Turned out, it was the bad PCB controller board.
I went shopping around and can't find the board: 261013435 anywhere

271444536_632738231399609_8865696529608991633_n.jpg

I wonder if anyone every try to use a controller box from e-bike to make it work around?
https://www.ebay.com/itm/142551852200

Or maybe build a simple circuit to just run it?

Have anyone ever try that?

Thanks.
Re: "Turned out, it was the bad PCB controller board."
Exactly how did you determine that?

Re: "ran for 3s and then started beeping 3 times repeatedly."
After about 2 minutes of research I have discovered Kobalt is Lowe's. Have you called and asked if a service manual exists? Called as in calling repeatedly until you get a intelligent answer to your question. Think the beeping 3 times repeatedly might be trying to speak to you in lawn mower language. Service manual might have beep codes? Is there a shop that fixes these things? Or are they disposable? These are questions that Kobalt / Lowe's people should be able to answer.

If ya haven't? Look here:
KOBALT
21-INCH DECK WIDTH MOWER
ITEM #1129999
MODEL #KM 5080-06


Questions, problems, missing parts? Before returning to your retailer, call our customer
service department at 1-888-3KOBALT (1-888-356-2258), 8 a.m. - 8 p.m., EST,
Monday - Friday.

Also see:
5-YEAR LIMITED WARRANTY

In you picture on page 5. See 01/16/19

According to my math. Mower is less then 5 years old.

What I would do if I needed a machine to cut grass. Put mower all back together. Hike over to Lowe's and lie with a sad look on your face. Explain that your grandpa just died from Covid and grandma is crying and searching for the receipt. 99.99% sure that she will never find receipt. Bet they give you a new mower :) Or tell you to take it to a local mower fix it shop. Repair or replace under warranty.

I used to work at Home Depot. Someone bought 50 pails of roof coating tar. It rained and his roof leaked. He returned 50 empty pails of roof tar. Got all his money back. Home Depot people then had to figure out how to dispose of 50 empty pails of roof tar with hazardous waste tar in them.

What I would do if I wanted to learn about motors and controllers. See if you can make the motor spin. There is a whole lot I don't know about brushless motors but I like to learn.

Note from manual I link to:
2. Soft-Start
This mower is equipped with a “soft-start” feature. When initially starting up, the mower will take ap-
prox. 3 seconds to get up to full speed. If the mower does not initially start: Remove the
battery and check under the mower deck to ensure there is nothing obstructing the blade and that the
blade can spin freely by hand. Even a small amount of grass on start up will prevent the “soft start”
from turning the mower on.

Since you said "it ran for 3s" Wondering if controller is OK but motor might need a cleaning and a drop or two of oil? Motors get buggered up. Also clean grass from bottom of deck. Wear a N95 dust mask when working with moldy dry grass. After breathing in way too much lawn mower dry moldy grass I have felt like bad respiratory the next day. Wetting anything dry and hazardous will prevent it from going into your lungs.

Also when playing with electric mowers, I have seen a switch where grass exits. Need bag, mulch cover, or shoot to be attached or blade NO spin. This is to prevent blade from cutting your toes off. All kinds of safety switches on these things. Switches could be normally closed. normally open, or normally I don't know. NC, NO, or NIDK.
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Re: New 80 volt push mowers

