Power issues with Voilamart kit

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
Hi everyone.
I'm new to the site but hope someone can help.
Back in in the first lockdown, I took the plunge and purchased a basic e-bike kit from Voilamart. It was a 250/500W rear hub mounted motor, thumb throttle with 3 led battery indicator, pedal assist sensor and controller. It worked fine, but I found that when using pedal assist (even just rotating the pedals), the motor just gave max power and propelled me along to max speed. I wanted to be able to vary the power during pedal assist so purchased from Voilamart a SW900 LCD display, different controller and thumb throttle without the 3 battery LED’s.
The problem is, despite what power setting I select, 1 to 5, I still seem to get max power to the motor during pedal assist. The motor can be controlled on the thumb throttle to give varying degrees of power, but the pedal assist, no chance.
I have raised this with Voilamart without success, changing all the settings they suggested but to no avail.
My current set up and settings are as shown with comments about what settings I have tried to adjust:-
  1. Voilamart rear wheel hub motor, serial Number – ZC620030170
  2. DC MOTO CONTROLLER By LITHIUM BATTERY, Voltage:DC36/48V Off road:22+/-1A(750W), IN Recad(With speed limitor): 15+/-1A(250W), Speed Set: 1.1-4.2VDUAL MODE BOOSTER 1:1, 20200305YF LCDSM
  3. 8 Magnet pedal assist sensor
  4. Thumb throttle
  5. SW900 LCD display
  6. 36v 10Ah battery
P1 = 1 Darkest LCD Display backlight.
P2 = 1 Set to indicate miles.
P3 = 36 Voltage of my battery.
P4 = 5 Sleep time switch off 5 minutes.
P5 = 1 Power mode giving 5 power settings. I have also tried setting P5 = 0 (3 power levels) and P5 = 2 (9 power levels) but still cannot get the power levels to change.
P6 = 26 Wheel size 26 inches.
P7 = 46 Tried adjusting but just alters the displayed speed.
P8 = 100 Speed limit set to 100kmh.
P9 = 0 Immediate access to throttle.
P10 = 2 2 should mean both pedal assist and thumb throttle operate, but I have tried P10 = 0 (which should be pedal assist only) and P10 = 1 (which should be thumb throttle only) and still both pedal assist and throttle operate regardless of setting.
P11 = 24 PAS sensitivity set to high.
P12 = 5 PAS start strength set to high.
P13 = 8 Set to 8 because I have 8 magnet PAS sensor.
P14 = 12 Current limit set to 12A.
P15 = 30.5 Tried adjusting up and down with no effect on power delivery.
P16 = 6 Unable to change this setting.

Any help with this issue will be greatly appreciated.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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Basildon
You should have asked when you first noticed the shortcomings of your original installation. You have the wrong type of controller. What you need is a KT controller. They give true power control, while as yours uses speed control, so you get full power in all levels, each with a different speed limit.

Get the LCD3 with it. The rest of the stuff is up to you:


This one is sine wave, a bit bigger and a bit more powerful. You can turn down the current to 22A in the settings if 25A is too much for your battery.

 
Last edited:

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
Hi vfr400
Thanks for the quick response.
All kit was supplied through Voilamart so I assumed it would all be correct and work. My mistake!

For the KT controller, would be any of the ones on ebay, such as this one for instance?
New E‑Bike Conversion 6Tube 36/48V KT‑17A All Normal Heads Rectangula Controller | eBay

Will my SW900 work with the KT controller?

Whats worse is I already have a successful CSC kit fitted to another bike which works correctly. I never considered swapping controllers to see if would work on the Voilamart for fear of damaging the equipment. I was also unsure about motor compatibility as the Voilamart motor looks very different to my CSC one.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
Hi vfr400
Thanks for the quick response.
All kit was supplied through Voilamart so I assumed it would all be correct and work. My mistake!

For the KT controller, would be any of the ones on ebay, such as this one for instance?
New E‑Bike Conversion 6Tube 36/48V KT‑17A All Normal Heads Rectangula Controller | eBay

Will my SW900 work with the KT controller?

Whats worse is I already have a successful CSC kit fitted to another bike which works correctly. I never considered swapping controllers to see if would work on the Voilamart for fear of damaging the equipment. I was also unsure about motor compatibility as the Voilamart motor looks very different to my CSC one.
You should always buy a KT controller with a matching LCD because there can be some software differences, which can cause surprises after you install.

I'm guessing that your motor is a direct drive one. Please confirm. They're very power hungry, so a 17A controller would be running at its maximum for a lot of the time, which would probably overheat it. You need a 9 or 12 mosfet one, with the 12 mosfet one obviously being a bit more robust. Most of the 9 mosfet ones are square wave, so not quite as smoothe. some are labelled as sine wave, but I have some doubts after seeing a technical explanation about why it's not possible to have sine wave with 9 mosfets.

I can understand why you bought that controller. It works OK, but it's not designed to give you the feature that you want. Generally, the more powerful your motor, the more important it becomes to get a controller with a decent PAS function. In the past, I've come across some truly dreadful systems, like the one that gave power in proportion to pedal speed. It sounds sort of logical, but in practice, it's diabolical.

