Troubleshooting - One Phase of Motor Not Firing After Crash

[jeremy]

I am a very satisfied owner of a Golden Motor 48v motor/controller electric bike kit, but I am in need of some help to get my bike up and running again.

I foolishly left slack on the lead to the motor at its axle, leaving it completely unprotected and paving the way for a minor personal-transportation disaster, which left me stranded miles from home (though, thankfully, uninjured).  This was an easy mistake to make and I am sure, if it is not already a common issue for the electric bike DIY'er, it will be in the future as alternative means of transportation become more popular.

While riding over uneven concrete, I fell and the bike slid on its side, crushing and severing the wires running from the motor axle to the controller.  Repairing the damaged wires was straightforward, but now one of the three phases of the motor appears not to be firing.  You can view some footage of my problem at YouTube to see for yourself:

   http://youtube.com/user/hiptahop

There are no outward signs of damage to the controller or motor, both of which I disassembled to inspect.  I should say my inspection, without a tech background, was limited to smelling for burned-out components, looking for loose wires, and basically just checking for any obviously broken stuff.

Based on the small amount of information I was able to gather online, I guess the problem lies with either a failed hall-effect sensor on the motor or the controller board itself.  But I don't know how to figure out which part is giving me the problem... or if it is something else entirely.

How should proceed to fix my bike?

[myelectricbike]

You can build a firing order table by powering only the sensor supply leads with +5 volts (red is the positive lead), monitoring the sensor outputs with 3 meters (volt meters) and slowly turning the wheel.

Since the Golden hub has 46 magnets you will need a table with 46 rows. I use an Excel spreadsheet to build my tables but you can use paper just as well.

Make four columns, one to list the switch point number (1-46), one for the green sensor output lead and one each for the blue and yellow leads. The order of the columns does not matter at this point.

With the sensors powered and the outputs monitored slowly turn the wheel until there is a voltage transition on any one of the sensor output leads (should be every 7.82 degrees). Record the voltage transition as either going from 5 to 0 or form 0 to 5 volts. (record the actual output transition voltage for each sensor - 5 is max 0 is minimum)  ...0 to 4.5 is recorded as 4.5. 4.5 to 0 is recorded as 0. Do all 46 rows.

You can email the table to me for analysis but it should be obvious what and where the problem is.

[29a]

It looks like a bad/intermitant connection or maybe one broken hall sensor wire.

I don't have this controller yet so this is based on another controller
but the method should be the same the voltages may be different

note if you do open up the controller the parts are static sensitive so take all precautions.

You will need a electrical meter that can read DC volts and ohms
Here are some tips on checking the motor status open up the controller find five small wires that go to motor these are the hall effect wires

 (1) Make sure there is power in the sensors
Check Supply Voltage to sensors, hopefully should be a red (positive) and black (negative) wire if no red and black check them all and find the neg and positive

#1 : Positive

#2 : Negative


1. Turn the throttle on while checking the sensor voltage between #1 and #2

It is not necessary to connect the 3 motor phase power wires

If the Voltage is between  7 volt - 9 volts this good

If there is no voltage between #1 and #2

check the following

1. Some cables  are not connected well , For example battery cable or hall effect plug gently test the wires on the hall effect plug to see if they are loose.

2. The speed controller may have failed

3. There may be a short circuit in the wiring


(2) Check 3 sensor's condition (the other 3 small wires)
- Check sensor's wire condition, What to know Are there any broken or disconnect??

1. Turn on the throttle check each wire to negative

2. The 3 motor phase power wires do not need to be connected

3. Rotate the wheel or motor hub by hand while checking the voltage from wire to negative sensor power.

Status in Voltage :

The voltage will change from 0 v to 13 v as the wheel is rotated as the hall effect sensor is triggered

Condition : Good

¡¡

Problems Status:

1. If the voltage does not change from 0v to 13v but stays at 0v or 1v or 13V

The possible problems

-  There is a fault in the hall effect sensor connector check this again

-  One or more of the hall wires is broken 

-  The Hall effect sensor has failed.