Post by 5net » Jan 10 2022 1:21pm

marty wrote:
Jan 10 2022 12:27pm
Exactly how did you determine that?
I bought another new battery to test it. It does exactly the same: "run 3s, then beep-beep-beep ... beep-beep-beep"
Have you called and asked if a service manual exists? Called as in calling repeatedly until you get a intelligent answer to your question. Think the beeping 3 times repeatedly might be trying to speak to you in lawn mower language. Service manual might have beep codes? Is there a shop that fixes these things? Or are they disposable? These are questions that Kobalt / Lowe's people should be able to answer.
I bought this mower out from a liquidation pallet. I think somebody bought it, not working, then they returned, and finally somehow ended up on my hand for $50. It is a brand new mower in the box, never used. The wheel, blade, the bottom are clean, no sight of used.
All manuals are still inside the box. Nothing mention to do trouble-shooting. What you said with the manual is exactly what I was expected when I bought it. Turnout, no luck for me. Not a lot info online about either. Trust me! You are not the only know how to use google or "do searching".
In you picture on page 5. See 01/16/19
It's on the battery. By the way, they have serial number on every components.
What I would do if I needed a machine to cut grass. Put mower all back together. Hike over to Lowe's and lie with a sad look on your face. Explain that your grandpa just died from Covid and grandma is crying and searching for the receipt. 99.99% sure that she will never find receipt. Bet they give you a new mower :) Or tell you to take it to a local mower fix it shop. Repair or replace under warranty.
Well, it has its Serial Number, I don't see how we can *baby cry* to get Kobalt talk to me. They only talked if only you can confirm that you are the "original purchased owner", as it mention almost everywhere.
Plus, I don't want to lie to just get what I want.
I used to work at Home Depot. Someone bought 50 pa
...
about motors and controllers.[/color][/i][/b] See if you can make the motor spin. There is a whole lot I don't know about brushless motors but I like to learn.
Have you ever try to call Kobalt number? They are horrible ... waiting time is hours.

Since you said "it ran for 3s" Wondering if controller is OK but motor might need a cleaning and a drop or two of oil? Motors get buggered up. Also clean grass from bottom of deck. Wear a N95 dust mask when working with moldy dry grass. After breathing in way too much lawn mower dry moldy grass I have felt like bad respiratory the next day. Wetting anything dry and hazardous will prevent it from going into your lungs.

Also when playing with electric mowers, I have seen a switch where grass exits. Need bag, mulch cover, or shoot to be attached or blade NO spin. This is to prevent blade from cutting your toes off. All kinds of safety switches on these things. Switches could be normally closed. normally open, or normally I don't know. NC, NO, or NIDK.
It's new, and I did a teardown, almost every single parts are out out. No switch as you mentioned.
I bought it for cheap to play with it cause I want to spend my time to learn during the winter.

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Re: New 80 volt push mowers

Post by 5net » Jan 10 2022 1:50pm

amberwolf wrote:
Jan 09 2022 11:48pm
It probably is, and a *sensorless* ebike controller can probably make it work. If you don't get a *sensorless* controller, then it won't work with this motor.
Yes, I did look around for a sensorless controller and only find 1 for ~$35 which is the same price with a ebike controller with "Product Description: The product according to market demand to do without Hall zero start, brushless dual-mode smart measure battery voltage, motor phase!"
Assuming the battery is 1P,
...
But it does have to have enough power to do the job it is meant for. ;)
I found out that Kobalt battery is limited at 5A max discharge. Also, ther are some selling custom parts that help the battery push out more with max 15~20A, so people do try to use this battery for e-bike. I dont think the discharge of this battery is normally at 20A.
I do have one "control motor torque (current)" speed control switch, and I will use it at first.
Also, I can't not figure it out yet how to re-use the bail-clever and safe button to use with the ebike controller.
"Two ways to start:
1. hold button A and pull bail B
2. Pull bail B and press button A" (then I can release the button A)
with 3 wires coming out, in my guess is 1 of the wire is sending to signal to light up the battery indicator at the button.
The battery indicator has 5 wires. What do you think?
An aside: I don't know if you read what I wrote about power, etc., of the ratings of the mower I have compared to it's actual power usage.
Sorry, I did read every your wrote over and over again, I am taking note when I have a chance to do some test and let you know.
So far, the only part that I will try to replace is the controller, everything is there: battery, switches, motor. The ebike controller have 3 speed dial, I will play round to find out what is the best speed to run it.

