IPS122 Unexpected Shutdown Video + Story

[Marcus Matos]

I'm on my second week of ownership of my IPS122 and have enjoyed it greatly. I am commuting to the local rail station on an almost daily basis. I have been in touch with the manufacturer due to a couple of unexpected shutdowns, and while they were very nice in response, the end message was "pay attention to the warning beeps - if it's beeping you need to slow down".

This incident occurred on Saturday, 11/7. I decided to go "practice" around my neighborhood, choosing a route that has a nice mixture of new, paved, smooth sidewalks/bike routes and some challenging areas such as telephone poles right in the middle of the sidewalk, roots pushing up the sidewalk, and intersections without ramps. On this day I had the bonus challenge of gusty winds (up to 20MPH gusts) which definitely added a new dimension to my practicing.

In this portion of the video, I'm on one of the nicer sidewalks fighting a headwind. I noticed a vehicle pacing me to my left, saw they were recording me, so I turned on my camera. I'm unsure of my speed at the time, but I must have been above the max speed threshold as the unicycle suddenly shut off. You can hear the amusement of the strangers that witnessed the event.

Upon review of the video, I can faintly hear the unicycle beeping, so it turns out that I just didn't hear any warning beeps due to the wind. I need to pay more attention in that kind of scenario in the future.

Ironically, it was probably the higher speeds that helped me remain stable in the gusty winds.

https://www.youtube.com/watch?v=uTBX5BrZ43A

 

Note: The purpose of this post was not to dissuade anyone from getting a EUC (IPS or otherwise), but to serve as a warning to those such as myself who crave faster and faster speeds that you need to be very cognizant of the behavior of your EUC and hopefully have good balance / reaction time when something goes wrong.

Despite only owning my IPS122 for 9 days, I'm already looking at upgrading to another model with higher speeds. I live in Dallas, TX which is pretty much just straight, flat roads, and I have several very high quality bike trails around me, so I'm feeling limited by the 12MPH constraint of this model.

[OliverH]

I currently drive an IPS T350. I had the same experience a couple of times. If you're a heavy weight driver you definetly shouldn't go in the area of max speed.

Going uphill it can beep, you wait for cooldown/ battery regeneration and than go ahead and this beast blocks the motor after 200m to throw you to the ground.

Had today a tour with my daughter. We went a nice track and have to drive to the grass to let pedestrians pass by. Suddenly the motor makes his nice overload noise (brrrp). I managed to keep on the IPS.

i'm driving very slow (a bit faster than a normal jogger), so around 12/13 km/h. More is not secure. On a Firewheel F779 I can drive constant on the speed warning (18 km/h) without any problem. So the IPS is not as strong as you often hear. Or the mainboard is limiting the power because of the single battery. This IPS having no parallel batteries with high capacity as Firewheel, Giotway, Kingsong.

[Tilmann]

Hi @Marcus Matos, welcome to the forum! Glad to see neither you nor your wheel was seriously hurt in the incident. 

To me it looks like a classic case of over-stressing available power. You seem to move at about 10mph (pure guesstimate) and it happened very shortly after a change in pavement, which probably included a minor bump. Add headwind, which costs a surprisingly high amount of power to overcome and wooosh, you're on the dark side of the envelope your wheel can handle. Your video stops a tad early: if you could turn the EUC on again, it likely wasn't the BMS cutting the power. If you needed to bring it to a charger to bring it back to life, the BMS was the culprit.

Take care when trading your 122 for a faster model - the problem will persist. But it will likely hit you at a speed beyond any chance to outrun a fall.

[Marcus Matos]

2 hours ago, Tilmann said:

Your video stops a tad early: if you could turn the EUC on again, it likely wasn't the BMS cutting the power. If you needed to bring it to a charger to bring it back to life, the BMS was the culprit.

Hmm. This is new information for me. Yes, I was able to immediately ride it again and did not have any further shutdowns for the rest of the day (another 5-6 miles while taking great care to stay just below tilt-back). This was probably my sixth time dealing with a shutdown and every time I was able to immediately get back on and continue (with a reminder to go slower).

It sounds like the issue is more in the main board thermal/load protection area instead, which is kind of surprising given how they advertise the MOSFETs.

I'm looking at moving to an IPS191, but I guess I will hold off until I become significantly more proficient at treating this one properly.

Thank you for your advice and insight.

[houseofjob]

@Marcus Matos This is not a shutdown, but rather a cutout (machine is still on when you go back for it in the vid); different EUC phenomenon.

At some point, all EUCs can cutout if you are trying to draw more power / current surge than it can handle, sometimes regardless if you are going max speed, as in the case of accelerating up demanding uphills, going against significant winds, stressing the EUC under reduced battery capacity (less current to summon power), or any combination of these factors. It can also happen if you try to accelerate 0 to max instantaneously.

