UPDATE! Very interesting to say the least. As many of the video's on utube have found. Water is the demon and some darn how way it gets inside the so called protective metal box. However moving forward...and funny even me in this tread is now moving away from the motor topic to the controller and other factors! LOL...mainly because without the controller there's not much of a way to test the motor alone as to see if it's still good and works. But...the motors are actually very not likely to be an issue on these anyway. On these lawnmowers there are safety switches/sensors and they are known to be an issue at times making the Controller not do it's job.."in the name of safety" they say. It's very wise to give these a look. Found that they are using black as a loop like they use white on lawntractors...then the other wires are color coded, one color for the safe bar(on/off) start button, speed, and if have power wheels. It pays to know the colors as they go to the controller and then it's clear how the board in the controller is running the machine. The really cool part of this is....ebay through china...u can buy a controller for under 20.00!! but U must know your wire hookups! While on ebay another really cool thing is they selling a box tester that tests controller, Hall, Motor and more! that's like 12.00 and it's mainly made for E bikes. I'm buying the cheap controllers and "hard wire" them in for their use and will most likely be able to keep all the "safety" intact! Note, if U have self propelled there will be two boards...one is a driver board for the self propelled motor and then the normal controller for blade motor and it's safety on off stuff. If U are a quick study U will figure out how it all works in no time, having the circuit board exposed helps greatly! I still have one baffle to solve. It's that tiny single wire from the 40volt battery. Of course there's the red thick for positive..and the black thick for negative...that's easy. but this tiny orange wire goes alone to the circuit board ...I thought it was for overheat and it would shut things down till it cooled...but then I noticed in cordless tools it would power the led light. I wonder if perhaps it "powers" the other side of the circuit board like maybe 5v so other things can work or function and no transformer is needed to break down the 40v??? Still looking for this answer as of yet.... Thanks all for your two cents....it was worth more than that!

Hey 6

 

This has me confused also. I have a DeWalt 40 vdc.electric lawn mower that after having a few problems with as the key switch and a internal safety causing the controller not to function. I desided to bypass every thing and run the motor off a toggle switch. Being done, I have a three wire motor that I can not start up being I'm not using the controller.. What is up with these 3 wire DC voltage motors. I can't find a wiring diagram for the motor so Im back to the problem of wiring this motor.
Any Help?

 

A brushless DC motor is not likely to ever function without a controller to produce the electronic commutation. Not EVER!!
So you need to use the controller but with some of those "safety" circuits bypassed. At that point you do need to understand that it will no longer be fool-proof, and potential hazards will exist. It will no longer stop if you try to put your hand in the blade, or mow over your foot. In the condition of safety interlocks bypassed, that defeat natural selection, the operator is now the only one responsible for their safety. So full-time, 100% attention is required. And I fully understand that some folks will never ever even think that they must be attentive and focused on what they are doing.

 

This has me confused also. I have a DeWalt 40 vdc.electric lawn mower that after having a few problems with as the key switch and a internal safety causing the controller not to function. I desided to bypass every thing and run the motor off a toggle switch. Being done, I have a three wire motor that I can not start up being I'm not using the controller.. What is up with these 3 wire DC voltage motors. I can't find a wiring diagram for the motor so Im back to the problem of wiring this motor.
Any Help?

It was all covered and explained over a year ago in the original thread.
As stated, the same, virtually identical motor covers both BLDC and 3ph AC Electrically Commutated Motors.
IOW, they both require a controller that can interpret the timing of the commutation signal(s).
The simpler, common 3ph motor is self commutating through an induced 3ph signal into its squirrel-cage rotor.
Hence Induction Motor.

 

LIKE MAX SAYS!! A three wire motor in a battery powered device MUST HAVE that controller. You can bypass the various "safety" switches and trick the controller, but you must have some system to provide electronic commutation.

 

Just to add, there are some PM rotor motors that use auto detection for rotor position. Rather than use external devices.
The motor at power on, exercises the rotor and from this determine the stator to rotor relationship. after which, all subsequent positions are know, as long as power is not removed.

 

If exact motor position is not required, why not just run open loop???start rotating the fields and in no time at all the motor will lock in step. Right, Max??

 

There are typically two types of commutation for PM rotor motors, although the motors are identical in construction, the difference is in the commutation, either BLDC or PMSM.
An excellent paper that describes both is below.

 

Once again, regardless of which commutation scheme the motor requires, that controller is needed to make it run at all. So while you could bypass all of those interlock switches, THERE IS NO WAY that you can run a BLDC motor without the controller module.

Wanting it to be possible will not make it happen. No matter how hard you wish it would.

 

This has me confused also. I have a DeWalt 40 vdc.electric lawn mower that after having a few problems with as the key switch and a internal safety causing the controller not to function. I desided to bypass every thing and run the motor off a toggle switch. Being done, I have a three wire motor that I can not start up being I'm not using the controller.. What is up with these 3 wire DC voltage motors. I can't find a wiring diagram for the motor so Im back to the problem of wiring this motor.
Any Help?

Hi Any luck on what you're trying to do am in the same boat and could use some advice