When it started to run for 3s, it actually gave a big torque that twisted the body of the mower a little bit, and since it doesnt have a hall sensor. I assumed that is a "ok" and not worry much about.
we also can't know until it's tested, but I wanted to bring it up, so you can be prepared for the possibility it could cause a problem.
And yes, like you said, we dont know anything until I can test it.
By the way, I dont mind to set it on fire, with fireworks and big sparks. Or at least, I will want to keep all of my fingers, and no fire.

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Re: New 80 volt push mowers

Post by amberwolf » Jan 10 2022 4:51pm

5net wrote:
Jan 10 2022 1:50pm
Yes, I did look around for a sensorless controller and only find 1 for ~$35 which is the same price with a ebike controller with "Product Description: The product according to market demand to do without Hall zero start, brushless dual-mode smart measure battery voltage, motor phase!"
If you link to it, I can see if it says anything on the page that indicates it may not work, or anything that helps us figure out a good wiring diagram/etc for you to hook it up to the mower. :)

BTW, I re-read the description of the controller you previously linked to, and it does actually support sensorless mode; they just have a badly-translated phrasing for it:
https://www.ebay.com/itm/142551852200
Double-Mode, controller can check the motor hall sensor condition automatically. If the motor sensors are broken, controller will operate to None-Hall mode.
"None-Hall mode" means sensorless. ;)
That controller's description (where I foudn the above) specifies it's actually the 84v version. You probably want the 72v version it links there (this is the 1000w, they also link a 1500w)
https://www.ebay.com/itm/302033173933
because your battery is nominal 72v, and that's what that means on the controller specs. :)

It also says
First look at your e-bike battery voltage levels, corresponding to the selected voltage controller, look at the size of the current controller previously used, such as the 16A-18A 350W controller, 22A-24A controller is 450W, 28A -30A controller is 500W, 31A-33A is 600W controller, 33A-35A is 800W controller, 36A-38A is the 1000W controller, 40A-43A is the 1200W controller, 50A is about 2000W controller. If the original e-bike is 350W we recommend upgrading to a faster wattage, so you can take advantage of the best motor speed and power.
whcih all comes down to that the 1000w controller probably has a current limit of 36-38A, which is way higher than what your battery supports, so if the motor gets bogged down a lot while mowing, it could draw more current than the battery can safely output (more on that later in the post where you mention battery info). There are ways to lower this if necessary by manually modifying the controller inside, for many controllers.




I found out that Kobalt battery is limited at 5A max discharge. Also, ther are some selling custom parts that help the battery push out more with max 15~20A, so people do try to use this battery for e-bike. I dont think the discharge of this battery is normally at 20A.
If the battery is limited to 5A max, then that means the most power the mower could possibly draw from it when it's charged to 80V is only 5A * 80V = 400W, and past that the battery would shut itself off, if it has a protection board in it that does this.

If it relies on the mower to do the shutoff, which some of the power tool/battery systems out there do, then without the original controller the only limiting that will happen is whatever the new controller is able to do on it's own). In that case, you would need a controller that has a very low current limit (5A), to keep the batteries at the limit they would have been at originally.

If the battery doesnt' ahve any internal protection or fuses to keep it from supplying up to the 20A the cells can do, then you can try using them with a higher-current-limit controller, up to the 20A. If there is a fuse or other protection you don't know about on them that is below the limit of what the motor actually makes the controller pull from the battery, the fuse will blow or the protection will engage and the battery will stop working. (some of these protections self-reset, some reset when put back on the charger, and some are permanent "bricking" of the battery).

You can also bypass the protection, fuse, etc. if you have to, but this may prevent using the Kobalt charger (and/or using it with an other Kobalt tool).

I do have one "control motor torque (current)" speed control switch, and I will use it at first.
Just so you know, a switch doesn't actually do anything but switch things; it doesn't actually change motor torque or current, unless it is supported by the controller itself, no matter what the switch itself is called. ;)

If you already have a sensorless ebike controller, that doesn't directly control the current (most don't, just the speed), then the switch doesnt' do what it says, it just controls the speed (assuming the ocntroller itself supports even that (not all do)).