When you pass this point, you overpower the gyro of the EUC and it stops holding up your body weight and the wheel stops rolling, but the EUC is still on.

Cutouts get compounded if you don't have enough cells to draw on (260wh of the IPS is regarded a fairly small battery size here in the forums), or if you are of a heavier weight.

Remember that beeps and tiltback are there to warn you of this fall off point, and that they can trigger even below the designated speed due to reaching this power limit threshold.

[Sweet M]

Marcus,

I've posted a review on my IPS 121/T350+ (which features upgraded speed, stability, and dependability with a higher Wh battery vs the standard IPS 122).  Check it out and feel free to holler with any questions.  I've done extensive ride testing on mine and have developed my own system allowing me to successfully negotiate multiple terrains at a variety of speeds with great safety/dependability (so far anyway....hahaha)!

 

 

[skullforger]

I wonder if there are multiple levels of warning bleeps. All the cutout stories make me very scared and when I hear the warning bleep I immediately slow down. This makes it a very slow EUC though, because my bleep comes on at 16 kph...

Are there multiple levels of warning bleeps? This guy for instance keeps riding with the warning bleep constantly on if you listen carefully. https://www.youtube.com/watch?v=Pvqpfzzlq3Y Is he just lucky to not have a cutout? Or is it because he's maybe a very lightweight person?

Also I find the tiltback kicking in very early, around 13-14kph. All these things make it a slow EUC. It might be due to my heavy weight though (125kg). @Sweet M, could you elaborate on your system to safely negotiate different speeds? Do you know if the old T350 has the same steps of warning as the T350+?

Thanks in advance

[Sweet M]

Re: the old "T350" @skullforger, I have no idea other than the fact that the updated T350+ has a higher speed and besides the higher speed, the updated Plus Series of IPS products also have a more advanced self-balancing system and a more stable motor.  I would assume those facts would make a difference in ride experiences.

Re: my system....................

My warning beeps are as follows per my review in another section:  

I get a slow beep at ~ 22 kph, a rapid beep at ~ 24 kph, and a sustained beep at 27 kph.  I often ride through the slow/rapid beeping but once reaching a sustained beep, I back it down.  My typical long range travel is hanging around the 21-25 kph speed.  

I consider that I have 3 levels of charge:

My rides usually consist of many hills, on/off streets and sidewalks, changing speeds, and carving back and forth as though I'm snow skiing (especially down the hills).

Level 3 (green light constant), Level 2 (green light slow blinking), and Level 1 (green light rapidly blinking).  These simply represent the 33% increments of my T350+ from greatest amount of charge to least. 

If I'm in Levels 2 or 3 I can do pretty much whatever I wanna (of course within reason).  I consider Level 1 though, my "controlled moderation" level.  That's when I'm in that lower 33% charge zone.  In that "controlled moderation" zone, I am careful to not push limits while going up a hill, I don't quickly or aggressively accelerate, nor do I ride beyond the initial warning beeps.  I simply ride at a more controlled pace, stay gradual with my acceleration, and tone down the aggressiveness with maneuvers I perform.  

With this system, I have yet to have a single issue AT ALL (fingers crossed)!  

[Villac]

@Marcus Matos thank you for posting this video. That's a great job running off the cutout; dismounts are much nicer when you keep your feet under you! When I was starting, I learned to sense that split second warning when the EU would lose the ability keep a level pedal and If I had the chance I launched off and ran, rather than drop and roll. Better yet, with time I figured out what the limits of the machine were and stayed back. Still, a cold day or a headwind will change the calculus. It sounds like you will enjoy an EU with a higher top speed, but keep in mind that the factor that allows you to hit and maintain that higher top speed is a higher capacity battery to deliver sustained voltage on uphill and rapid acceleration demands. Have fun!

[Chuts]

Excellent run off!

Is your IPS one of the newer versions that you can unlock to 30kph once you have ridden 100km in total?  Check your documentation... if it can then it should say IPS122+.  In your video it seems that you have reached close to top speed as the beeping usually starts at 17-18kph.  With the IPS122 as with mine it only has the one beep at this higher speed and not one at 12kph like many of the other EUs.

As you are already at top speed and you hit that bump on the path I believe you shot passed the voltage draw limit for that split second causing it to shut down as the BMS is trying to protect the EU.  If the IPS122 is one that you can unlock, once you have unlocked it for 30kph the voltage draw cutoff will be set to a higher rate to compensate for the higher speeds you can go.

Obviously this will happen again if close to 30kph and you hit a bump sending the draw over the limit.  Harder to run off a wheel at 30kph than 20kph.