While I'm at it, crappy controllers is one of the reasons why people try a hub-motored bike, hate it and migrate to a torque sensor crank-drive bike. Thankfully, most established brands have wised up, but there are still some of the bad controllers around, even on new bikes, with long cut in and cut out delays as well as very poor power algorithms.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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Nothing wrong with the Voilamart kit/controller if you like that sort of rough power delivery, they do what they intend to do which is to give a cheap powerful product with little control by the end user. One has to pay a bit more money for better sophisticated controller kits.
 

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
All good information, thanks.

I've ordered a KT controller and LCD3 to go with it which should make the Voilamart setup more useable.

One more question. Does it matter the number of magnets on the pedal assist sensor disk for the KT controller? For example, on my current Voilamart setup I have a 12 magnet disc, but on my CSC setup (which already uses a KT and LCD3) I have 8 magnets?
 

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
Hi all.

The KT controller and LCD3 arrived today. I got them on the bike but have a problem. The display works, the thumb throttle works but the PAS doesn't work at all regardless of power setting 1-5.

I have gone through the many settings and even compared them to my other bike setup which has KT controller, half throttle, 12 magnet PAS and CSC rear hub motor. The only difference now on the bike I am struggling with is the PAS sensor has 8 magnets and a Voilamart rear hub motor.

My settings at the moment are

1. - 72
2. - 26
3. - mph

P1. - 100
P2. - 1
P3. - 1
P4. - 0
P5. - 12

C1. - 7
C2. - 0
C3. - 8
C4. - 0
C5. - 10
C6. - 3
C7. - 0
C8. - 0
C9. - 0
C10. - n
C11. - 0
C12. - 4
C13. - 0
C14. - 2

Hopefully someone will see something obvious in the settings and suggest something else. In the meantime, I am going to try and fit a 12 magnet sensor to see if that works. If not, I may just bite the bullet and ditch the Voilamart motor and put in a CSC one in its place.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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Basildon
What colour wires do you have on each side of the connector, and which is connected to which?
 

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
On the PAS there are red, white and black and from the controller, yellow, black and brown. They are connected as follows;
black to yellow
white to black
red to brown

I have also noticed on the six pin connector that there are only five wires from the Voilamart motor, red, black, blue, green and yellow. On my working bike, there is a sixth white wire which the Voilmart doesn't have.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
That's why it doesn't work. it should be black to black, red to brown and yellow to white.

The white wire is for a speed sensor integrated into the motor. if you don't have the speed sensor in your motor, you need to connect an external one if you want to see your speed on the LCD and ypur system not to go to sleep every 5 minutes or whatever it's set to.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,995
8,175
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Once the PAS wire sequence is correct change C1 to 0 or 1 as well. C7 shouldn't work with any basic 5 - 12 pole magnet.
 

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
Morning all.

I changed the wiring as vfr400 suggested, set C1 to 0 as Neilh suggested, and now the PAS works. Thanks you both for your input and getting things sorted for me.

One peculiar thing though is the speed now seems to be working too. Odd without the white wire I mentioned earlier, but if I think about it, the speed worked on the previous controller supplied by Voilamart, so not really sure what to make of that.

Anyway, off out now to test it out propoerly and I'll let you know how it performs.......
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,995
8,175
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The C1 PAS parameters works depending on the sensor type used, the 5 -10 pole discs with supplied sensors are the most basic simple ones and C1/0 - C1/2 will work with them.
 

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
Just completed an 8 mile ride and a few issues have surfaced.

1. The speed reading, although working, is reading faster than actual.
2. As I got to towards two bars on the battery indicator, the PAS was starting to become erratic, kicking in and cutting out, almost like there wasn't enough in the battery to work the motor. It did seem to use the battery more rapid than with the previous controller with the new KT. The battery is a 36v 10AH with about 200 miles use and is less than a year old so I was hoping it wasn't a cell breakdown. To test, I put the same battery on another bile and it was working fine.

I am sure that these issues are more to do with the settings, so if anyone can give some more insight, it would be really appreciated.
 

hurtlocker66

Finding my (electric) wheels
Feb 5, 2021
12
2
KT36/48ZWSRTD-SJT02L2.
Max Current - 20 +/- 1A
Rated Voltage - DC36V/48V
Speed Set 1-4. 2V
Rated Current - 10A
Brake Input: Low Level
Low Voltage Protection - DC30/40 +/- 0.5V
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,995
8,175
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1. P1 needs adjusting, the figure is set to high. First check wheel size is correct.
If the hub is a DD hub then P1/46 will be fairly close to fine tune the speed go up or down by 1 numeral. < to lower the reading & > to raise the reading.

2. If P1 is far out then it can I believe affect the fluidity of motor speed/loss of sync pick up is what I called it causing nano second motor cut out. A few years ag I posted about this and had a similar experience adjusting P1 cleared it up for me.
It is nothing to do with the battery but P1 setting.

Make sure the motor cable Julet connection is properly home and pushed hard up to the raised/embossed mark.
Which type of controller connections are used Julet or older style.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
Have a look at the watts displayed in the LCD. You should be seeing around 100w in level 1.

What sort of PAS level were you using?