Also, I can't not figure it out yet how to re-use the bail-clever and safe button to use with the ebike controller.
"Two ways to start:
1. hold button A and pull bail B
2. Pull bail B and press button A" (then I can release the button A)
with 3 wires coming out, in my guess is 1 of the wire is sending to signal to light up the battery indicator at the button.
It depends on how the switches work.

1 Set your multimeter to continuity or 200ohms. Put red lead on first pin of the switch connector that goes to the switches. PUt black lead on the next pin. The meter should beep or read a very low number for a connection, and OL (or whatever your meter manual says) for no connection.

2 While measuring that first wire pair, activate the bail and note the results.

3 Deactivate the bail and activate the safe button, and note the results.

4 Move the red lead to the next pin, and repeat #2 and 3.

5 repeat this until all combinations of pins have been tested and noted.

Now you have a chart that shows you which pins are connected or disconnected by activating or deactivating each of the two switches.

There is probably one common wire between them, and one wire that is the "signal" for each switch. If so, you may only be able to use one of the switches, unless you rewire each switch to be independent two wires. Depends on what you want to use them for.

If the bail is the hand control used to start the mower, then that is the one you use to pass the throttle's output signal wire to the controller's throttle input wire.

If the bail is just another safety switch, and you have a separate hand control switch to activate the mower, and the bail and safety button are wired to the same 3-pin connector with a common wire between them, and they both are "NC" or Normally Closed switches (shorted except when pressed or "on") then you can wire them both to the Ebrake input of the controller, so that they keep the controller disabled except when the safetys are turned off.

Using alligator clip leads will help hold them in place if you need more hands; there are also holders called "helping hands" that even harbor freight carries that help you hold stuff while you work on it.


If you can, I would recommend drawing up a wiring diagram for the parts on the mower as you test them, in a way that you will understand and be able to refer to as you change out and connect the new controller and do testing, etc. Then if you need to fix things later you also have something to refer to without having to remember why things are wired the way they are. ;)



The battery indicator has 5 wires. What do you think?
The battery indicator 5 wires are probably four individual wires to each LED, plus a power or a ground, if there are four LEDs. There are battery meter chips out there you can buy and wire up to re-use them, but you do have to build some other circuitry around that to make them work.

If it uses something else, I'd need to know what that is before I could make much of a guess. You'd need to get pics of the actual battery indicator board, if it's accessible, for us to see what electronics it has on it (if any) to help determine how you might re-use it (if it's possible; which it probably is).

Originally the controller drove the indicator in some way, which makes sense since it has to have an MCU on it to do the motor controlling anyway. (if not driven by the MCU, it's probably a separate battery meter/indicator chip on the controller board, under that potting).

It is probably easier and cheaper to buy a separate battery meter, or use one already mounted in a throttle.

So far, the only part that I will try to replace is the controller, everything is there: battery, switches, motor. The ebike controller have 3 speed dial, I will play round to find out what is the best speed to run it.
The "speed dial" in most cases only changes the amount of voltage going to the mower motor (and blade), not the power going to it. Generally, you want the speed of the blade to remain at the same speed so it cuts correctly, and moves the cooling fan for the motor (if it has one; it's common) at the right speed to move enough air to keep it cool.

If you want to control the power of the motor, the controller has to be designed to actually be a torque/current control type (FOC controllers do this, but so do some "regular" controllers, in a different way), and that switch has to actually change what current the controller provides to the motor. Typical cheap bike controllers don't do this; just change the speed.

Changing the speed does change the power used, but it also changes the speed.

