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[BrianTRice@gmail.com]

Personally, I don't have to graciously characterize Doug's interactions. Prior to receiving the product, he's been publicly and privately acting entitled, insulting, and refused discussion or assistance. I did not expect such aggressive posturing as an entitled expert to precede an uncritical reading and mistake.

As far as I'm concerned, Doug didn't treat what I wrote with respect, and I went out of my way to make this work ahead of time, again pro bono.

A lot of the wiki work took great care to describe general systems theory gleaned both from similar mishaps I've witnessed and learned from others. Does anyone think I didn't make a sacrifice? My DSR was out of commission for a similar procedural error while my 13DS was still in the shop for damage sustained in early spring that derailed my original testing plans. This whole year for me has been a series of delays, headaches, and expenses dealing with this and related projects, and my goal of touring on the DSR was sacrificed to support Ben and related efforts.

I'm hopeful that remote customers take this seriously. What happened here was needless.

[MrDude_1]

I know the Charge Tank also requires the key to be on, so maybe the potential for this failure can't be avoided.

wait. what?
I know this is slightly off topic, but I have to ask this..
When deciding between the Diginow and the chargetank, one of the deciding factors was that the charge tank was designed and programmed into the zero, so you dont have to leave your key in it.  Do you have to leave your key in the bike to charge with it?  Is this just for starting the charge or can you take it back out afterward?
If its exactly like the digicharger, everyone might as well get the digicharger.

[Doug S]

"My mistake was in keying the bike off before starting the Diginow. I read through the installation manual and user guide, but I was still under the impression the Diginow charger would manage the main contactor. I just plain missed the fact that the bike must be keyed on (or the onboard charger started) to close the contactor."

I thought that made it fairly clear that I'm the one that made the mistake. If not, here's a more clearly-worded version: "The user guide and the installation manual both instruct the user to key the bike on, or plug in the onboard charger, before actuating the SC. I read both of those documents, and still managed to do it wrong."

I also mentioned to Brandon early this morning that I really needed to re-read your documents before plugging in for the first time. I'd only read them once, several days before. But even that wasn't quite right. What I REALLY needed to do was have the document open in front of me while I stepped through the process the first time.

When I was working at General Dynamics, we referred to three levels of reliability. We had "idiot-proof", "Bill proof", and finally "clean room proof". Us engineers were the idiots that initially tried to make stuff impossible to blow up. Bill was our boss, who never bothered to check which way he was supposed to plug things in before powering them up; he was the second level of testing. If whatever we were making survived the Bill test, finally, the boys in the clean room would try using it. If they couldn't blow it up, it couldn't be blown up. Hopefully, I'm the Bill in this situation. I do think there are some tweaks possible to the firmware that might help make the product more rugged, and a commercial product needs every ounce of ruggedness it can get. I'm looking forward to discussing some thoughts in that direction with Brandon, not by way of criticizing the excellent work he's done, but hopefully to elevate it even higher. I feel the same way about the excellent work you've done on the documentation. You've made a great knife, but maybe it is possible to capitalize on my stupidity and hone it even sharper. People do stupid things, even us entitled engineers.

There are some abrasive personalities on this forum, and I'm aware I can be one of them. Please don't take any of it personally, at least not from me. You know what us engineers are like; we relentlessly pursue solutions, elegance and capital-T Truth, and our egos can be pretty big because we grew up generally being the smartest kid in the class. It's not intended to hurt or insult anybody, it's just paying too much attention to the technical aspects of a situation, and too little to the social aspects.

[BrianTRice@gmail.com]

I want to make something clear: being abrasive has nothing to do with being an engineer. Imagine your boss claiming that "bosses are just abrasive" - you'd know they were just posturing to avoid figuring out how they're screwing up. Well, that's what I hear when anyone makes that claim about their profession or persona.

The only reason I replied was to disabuse anyone of the notion that you've made some kind of unique sacrifice. Updating the instructions (which is already happening) should not require equipment loss and a personal onsite visit.

Kudos on your hardware work and good luck getting back operational very soon. Next time, try asking questions first or talking through your plans or anything.

Let's try to solve some better problems than this.

[togo]

...  I'm glad by contrast that Ben appreciated the need to interpret the documentation very strictly, and seems to have achieved good results that way....

When I get mine, I am very much going to follow Ben's lead.  High-rate charging is nothing to take lightly.

[DPsSRnSD]

Does anyone think I didn't make a sacrifice?

