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Jason McNeil

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Jason McNeil last won the day on March 23

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About Jason McNeil

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  1. Sorry I've been away from the forums for so long, it's been difficult just to keep up managing the email workload. Wanted to address some of the obvious concerns raised here: - Normal charging procedure for this JR-T450 charger, when plugging into an outlet, the LCD display will show the charger's registered voltage, which should be 84.2v +/- .3v. Once charging is complete, it will wind down displaying 0.00v, pressing either the reset button, or disconnecting from the outlet, will reset it. The addition of the LCD display was considered a safety feature, providing the Operator with information about the current state-of-charge & for troubleshooting charger problems. - Partial charging: this charger is programmed to have a termination point of 4.05v @ 80%, or 81v & 4.1v @90% 82v, as @Chriull has pointed out, there's a subsidence effect where the voltage will drop off by about 0.5v @ 5A charging current - 5A Current Safety: The failure is almost certainly not attributable to the current; in the 20s6p configuration, the pack itself is capable of charging at 10A & still be well within the 'normal' charging spec. Recall that when the 16X was first released, KS advertised the max rate of charge of 10A. I have always tried to stay on the side of caution recommending charging not exceed <5-6.5A rapid + standard charger - Charger Abnormalities: whatever had caused this particular charger to go psycho (it had been functioning perfectly normal for 3 weeks), it had exhibited a couple abnormalities—'1 . ' readout, clicking sound, overshooting past the 84v. The lab results will reveal if this is a one-off manufacturing error, or a design fault, where all these chargers are at risk. - Why didn't the BMS prevent the overcharge?: KS sent me a video of their battery pack testing procedure, evidently, they do perform over-charge testing, but this is a couple volts over the 84.2v. It's just a supposition, but if the charger was pumping out an irregular pulsed DC output, perhaps the BMS requires a min_time threshold to shunt the charge input, or the voltage exceeded the BMS MOSFETs max voltage, this may have blown with the gate open, similar to what we see when the in a controller failure where the motor has a lot of resistance when rotated by hand.
  2. Another point I forgot to mention last night: when the first tear-down photos were posted by EcoDrift, I wrote a list of questions about the Nikola, where the selection of these MOSFETs was at the top of this list. MOSFETs: What type of MOSFETs are used in the Nikola, are they HY brand, what model? Why are they not the TO-247 type found in the MSX? Is there now max current regulation in the firmware? If so, what is this value, 100A max? What sets Gotway apart from other Manufacturers, is that their firmware (as of a year ago) does not perform current regulation—this is why their controllers do not contain fuses. I lobbied pretty hard for the TO247 on the Nikola, but the answer I got was that the Wheel had been extensively tested, that fears of going back to bad old days of controller blowouts were unwarranted... You give me too much credit here. Gotway Engineers are no fools, when contrasted to an organization like Ninebot with their vast resources, Gotway have usually been open to reason, & back up their products. This may be true, we need to commission a test rig for stressing the controllers under various loads in test these principles experimentally. I could be wrong, but I suspect that with a drop of efficient thermal compound on the conductive metal surface, will make an dramatic effect on shuttling away heat. In most applications these components are probably not stressed to anywhere to the same degree with as on a Wheel charging up a hill on a hot day, where the standard insulating pad is adequate. Also a special thanks to @Marty Backe & @Phil McLaughlin for their efforts with this investigation.
  3. Yep, this his charred remains of your controller
  4. Tina advised yesterday it's just a couple days delay, we'll see...
  5. Apologies for the late attendance to the party. Since receiving a 2nd board failure (this case was different, it was powered on from a stand still & didn't respond), including Marty's, within two weeks of shipping out the first batch of Nikolas, I've reached out to Linnea on Thursday to try to come up with an action plan to see what options are available to greatly reduce/eliminate the risk of these MOSFET thermal overload events. The evidence from both of these failures has marked similarity in outcome (see below), where this glue may be acting as a thermal barrier, not helped by the absence of thermal paste on the underside of the metal heat transfer surface. One option being explored, is to recall the boards. remove this glue, & apply the thermal paste. To date Gotway have shipped 600 units; they say they have not received reports from other regions of this failure—it's likely more will trickle in in time. Putting out an official recall is not something to be taken lightly; in their defense, they're probably looking for a few other reports, before taking this step. Gotway have a lot of experience with building high power motor vehicles; they had gone through several rough patches, particularly with reliability of earlier generation boards, with the weaker MOSFETS, but at least then they were pretty consistent with applying liberal quantities of thermal paste to this underside. It was baffling to me why they would go back to an inferior TO22x FET package AND now we learn about the