Changing just the current limit to the motor doesn't change the speed of the motor, *except* when the power needed by the motor to maintain that speed (like when hitting heavy grass, etc) is greater than the limit. So for this purpose, it's a more effective way to prevent motor overheating, excess battery drain/load, etc. :)

When it started to run for 3s, it actually gave a big torque that twisted the body of the mower a little bit, and since it doesnt have a hall sensor. I assumed that is a "ok" and not worry much about.
Most likely it means the motor is fine (since it gave you the voltages on the wires when you tested it spinning, it also means i'ts probably fine).
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Re: New 80 volt push mowers

Post by marty » Jan 11 2022 8:48pm

Wondering if Kobalt and Greenworks mowers are related? Related as in share some parts. Lets do some research.
https://everythingwhat.com/are-kobalt-a ... s-the-same
Greenworks 80V and Kobalt 80V yard tools are made by Global Tools using the same design, with slight branding changes.
This mower looks similar to Kobalt KM 5080-06

Greenworks Pro 80V 21" Brushless Lawn Mower w/ 4.0 Ah Battery
Model 2501202
https://www.greenworkstools.com/pro-80v ... er-2501202

Also sold at Lowe's.

Here is link to manual.
https://www.greenworkstools.com/media/c ... 1602_E.pdf

See EXPLODED VIEW on page 30

Item No. 4, PCB board 362011179

Here is link to PCB board 362011179 for sale.
https://greenworks.ordertree.com/sun-362011179.html
In Stock
$87.33
PCB BOARD (2500402)

Note that this same part as discussed on page 3 of this topic:
viewtopic.php?f=1&t=79384&start=50#p1221623

Might have better luck replacing a lawn mower PCB board with a lawn mower PCB board rather then a electric bicycle controller.
Matteo's Mobile Bicycle repair
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Re: New 80 volt push mowers

Post by 5net » Jan 13 2022 3:34pm

amberwolf wrote:
Jan 09 2022 11:48pm

Presumably the hand control you ahve now does not change the motor's speed, and only goes either full on, or off. If that's the case, you can use a potentiometer between the hand control and the controller's throttle input to fake an ebike controller into going full speed without getting any errors from not having an actual throttle. We'll worry about that after figuring out which controller will work for your system.
I had the 72V 1500W controller on hand now. This is what I am connecting:

Battery Power (+) red to Controller (+) red (and Switch plug (+) small red)
Battery Power (-) black to Controller (-) black


Controller motor A green to Motor brown
Controller motor B yellow to Motor yellow
Controller motor C blue to Motor black

and that's it, I dont know to get the throttle to send on signal to the controller:

Red - is 5V
Green - is 0.6V to black?
Black - ground

How do I get it run max without buying a throttle?
Last edited by 5net on Jan 14 2022 2:52pm, edited 2 times in total.

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Re: New 80 volt push mowers

Post by 5net » Jan 13 2022 3:39pm

marty wrote:
Jan 11 2022 8:48pm
Wondering if Kobalt and Greenworks mowers are related? Related as in share some parts. Lets do some research.
https://everythingwhat.com/are-kobalt-a ... s-the-same
Greenworks 80V and Kobalt 80V yard tools are made by Global Tools using the same design, with slight branding changes.
This mower looks similar to Kobalt KM 5080-06

Greenworks Pro 80V 21" Brushless Lawn Mower w/ 4.0 Ah Battery
Model 2501202
https://www.greenworkstools.com/pro-80v ... er-2501202

Also sold at Lowe's.

Here is link to manual.
https://www.greenworkstools.com/media/c ... 1602_E.pdf

See EXPLODED VIEW on page 30

Item No. 4, PCB board 362011179

Here is link to PCB board 362011179 for sale.
https://greenworks.ordertree.com/sun-362011179.html
In Stock
$87.33
PCB BOARD (2500402)

Note that this same part as discussed on page 3 of this topic:
viewtopic.php?f=1&t=79384&start=50#p1221623

Might have better luck replacing a lawn mower PCB board with a lawn mower PCB board rather then a electric bicycle controller.
I already looked around with that. I think that Greenworks motor have hall-sensors and self-propelled with it, also plus shipping out is $100, the rest of them are out of stocks. Not too crazy, but that is not what I am trying to achieve anyway.