I wasn't referring to you. Can we keep at least one of these threads PRODUCTIVE and void of this PISSING?

[DPsSRnSD]

I know the Charge Tank also requires the key to be on, so maybe the potential for this failure can't be avoided.

wait. what?
...
  Do you have to leave your key in the bike to charge with it?  Is this just for starting the charge or can you take it back out afterward?

I think there's a link somewhere on this forum with Zero's instructions that I think come with the Charge Tank. I read there about having to energize the bike so that the circuits needed for the Charge Tank would be on. I don't remember what those instructions read about when you can remove the key.

The Zero owner's manual I have reads to have the key on before charging, and remove the key when charging starts.

[MrDude_1]

I know the Charge Tank also requires the key to be on, so maybe the potential for this failure can't be avoided.

wait. what?
...
  Do you have to leave your key in the bike to charge with it?  Is this just for starting the charge or can you take it back out afterward?

I think there's a link somewhere on this forum with Zero's instructions that I think come with the Charge Tank. I read there about having to energize the bike so that the circuits needed for the Charge Tank would be on. I don't remember what those instructions read about when you can remove the key.

The Zero owner's manual I have reads to have the key on before charging, and remove the key when charging starts.

I looked it up in the 2016 manual...  I never knew this... thanks!

[Doug S]

To me, one of the things I struggle with the most in this situation is a lack of information. Perhaps it's just the control freak engineer in me, but for whatever reason, I want to know everything I can about what's going on, and I just don't know a good place to find all the information I think I need.

One of the things I'm just starting to fully understand right now is the concept of the "pre-charge". If you already understand what the pre-charge is all about, or don't want to hear me mansplain it, feel free to click to another post. If you don't know, or want to check your knowledge against mine (and please correct me if I'm wrong about anything!), here's how I understand it.

The main battery has (of course) a very stable, high DC voltage on it. The exact voltage depends on the battery's state of charge, temperature, age, etc. To keep the battery from draining, and to keep things as safe as possible, the main contactor opens up whenever possible to keep the high voltage off of things that don't need to be powered at the moment -- in particular, the motor and its Sevcon driver. That makes things much safer to work on when the bike is keyed off. But those high-voltage circuits have a lot of "bypassing capacitance" (capacitors connected from positive to negative) to stabilize their working voltage, and they hold a charge for a fair while even after the contactor is opened up.

If the bypassing capacitors aren't at the same voltage as the battery, you can't just throw the contactor closed. The capacitors will want to charge virtually instantaneously from the batteries, drawing a REALLY high current spike just as the contactor is at its most vulnerable -- when the contacts aren't quite touching yet. That causes a fat, juicy spark to arc between the contacts, which heats them up so fast it can literally weld them together...and you don't want your contacts welded together. To prevent that, before closing the contactor, a high-power resistor is connected from the battery to the capacitors for a few seconds, charging the capacitors up to the same voltage as the battery with a much more manageable amount of current. The bike's circuitry verifies that the capacitors and battery are at exactly the same voltage before it will close the contactor, so there's no inrush when the contacts are closed, and no spark that can cause grief. That's the "pre-charge", and it's why it takes a couple of seconds before you hear the contactor click after you key on your bike or power up the charger. The SC adds even more capacitance, which it needs for its own operation, so the pre-charge isn't enough to reach full battery voltage, which is why (with the older firmware) you may need to key your bike two or three times before the contactor will close.

This, I'm pretty sure, is why an external charger can't just pull the contactor closed. The external charger can't do a pre-charge to the precise battery voltage because it doesn't KNOW the battery voltage before the contactor is closed, so it can't know when it's safe to close the contactor. That information has to be obtained from the bike's internal circuitry, which has access to the battery's voltage even when the contactor is open. It can verify the capacitors and battery are at the same voltage, and therefore it's safe to close the contactor. The onboard charger apparently also has that information, but I'm guessing the raw battery voltage just isn't exposed to an external charger through the Anderson connector, so it's never safe for the external charger to pull the contactor closed. Keying the bike on, or connecting its onboard charger, pulls the contactor closed safely, after which it's safe for the external charger to maintain the contactor in the closed position.

I think I understand it now (assuming I've figured this all out correctly), and it makes sense why you have to key the bike on to begin charging with an external charger. And it makes sense why not doing so can cause havoc. You're attempting to apply charging current to the battery without the battery being connected.