lack of thermal paste. From my experience, such oversights are usually not the result of penny-pinching, but execution on the production line, where the factory needs a ruthless eagle-eyed floor manager, to see that every step of assembly is done by the book. The silver-lining to all this, is that an early finding in the production cycle is a necessary facet to a small-scale non-ISO production facility, where the manufacturer's financial pain of having to deal with a crisis, means that they will be imbued with a sense that this situation must never occur again. For all current Nikola owners, please hang in there, we should have an action plan in the next few days. EDIT: To anticipate questions on the 100V Nikolas, they are using the TO247 MOSFET package, the first production of these special edition 1845Wh variants is still underway, there is assurance that in light of this episode, they will getting the thermal paste treatment! 
  6. Apologies for the late attendance to the party. Since receiving a 2nd board failure (this case was different, it was powered on from a stand still & didn't respond), including Marty's, within two weeks of shipping out the first batch of Nikolas, I've reached out to Linnea on Thursday to try to come up with an action plan to see what options are available to greatly reduce/eliminate the risk of these MOSFET thermal overload events. The evidence from both of these failures has marked similarity in outcome (see below), where this glue may be acting as a thermal barrier, not helped by the absence of thermal paste on the underside of the metal heat transfer surface. One option being explored, is to recall the boards. remove this glue, & apply the thermal paste. To date Gotway have shipped 600 units; they say they have not received reports from other regions of this failure—it's likely more will trickle in in time. Putting out an official recall is not something to be taken lightly; in their defense, they're probably looking for a few other reports, before taking this step. Gotway have a lot of experience with building high power motor vehicles; they had gone through several rough patches, particularly with reliability of earlier generation boards, with the weaker MOSFETS, but at least then they were pretty consistent with applying liberal quantities of thermal paste to this underside. It was baffling to me why they would go back to an inferior TO22x FET package AND now we learn about the lack of thermal paste. From my experience, such oversights are usually not the result of penny-pinching, but execution on the production line, where the factory needs a ruthless eagle-eyed floor manager, to see that every step of assembly is done by the book. The silver-lining to all this, is that an early finding in the production cycle is a necessary facet to a small-scale non-ISO production facility, where the manufacturer's financial pain of having to deal with a crisis, means that they will be imbued with a sense that this situation must never occur again. For all current Nikola owners, please hang in there, we should have an action plan in the next few days. EDIT: To anticipate questions on the 100V Nikolas, they are using the TO247 MOSFET package. The first production of these special edition 1845Wh variants is still underway, so there is assurance that in light of this episode, they will getting the thermal paste treatment!
  7. Yeah, we're on the Gotway order queue bandwagon already.
  8. Cool! The YT Review for the Lightning went semi-viral, currently at 270K views, it's giving the Dualtrons a run for their money.
  9. Just received some mock-up photos for the upcoming 16X. The proposed faux carbon-fiber finish looks rather nice, similar to the Z10, I think they're still debating on whether to go with this, or the same rubberized matte black as on the 18XL, 16S, etc... One of the unresolved topics is the color of ornamental side pads. I rather like the dark grey pads to give the Wheel some contrast, from the monotony of the all black, but it is still somewhat in the air. What do you guys think? Put in a vote if you have an opinion.
  10. 98% of the time, the Inmotion Covers do come in the box. In this instance, it was our few remaining V5Fs, the cover stock for this model was depleted, ordered some replacement to be flown in.
  11. Gotway did a similar thing with the Tesla v2 too; even while our order was underway on the production benches, they released the v2. The plan with these Monsters is to negotiate obtaining a supply of these shells to offer as either upgrade replacements or a packaged deal. It doesn't appear that the structure of the body has improved, which was/is the main weakness of this model. Charging at 20A, IMO, is really not a good idea. Will GW be offering a $2m insurance policy if the battery goes up in flames? It's good to see that they've finally adopted the reverse diode protection that we've been using on our special Gotway orders for the past 1+ year.
  12. Preferably a Full-time, there's some flexibility with hours. We're approaching 1000 shipments a month (Wheels, scooters, parts), I'm simply out of capacity to deal with everything.
  13. There is a development update to report; they will be using a new 2200W motor, using a different PWM waveform, to try to match the silent & instant responsiveness of the Gotway controller. Tina says this is not expected to delay the production, currently still on target for next month, however, the demo Wheel is delayed until month's end now.
  14. The clearance between the innershell & the tire is pretty tight. Factors that can influence this are 1) tire pressure, 2) rider weight, 3) position of the foot on the pedal, a stance further out will exert greater inward pressure & flex in the shell body.
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