2. If all 3 sensor's wires display in 13 volt  ( no change ) while checking

Condition :  The ground wire is broken ( #2 wire )

¡¡

3. If all 3 sensor's wires display in 0 volt ( no change ) while checking

Condition: The positive wire is  broken ( #1 wire )

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To check for a damaged controller disconnect batterys  set DMV to ohms and the resistance between each motor phase wire ( the other 3 fat wires that go to the motor) and where the controller would normally connect to batt negative should be the same for all three.
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It could allso be the throttle damaged. If you post some pics of throttle I should be able to tell what type and how to test.

If you do open the controller plz post some close up pics

[jeremy]

I think I understand...

The powered controller delivers 5v (or 7 to 9v)  to the sensors (red and black).  As compared to ground, the sensor voltage will vary between 0 and 5v, if working properly, as each magnet passes.  There are 46 rows of magnets, so each sensor should reach 5v 46 times.

I assume then, if the voltage of one of the three sensors remains at 0v as the wheel is rotated, it is disconnected or damaged and must be repaired or replaced.  Likewise, if the voltage of one of the three sensors reaches some voltage between 0 and the max (let's say, it always reaches only 4v), it has moved or is damaged and must be repaired or replaced.  And, lastly, if the voltage of each sensor rises and falls to 5v in a consistent wave-like pattern, then you know the problem is not with the motor.

The only problem is that I don't have a voltmeter on hand.  Could a similar test be conducted using LED's or small light bulbs instead of a voltmeter?

By the way, as it is, I can run the motor, but it makes strong knocking sounds and it doesn't rotate smoothly.  Also, when I apply the throttle, the wheel won't move if it's in certain positions.  I have to bump it forward (or back) from those dead spots to get it to spin.

[myelectricbike]

Sputtering as you describe is typical of a broken or shorted sensor output lead or a damaged sensor. When you had the fall it is possible that a short between a sensor output and a power lead occurred which damaged a sensor but even more likely that a sensor output wire was stressed and broken or that a sensor lead proper coming out of the sensor itself and going to the sensor mounting circuit board was broken since they are brittle to begin with and are weakened by stress from constant tempreature change resulting in metal expansion between the windings and the stator core where the sensors and the circuit board are mounted.

Do not apply more than +5 volts to the sensors power leads as others have advised unless you like your sensors fried! Some are rated as high as 35 volts but unless you know the rating or have replacements don't take the chance. Also do not open your controller! Doing so is absolutely not necessary for this process. In fact I would generally disregard anything anyone has said until you check it out with more than one  other source. Trolls log on to this board all of the time and make statements and give all sorts of incorrect and ill advice just to see how much trouble and damage they can cause.

The magnets turn the sensors on and off in alternating pairs 46 times per rotation. An interuption in the regular pattern indicates what and where the problem is.

Output current from the sensors may be high enough to power an LED but I prefer an interface to let the outputs switch a transitor and the transitors power the leds.  Since +5 volts is the level of TTL you can also automate the process by reading a printer port but that's another story.

[29a]

I think that troll comment was aimed at me
I was posting while you where posting previously "myelectricbike"
I was just trying to help the guy out!

I never advised to apply any power to controller except normal battery power through controller normal leads (sorry if you can't understand simple English)
As I said I don't know this controller (and no one is giving any info on it)or wheather there are connectors between the wheel and controller for access for testing so I advised opening it up for access
I've posted lots of questions here and haven't recieved one full answer so I assumed that this guy would get the same response.
Do you not want to give the specs of the system to stop people knowing what there buying and comparing it to others ?
I would like to purchase a kit but I will not and neither should anyone else untill there are full specifications posted so I know what i'm buying

I agree totaly that people should read everything they can from all sources unfortunately this seems to be the only site that even comments on this system and because you seem to be the authority here and think you know it all, and I've read all the posts here and several of yours seem blatently wrong by my experience and the common opinion on many forums.

[myelectricbike]

Sometimes people intentionally make erroneous comments to solicit an answer. Doing so is a very natural way of learning. Sometimes, however, such comments are inapporpriate because they have an ulterior motive and are injected as a means of interuption.

As for answering a long list of questions and expecting a long list of answers... this is an owner's forum and not a dealership where a salesman is stationed specifically to answer questions for the purpose of making a sale.  If you want answers to such questions then I suggest you establish a relationship with a Golden Motor salesman and explain that your questions are for the purpose of allowing him or her to be able to make a sale.

You are more than welcome to offer an alternate opinion here. If you want it to have merit, however, you must be a Golden Motor owner, or at least a user of a Golden Motor kit.