[MrDude_1]

I think I understand it now (assuming I've figured this all out correctly), and it makes sense why you have to key the bike on to begin charging with an external charger.

I think you have the general idea of it just fine.

If you ever play around with higher voltage (over 50v or so) electric bicycles at all, you'll find you have the same issue swapping packs and plugging in chargers. If I dont precharge my controller before connecting it, it makes a visible pop of light that is visible through the connector plastic, and leaves a nice burn mark on the connecter.
So I have a tiny connector with a resistor in it. Plug it in and a second later the caps are charged close enough I can connect the main battery wires.  The voltage equalization doesnt have to be perfect, it just has to be close enough that theres no huge amp draw to equalize. 
Before I broke down and started putting these equalization connectors on everything, I just had to deal with the loud POP when I did the battery connection... it only took a couple times of me forgetting to look away and getting a blindspot for me to add them. lol

[BrianTRice@gmail.com]

I think I understand it now (assuming I've figured this all out correctly), and it makes sense why you have to key the bike on to begin charging with an external charger.

I think you have the general idea of it just fine.

If you ever play around with higher voltage (over 50v or so) electric bicycles at all, you'll find you have the same issue swapping packs and plugging in chargers. If I dont precharge my controller before connecting it, it makes a visible pop of light that is visible through the connector plastic, and leaves a nice burn mark on the connecter.
So I have a tiny connector with a resistor in it. Plug it in and a second later the caps are charged close enough I can connect the main battery wires.  The voltage equalization doesnt have to be perfect, it just has to be close enough that theres no huge amp draw to equalize. 
Before I broke down and started putting these equalization connectors on everything, I just had to deal with the loud POP when I did the battery connection... it only took a couple times of me forgetting to look away and getting a blindspot for me to add them. lol

This resistor on the Zero is in the BMS, so popping it requires replacing the BMS per OEM rules or doing DIY solid state soldering, very tiny.

[Electric Cowboy]

OK OK boys everything will be just fine. Some people have a tenancy to ignore manuals when they are familiar with the topic, especially at an expert level. I know I have been guilty of this too.

What I REALLY needed to do was have the document open in front of me while I stepped through the process the first time.

That is the point of the documentation, and Brian has done a wonderful job crafting it for that use case too.

While that scenario is so rare to achieve we have never had it happen, and I just tried to do it with Hunter several times, it seems "Bill" (Doug) was combination unlucky and made a mistake at the same time. Unfortunate combination.

Doug also had code which was pre-prod release due to excitement and extreme desire to get the charger ASAP. As of Sunday we had a prod release in the code and after I inspect the situation on Doug's charger, if this is what happened we will rev the code.

All I have to say is good Job everyone for finding what could potentially be the hardest bug to reproduce and Thanks Doug for helping make a better product for everyone else.

Also, @Brian, I think we needn't regale the forum with our sacrifice of time, patience, emotion, stress etc. I mean I don't think most people would be able to even think about what you, Terry, Luke, and I have gone through testing the SC and bug fixing/documenting I mean shit were like CCT, Green Beret. and Delta Force rolled all into one for High Power Charging. The number of times each one of us wanted to give up is unimaginable, but we pushed through it, pushed bikes, and pushed our limits to get this here. Not that we intended to need to put so much into this, but I really am thankful we all stepped up and put in everything we had, quite literally.

 

See you Saturday Doug!

[BrianTRice@gmail.com]

I... look, I'm not bragging. Don't make it harder for me to talk. I've had a rough year and really am not enjoying this situation.

[Doug S]

I'm really trying not to "drama up" the situation. I admit that I did a stupid thing, mostly due to a fair amount of Engineering hubris, and it's going to cost me some time and treasure to get back on the streets. Not the first time it's happened, probably won't be the last, and it's not the most expensive adventure I've ever had, either.

Brandon has graciously offered to come down and help me get rubber turning again, and I appreciate it a lot. He has a lot of knowledge about these bikes that I don't have, and hopefully can help me source the parts I need to get running, and get the SC (and me) operating correctly. Along the way, hopefully this is one more mistake the hardware and/or firmware can be bullet-proofed against, so if anybody else ever makes the mistake I made, it won't destroy anything.

It's not that big of a deal, in my mind. All part of product development. If you want to make an omelet, you gotta crack a few eggs.

[Killroy]

I find it surprising that you need to turn the motorcycle "on" to use the charge tank, when you don't need to do that for level 1 charging.