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Re: New 80 volt push mowers

Post by amberwolf » Jan 15 2022 2:37am

5net wrote:
Jan 14 2022 10:36pm
Battery Power (+) red to Controller (+) red (and Switch plug (+) small red)
Battery Power (-) black to Controller (-) black
That should be right.
Controller motor A green to Motor brown
Controller motor B yellow to Motor yellow
Controller motor C blue to Motor black
It shoudln't matter what color is which. If it spins backwards once you get it working, just swap any two of those wires and it will spin the other way. :)
Red - is 5V
Green - is 0.6V to black?
Black - ground
If this is describing the controller's throttle connector, then red and black should be those, and you should get 5v from the red wire whenever the battery wires are connected as noted above.

The green wire for a hall throttle signal input (probably what this controller expects) needs a specific voltage range to activate it. Usually throttle off is around 1v or less, then anything from that to around 4v spins the motor, at increasing speed the higher the voltage, then above around 4v it may have a shutdown error to prevent runaway operation if the ground wire breaks or the throttle malfunctions, etc. Similarly, if the throttle voltage is higher than the minimum (off) voltage when the controller is turned on, it may shutdown for similar reasons.

and that's it, I dont know to get the throttle to send on signal to the controller:
<snip>
I can't send the signal to the bike controller without using the throttle.
How do I get it run max without buying a throttle?
I'm not sure exactly what you mean. This line:
I dont know to get the throttle to send on signal to the controller:
implies you have a throttle but that it's not sending the right signal (or perhaps any signal) to the controller, but that conflicts with the last line.

If you don't have a throttle, or a voltage divider, or a potentiometer, to create the right voltage for full throttle for that controller's specific throttle signal input voltage range (often marked on the casing, or in the specs for the controller on the sale page, but not always), then you'll have to get or make one of these things to do so.

If you do have a throttle of the right type for teh specific controller, it has to be wired so that the controler provides it 5v on the right wire (probably red) and ground (battery negative) on the right wire (probably black). Then the throttle output signal wire of the throttle connects to one side of whatever switch is used for the hand control of the mower, and the throttle input signal wire of the controller connects to the other side of that switch.

That assumes the switch is a normally-open type, so that the switch is closed (connects) when you engage the hand control. If it is a normally-closed type, or is not a switch, then you'll have to install a switch to use for this, or replace teh one that's in there.


If you need to make a voltage source for the throttle input without making one, you can first just try using the 5v line as the input to the hand control switch wire. If the controller won't work, or shuts down immediately, then you probably need a voltage divider (or pot, or throttle) to provide a lower voltage to the throttle input of the controller, at but not beyond whatever it's max input is.

The simplest way is with a hall type throttle, because it's what these controllers are usually designed for so there's no messing around to make it work.

The next simplest is a 5kohm to 10kohm potentometer (pot). One side wires to the controller ground. The other to the 5v. The center goes to the hand control switch wire that the throttle signal would go to.

To set up the pot, hold the hand control in it's on position, then adjust the pot until the motor spins fastest without shutting down. Let go of the hand control, and leave the pot at that setting and secure it somewhere.


voltage divider is hardest, because you'll have to calculate two resistor values that will give you the right voltage, then buy the closest values you can get to those.
If you found this advice helpful, supporting contributions are accepted here.

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Re: New 80 volt push mowers

Post by softwarecrash » Jan 17 2022 6:49am

Hi there,
I have various Greenworks devices that I would like to use with other batteries.
I looked at the signal and wrote a small program based on it.
the program is designed in such a way that you can easily use other battery types.
unfortunately i don't have 60v and 80v batteries and can't reproduce the signal for them.

since the signal pauses are always the same length, i only need the pulse lengths and number of pulses, and what for battery and manufacturers.

Like this:
Screenshot 2022-01-17 205224.png
Screenshot 2022-01-17 205224.png (17.88 KiB) Viewed 313 times
like 1x400 3x200 13x102 .....

then i can include it in the program, maybe we can create a list with which manufacturers and battery types it works?

here the program
https://github.com/softwarecrash/OmegaFaker

sorry for the bad english, greetings from germany

PS: adapted @plmicia signal timings for Powerworks 60V and from @StinkyGoalieGuy for Greenworks 60V, can anyone confirm that it work?