[29a]

I was a little wound up about that troll comment I appolagise for being obtuse.
 As an owner I would think you would want (as I would) to give the help you didn't have to understand what to expect and what can be done by owners to improve the system for good reliability and max speed /efficency/mods/improvements
I see from

http://goldenmotor.com/SMF/index.php?topic=29.0

there is a lot of variation in the supplied systems which would explain the lack of stat comments.
But shurely couldn't we start a thread on controller mods to help people bring there own controllers at least up to a standard with  optional mods  ?


Does anyone know of a good north american dealer that has this system in stock ?  ( maybe you could get a referal fee )

If anyone does post pics of insides and the specs and part numbers of the controller I will be only too willing to suggest apropriate mods

When I do get this controller the first thing I will do is open it up and put a on-road off-road switch to make this legal in Canada where I am (500W on-road and absolute max amps /volts motor can handle continuous with short max amps turbo, for off-road )

[myelectricbike]

I suggest you start by establishing a relationship with a Golden Motor salesman, i.e., possibly an owner can wear a Golden Motor salesman's hat but not in this forum. The current method of doing this is by sending an email to sales@goldenmotor.com requesting the name, email and address of the Golden Motor dealer nearest to you.

[OneEye]

Is the Canadian power limit a flat 500 watts delivered power? 

My understanding of US law is the power limit is for the continuous rated power, so you could operate above 750 W (perhaps up to 1000 watts?) on a "peak" basis (starting and short hills) and still be compliant with the law.

Not that a mounty or street cop is going to know or care much about the difference unless it is blazoned across the hub (or you go cruising by at 30mph / 45kph)

[OneEye]

Sorry, I failed to include the comment where operating above the limits just to add top end speed is silly and dangerous.  The only practical reason to push the power envelope with mods and wiring changes is to have a reserve to maintain speeds up modest hills.  At some point I think a smart controller (dc brushless controllers are already pretty clever) could deliver higher power at modest speeds, but reduce the power once a certain speed threshold is reached.  Somewhat like a governor in a fleet vehicle.  Too much speed on one of these things will make for nasty falls and unnecessary stresses on spokes rims &c.

[myelectricbike]

Too little speed can result in some pretty nasty falls as well! 

In the US laws that are enforced are usually enforced with absolute determination. For example your birthday is tommorrow and its 10 PM but everybody else is drinking and you have  been drinking since you were 18    (okay 16 but that was only beer) 

The cops get a call to stop a fight and think you still look 18  (okay 16) so the cops ask you for some ID. 

The lawyer asks the judge to give you a break since your watch was in the shop and hey six months probation is plenty. 

Moral: YOU MAY BE DISAPPOINTED IF THE SYSTEM FAILS TO ACCEPT YOUR RATIONAL FOR NOT OBEYING THE LAW. 

[jeremy]

I have some new information.

My motor performs the same whether or not the green lead for one of the hall effect sensors is connected.  I disassembled the motor to inspect that sensor specifically, and there were no visible signs of damage.  I should say that I didn't actually dislodge and remove the sensor to look at it.

By the way, I tried to use a flash light bulb to test for voltage changes on the hall effect sensors as the wheel rotated.  I rigged a 3v flashlight to run this test.  It didn't really work.  No matter what position the wheel was in, each lead produced a similar dim glow.

If it is necessary to replace the hall-effect sensor, how do I choose one with the right...
1.  Supply voltage (voltage)
2.  Current (mA)
3.  Packaging
2.  Operating flux density (guass)
3.  Directionality (uni/bidirectional)

I assume part number DN6848-ND (Fig 2., listed 2nd), available through DigiKey, would work:  http://dkc3.digikey.com/PDF/T072/P2102.pdf

[myelectricbike]

Golden Motor sales suggests Hall Effect sensor type Honeywell SS41.

[jeremy]

Sorry to hear about the storm.

Thanks for the response.  For others, here is a link to the part you named:  http://www.digikey.com/scripts/DkSearch/dksus.dll?PName?Name=480-1999-ND

I plan to buy a multimeter to test this sensor before I actually try to replace it.  That is, unless you think it is obviously the source of my problem based on what I've said here.  In my mind, there is still a possibility that there is an issue with the controller since the hall effect sensor is basically a solid state thing.  What do you think?