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Re: New 80 volt push mowers

Post by marty » Jan 20 2022 7:24am

amberwolf wrote:
Jan 15 2022 2:37am
5net wrote:
Jan 14 2022 10:36pm
Battery Power (+) red to Controller (+) red (and Switch plug (+) small red)
Battery Power (-) black to Controller (-) black
That should be right.
Controller motor A green to Motor brown
Controller motor B yellow to Motor yellow
Controller motor C blue to Motor black
It shoudln't matter what color is which. If it spins backwards once you get it working, just swap any two of those wires and it will spin the other way. :)
Red - is 5V
Green - is 0.6V to black?
Black - ground
If this is describing the controller's throttle connector, then red and black should be those, and you should get 5v from the red wire whenever the battery wires are connected as noted above.

The green wire for a hall throttle signal input (probably what this controller expects) needs a specific voltage range to activate it. Usually throttle off is around 1v or less, then anything from that to around 4v spins the motor, at increasing speed the higher the voltage, then above around 4v it may have a shutdown error to prevent runaway operation if the ground wire breaks or the throttle malfunctions, etc. Similarly, if the throttle voltage is higher than the minimum (off) voltage when the controller is turned on, it may shutdown for similar reasons.

and that's it, I dont know to get the throttle to send on signal to the controller:
<snip>
I can't send the signal to the bike controller without using the throttle.
How do I get it run max without buying a throttle?
I'm not sure exactly what you mean. This line:
I dont know to get the throttle to send on signal to the controller:
implies you have a throttle but that it's not sending the right signal (or perhaps any signal) to the controller, but that conflicts with the last line.

If you don't have a throttle, or a voltage divider, or a potentiometer, to create the right voltage for full throttle for that controller's specific throttle signal input voltage range (often marked on the casing, or in the specs for the controller on the sale page, but not always), then you'll have to get or make one of these things to do so.

If you do have a throttle of the right type for teh specific controller, it has to be wired so that the controler provides it 5v on the right wire (probably red) and ground (battery negative) on the right wire (probably black). Then the throttle output signal wire of the throttle connects to one side of whatever switch is used for the hand control of the mower, and the throttle input signal wire of the controller connects to the other side of that switch.

That assumes the switch is a normally-open type, so that the switch is closed (connects) when you engage the hand control. If it is a normally-closed type, or is not a switch, then you'll have to install a switch to use for this, or replace teh one that's in there.


If you need to make a voltage source for the throttle input without making one, you can first just try using the 5v line as the input to the hand control switch wire. If the controller won't work, or shuts down immediately, then you probably need a voltage divider (or pot, or throttle) to provide a lower voltage to the throttle input of the controller, at but not beyond whatever it's max input is.

The simplest way is with a hall type throttle, because it's what these controllers are usually designed for so there's no messing around to make it work.

The next simplest is a 5kohm to 10kohm potentometer (pot). One side wires to the controller ground. The other to the 5v. The center goes to the hand control switch wire that the throttle signal would go to.

To set up the pot, hold the hand control in it's on position, then adjust the pot until the motor spins fastest without shutting down. Let go of the hand control, and leave the pot at that setting and secure it somewhere.


voltage divider is hardest, because you'll have to calculate two resistor values that will give you the right voltage, then buy the closest values you can get to those.
How's the lawn mower spinning? Fun places to look at electronic gizmos and magic to fool controller with fake throttle.
https://www.newark.com/
https://www.mouser.com/
https://www.alliedelec.com/

They might have technical on the phone help.

If it smokes. You got a problem.
Last edited by marty on Jan 20 2022 7:51am, edited 1 time in total.
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Re: New 80 volt push mowers

Post by marty » Jan 20 2022 7:31am

5net wrote:
Jan 13 2022 3:39pm
marty wrote:
Jan 11 2022 8:48pm
Wondering if Kobalt and Greenworks mowers are related? Related as in share some parts. Lets do some research.
https://everythingwhat.com/are-kobalt-a ... s-the-same
Greenworks 80V and Kobalt 80V yard tools are made by Global Tools using the same design, with slight branding changes.
This mower looks similar to Kobalt KM 5080-06

Greenworks Pro 80V 21" Brushless Lawn Mower w/ 4.0 Ah Battery
Model 2501202
https://www.greenworkstools.com/pro-80v ... er-2501202

Also sold at Lowe's.

Here is link to manual.
https://www.greenworkstools.com/media/c ... 1602_E.pdf

See EXPLODED VIEW on page 30

Item No. 4, PCB board 362011179

Here is link to PCB board 362011179 for sale.
https://greenworks.ordertree.com/sun-362011179.html
In Stock
$87.33
PCB BOARD (2500402)

Note that this same part as discussed on page 3 of this topic:
viewtopic.php?f=1&t=79384&start=50#p1221623

Might have better luck replacing a lawn mower PCB board with a lawn mower PCB board rather then a electric bicycle controller.
I already looked around with that. I think that Greenworks motor have hall-sensors and self-propelled with it, also plus shipping out is $100, the rest of them are out of stocks. Not too crazy, but that is not what I am trying to achieve anyway.
Re: "Greenworks motor have hall-sensors" Is that statement based on fact or speculation? I suspect Greenworks and Kobalt are more the same rather then different. Like Buick and Chevrolet.

Re: "self-propelled" Incorrect. Unless I an reading wrong. The mower I linked to is not self-propelled.
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Re: New 80 volt push mowers

Post by marty » Jan 20 2022 7:50am

I am not convinced that a beeping noise means that lawn mower is broke. Could mean that is not happy about something and it is trying to send a message. Look at this video.

I really really want to look at a service manual for these mowers. Wondering if there is some reset procedure? Example - Remove battery, install battery, turn off and on 3 times, rub nose, say prayer, Now it works.

Instead of looking at the internet and watching stupid videos of idiots who don't know what a service manual is. Try this.

https://greenworks.ordertree.com/dealerlocator

Local Lowe's people know which shops fix what.

Find a local lawn mower repair shop. Those people are called Small Engine Repair Guys. Ask if there is a service manual for your beeping lawn mower. Be ready to bribe. Small Engine Repair Guys like money, prostitutes, fruit, or anything of value.

Rant about trying to fix stuff without a service manual. Would you go to a doctor who never read a book?
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Re: New 80 volt push mowers

Post by Warren » Jan 20 2022 11:23am

marty wrote:
Jan 20 2022 7:31am
I suspect Greenworks and Kobalt are more the same rather then different. Like Buick and Chevrolet.

Re: "self-propelled" Incorrect. Unless I an reading wrong. The mower I linked to is not self-propelled.
I started this thread back in 2016. After checking out our neighbor's push 80 volt Greenworks mower, we bought one ourselves. It is still going strong, as is the matching weed whip, and chainsaw.

You are correct. Kobalt is Lowes store brand. The original Kobalt were made by the same company in China as the Greenworks. Don't know about current Lowes branded mowers. Haven't spent much time in Lowes since the pandemic.

Greenworks makes push, and self-propelled, versions of the 80 volt mower. With the pandemic, supplies of everything are pretty spotty. Tried to buy our chainsaw direct from Greenworks, but they were temporarily out of stock. Amazon, of course, had lots of sellers with them.

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Re: New 80 volt push mowers

Post by Warren » Jan 20 2022 11:33am

The chainsaw is pretty amazing. I was a bit skeptical when I first ordered it, after wind storms last year, as the hp/wattage is way less than my old gas chainsaw was. But the torque of an electric motor makes all the difference. We were at the epicenter of the recent Virginia snowmageddon. Our place looked like Siberia, after the Tunguska asteroid. I was amazed at how well that thing cut up downed trees.

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